- Email: [email protected]
Novel biomarkers in malignant melanoma
Clinica Chimica Acta 367 (2006) 28 – 35 www.elsevier.com/locate/clinchim
Review
Novel biomarkers in malignant melanoma Anja K. Bosserhoff * Institute of Pathology, University of Regensburg, Franz-Josef-Strauss-Allee 11, D-93053 Regensburg, Germany Received 21 July 2005; received in revised form 25 October 2005; accepted 26 October 2005 Available online 9 February 2006
Abstract Cutaneous malignant melanoma remains the leading cause of skin cancer death in industrialized countries. Melanoma progression is well defined in its clinical and histopathological aspects (Breslow’s index, tumour size, ulceration, or vascular invasion), which also give hints to prognosis of the patient. Use of molecular markers should therefore give additional information which cannot be determined by routine histopathology. Markers showing only a correlation to Clark level or tumour size are not useful. Several molecules influencing invasiveness and metastatic dissemination of melanoma have been identified. Expression of these molecules has been studied in primary melanoma and correlated with prognosis. Moreover, several tumour suppressors and oncogenes have been shown to be involved in melanoma pathogenesis, including CDKN2A, PTEN, TP53, RAS and MYC, but have not been related to melanoma subtypes or validated as prognostic markers. In the past, in melanoma, an increase in the number of positive tumour cells for Ki67 (detected by Mib1), cyclin A, cyclin D, MMP-2, integrins beta1 and beta3 or osteonectin were considered as factors of poor prognosis as well as the decrease in p16, p27, and Melan A. However, only a small subset of these proteins has a prognostic value independent of tumour thickness. The recent development of high-throughput technologies analyzing global molecular profiles of cancer is bringing up previously unknown candidate genes involved in melanoma, such as Wnt-5A and B-raf. Here, recently published data related to new genes involved in melanoma pathogenesis, which may represent important biomarkers for the identification of genetic profiles or indication of progression of melanoma, are reviewed. D 2006 Elsevier B.V. All rights reserved. Keywords: Malignant melanoma; Biomarker; Prognosis; Candidate genes; Screening; Melanoma pathogenesis
Contents 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.
Introduction . . . . . . . . . . . . . . . . . . Phosphorylated AKT . . . . . . . . . . . . . . Angiogenic factors . . . . . . . . . . . . . . . Apaf-1 (apoptotic protease-activating factor-1). Bcl-2 . . . . . . . . . . . . . . . . . . . . . . h-Catenin. . . . . . . . . . . . . . . . . . . . Cell – cell and cell – matrix-adhesion molecules CXCR4. . . . . . . . . . . . . . . . . . . . . Cyclooxygenase-2 (COX-2) . . . . . . . . . . Ets-1 . . . . . . . . . . . . . . . . . . . . . . HIF (hypoxia-inducible factor) . . . . . . . . . MITF (microphthalmia associated factor) . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
* Tel.: +49 941 944 6705; fax: +49 941 944 6602. E-mail address: [email protected]. 0009-8981/$ - see front matter D 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.cca.2005.10.029
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
29 29 30 30 30 30 31 31 31 31 32 32
A.K. Bosserhoff / Clinica Chimica Acta 367 (2006) 28 – 35
13. MTAP (methylthioadenosine phosphorylase) . . . 14. Pleiotrophin . . . . . . . . . . . . . . . . . . . 15. PLK-1 (polo-like kinase 1) . . . . . . . . . . . . 16. PUMA (p53 upregulated modulator of apoptosis) 17. SOCS (suppressors of cytokine signalling). . . . 18. Wnts . . . . . . . . . . . . . . . . . . . . . . . 19. Summary . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
1. Introduction Cutaneous malignant melanoma remains the leading cause of skin cancer death in industrialized countries. Melanoma progression is well defined in its clinical and histopathological aspects (Breslow’s index, tumour size, ulceration, or vascular invasion), which also give hints to prognosis of the patient. Use of molecular markers should therefore give additional information which can not be determined by routine histopathology. Markers showing only a correlation to Clark level or tumour size are not useful. Several molecules influencing invasiveness and metastatic dissemination of melanoma have been identified. Expression of these molecules has been studied in primary melanoma and correlated with prognosis. Moreover, several tumour suppressors and oncogenes have been shown to be involved in melanoma pathogenesis, including CDKN2A, PTEN, TP53, RAS and MYC, but have not been related to melanoma subtypes or validated as prognostic markers. In the past in melanoma an increase in the number of positive tumour cells for Ki67 (detected by Mib1), cyclin A, cyclin D, MMP-2, integrins beta1 and beta3 or osteonectin were considered as factors of poor prognosis as well as the decrease in p16, p27, and Melan A [1– 7]. However, only a
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
29
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
32 32 32 33 33 33 33 34
small subset of these proteins has a prognostic value independent of tumour thickness. The recent development of high-throughput technologies analyzing global molecular profiles of cancer is bringing up previously unknown candidate genes involved in melanoma, such as Wnt-5A and B-raf [8,9]. Here, recently published data related to new genes involved in melanoma pathogenesis, which may represent important biomarkers for the identification of genetic profiles or indication of progression of melanoma are reviewed (genes are presented in alphabetical order). The main information is summarized in Table 1.
2. Phosphorylated AKT AKT (or protein kinase B (PKB)) is a serine/threonine kinase that leads to stimulation of cell cycle progression, cell proliferation, and inhibition of apoptosis [10]. Strong pAKT expression was observed in one study in the biopsies of 17% of normal naevi, 43% of dysplastic naevi, 49% of primary melanoma, and 77% of melanoma metastases, respectively [11]. Significant differences for p-AKT staining pattern were observed between normal naevi and primary melanomas and between primary melanomas and melanoma
Table 1 Overview on markers described Marker p-AKT Ephrin A1 Apaf-1 Bcl-2 h-Catenin CEACAM1 P-cadherin CXCR4 Cox-2 Ets-1 HIF MITF MTAP Pleiotrophin PLK-1 PUMA SOCS Wnts
Correlation with tumour thickness
Correlation with pathological stages
Correlation with survival
Independent prognostic marker
–
–
This table summarizes the data presented in the review (: was shown, – : could not be determined, empty field: not analysed).
30
A.K. Bosserhoff / Clinica Chimica Acta 367 (2006) 28 – 35
metastases, respectively, showing that activity of AKT increases dramatically with melanoma invasion and progression. Furthermore, Kaplan – Meier survival curves showed that strong AKT activity is inversely correlated with both overall and disease-specific 5-year survival of patients with primary melanoma. Multivariate Cox regression analysis revealed that p-AKT is an independent prognostic factor in low-risk melanomas. Therefore, pAKT is considered as an independent prognostic marker that may help to identify those patients with ‘‘so-called’’ low-risk melanomas who are actually at increased risk of death.
3. Angiogenic factors The expression of several angiogenic factors and receptors was examined in a series of vertical growth phase cutaneous melanomas using high-throughput tissue microarray technology and immunohistochemistry in a study by Straume and Akslen [12]. Expression of basic fibroblast growth factor (bFGF) was significantly associated with increased microvessel density in melanomas. Strong expression of FLT-4, ephrin-A1, and EphA2 (receptor for ephrin-A1) on tumour cell was associated with increased melanoma thickness, and ephrin-A1 staining was related to decreased survival. Expression of EphA2 in tumour cells was associated with increased tumour cell proliferation (Ki67 positivity), indicating possible autocrine growth stimulation. The use of Ephrin-A1 and EphA2 as biomarkers was also supported by another study of Easty et al. [13].
4. Apaf-1 (apoptotic protease-activating factor-1) The exact mechanism for failure in the apoptotic pathway in melanoma cells is unclear. p53, the most frequently mutated tumour suppressor gene in human cancers, is a key apoptosis inducer. However, p53 mutations are only found in 15– 20% of melanoma biopsies [14]. Apoptotic proteaseactivating factor-1 (Apaf-1) is a cell death effector that acts with cytochrom C and caspase-9 to mediate apoptosis [15,16]. Recently, it was shown that metastatic melanomas often lose Apaf-1 and are concomitantly resistant to apoptosis [17]. A significant decrease in Apaf-1 expression was observed when comparing naevi and melanomas. Moreover, primary melanomas with greater tumour thickness showed lesser expression of Apaf-1 and Apaf-1 expression in lesions of metastatic melanomas was undetectable. These data demonstrated that there is an inverse correlation between Apaf-1 expression and pathologic stage of melanoma [18]. Additional immunohistochemical studies gained equal results showing that Apaf-1 expression is significantly reduced in melanoma cells compared with normal naevi. An association of Apaf-1 and tumour thickness was discussed controversially [19,20].
5. Bcl-2 The Bcl-2 oncogene belongs to a new category of oncogenes that influence tissue homeostasis regulating cell death. The gene encodes for a protein that preserves cells from death by apoptosis, allowing them to survive in G0 phase even in the absence of essential growth factors [21]. The anti-apoptotic protein Bcl-2 is supposed to influence the treatment responsiveness of different malignancies. Diverse results found in the literature may be due to use of small cohorts or variability in staining technique [22]. The presence of Bcl-2 immunoreactivity was associated with a significantly reduced proliferation and a longer disease-free survival. In contrast, the lack of Bcl-2 expression was related to a higher response rate to therapy. The results support the role of Bcl-2 in the regulation of cell proliferation and suggest that an increase of metastatic potential and progression of malignant melanoma is associated with a loss of Bcl-2 expression [23]. These results were supported by a study of Divito et al. [24]. Here, high Bcl-2 expression was associated with better outcome in the entire cohort and among metastatic specimens. Expression was higher in primary than in metastatic specimens. 6. B-Catenin h-Catenin plays a crucial role in the function of cell adhesion molecules and also participates in growth regulatory signalling pathways that may be involved in malignant transformation [25,26]. h-Catenin expression was examined by immunochemical staining in a study by Kageshita et al. [4]. They found h-catenin expression in 96% of melanocytic naevi, in 94% and 65%, respectively, of radial and vertical growth phase of primary melanomas, and in 38% of metastatic melanomas. Absent or weak expression of hcatenin in primary melanomas was associated with several markers of disease progression, including tumour thickness and presence of lymph node metastases. Their results suggest that loss or downregulation of h-catenin expression in melanoma cells plays a significant role in progression of the disease. In another study antibodies specific to phosphorylated h-catenin were used [27]. Evaluation of phospho-h-catenin staining showed that cytoplasmic/nuclear staining was more common in primary lesions, whereas nuclear phospho-h-catenin was found more often in metastatic lesions. High levels of nuclear phospho-h-catenin are associated with significantly worse overall survival. These results suggest that phospho-specific antibodies to h-catenin identify a unique subset of cases with poor clinical outcome and that monitoring of phospho-h-catenin expression may be useful for assessing prognosis in malignant melanoma.
A.K. Bosserhoff / Clinica Chimica Acta 367 (2006) 28 – 35
31
7. Cell – cell and cell –matrix-adhesion molecules
8. CXCR4
Malignant melanoma usually progresses from the intraepidermal microenvironment through a distinct radial growth phase, in which malignant potential cannot always be accurately evaluated, to invasion of the dermis (vertical growth phase) and metastasis. During these stages malignant cells interact with each other and with the extracellular matrix. The expression pattern of integrin-type cell adhesion receptors is often changed during malignant transformation [28]. Next to several integrins, cadherins, MUC18, ICAM-1 and NCAM are known to be deregulated [29]. Haritopoulos et al. reported that ICAM-1 immunopositivity status was significantly more frequent among malignant melanomas of the nodular type, and was associated with the vertical growth phase, Breslow thickness of > 0.77 mm, and with evident lymphocytic infiltration. Integrin beta3 immunopositivity showed similar results in certain respects; it was more frequently detected in superficial spreading melanomas in which vertical growth had developed and in cases with regression [6,30]. The cell adhesion molecule CEACAM1 is involved in intercellular adhesion and subsequent signal transduction events in a number of epithelia. CEACAM1 downregulation has been demonstrated in colorectal and prostate carcinomas [31,32]. Interestingly, expression in malignant melanoma is associated with metastasis [33,34]. Often, the strongest CEACAM1 expression was observed at the invading front. In addition, CEACAM1 expression was preserved in the metastatic lesions. Kaplan –Meier analysis revealed a highly significant association between CEACAM1 expression and metastasis. Multivariate Cox regression analysis, including CEACAM1 expression status adjusted for tumour thickness, presence of ulceration, and mitotic rate, confirmed that CEACAM1 is an independent factor for the risk of metastasis and demonstrated that the predictive value of CEACAM1 expression is superior to that of tumour thickness. Therefore, expression of the cell adhesion molecule CEACAM1 in primary tumours in melanoma patients is associated with the subsequent development of metastatic disease. It was shown that membraneous P-cadherin expression is reduced or lost in malignant melanoma [35,36]. In a study of Pacifico et al. loss of P-cadherin expression was found to be significantly correlated with outcome [37]. A so far unpublished study using melanoma tissue microarrays revealed that, in general, P-cadherin expression was significantly reduced in malignant melanomas and melanoma metastases compared to benign naevi (Bauer et al., unpublished results). Additionally, loss of membranous Pcadherin was associated with Clark level and tumour thickness. Further, low P-cadherin expression was associated with tumour recurrence suggesting P-cadherin expression to be a predictive marker of progression in melanoma patients.
CXCR4 and its unique ligand, the CXCL12 chemokine, have been recently implicated in cancer metastasis [38,39]. Evidence about the role of CXCR4/CXCL12 axis has been reported in several cancers including melanoma. CXCR4 expression was reported to have a prognostic value in malignant melanoma [40,41]. The CXCR4 expression on tumour cells was correlated with an unfavorable prognosis. The expression of CXCR4 by melanoma cells in primary lesions was significantly associated with the presence of ulceration, increased tumour thickness, a greater risk of developing regional and distant metastases and a higher mortality rate. In multivariate analysis CXCR4 expression emerged as independent prognostic factors. Therefore, CXCR4 expression could be an independent and powerful prognostic marker in primary cutaneous malignant melanomas.
9. Cyclooxygenase-2 (COX-2) COX-2 is an inducible enzyme involved in production of prostaglandins in inflammatory processes [42]. There are now several lines of evidence indicating that increased expression of COX-2 plays a functional role in the development and progression of malignant cancers [43]. Denkert et al. investigated expression of COX-2 in cases of primary skin melanoma and benign naevi and detected expression in almost all melanoma but benign naevi as well as normal epithelium were negative in all cases [44]. In addition, Goulet et al. examined lesions through out the development of melanoma and metastatic disease (dysplastic naevi, melanoma in situ, stage II melanoma, stage III, stage IV, stage V, melanoma metastasis lymph nodes and metastasis to other sites) [45]. No COX-2 staining was detected in naevi. However, in contrast to the study of Denkert et al., COX-2 expression was not found in primary skin melanoma cells and in all vertical and radial growth phase cases. In contrast, all lymph node metastasis and metastatic cancer cells expressed high levels of COX-2. Collectively, these data suggest that COX-2 may play a functional role in metastases of melanoma, and treatment with COX-2 inhibitors may be efficacious for malignant melanoma.
10. Ets-1 Ets-1 oncoprotein is a transcription factor known to regulate the expression of numerous genes important in extracellular matrix remodeling and angiogenesis [46 – 48]. Ets-1 has been associated with tumour progression in various carcinomas, but its expression in malignant melanoma was only recently described [49]. Immunohistochemical studies revealed lower expression of Ets-1 in primary melanomas than in common naevi and further, in metastatic melanomas than in primary melanomas [50,51]. No association between
32
A.K. Bosserhoff / Clinica Chimica Acta 367 (2006) 28 – 35
Ets-1 expression and disease-specific survival or time to treatment failure, respectively, could be shown. In another study, however, increased staining in metastases compared to primary tumours, and in primary tumours compared to naevi was found. There was a trend toward more intense staining with melanoma progression. A statistically significant difference in the mean labeling intensity of Ets-1 was seen between invasive melanoma and benign melanocytic naevi. Therefore, Ets-1 expression cannot be used to differentiate between benign and malignant melanocytic lesions and it has no definite association with clinical outcome. Its role in tumour progression in some cases of malignant melanoma cannot be entirely excluded where Ets-1 expression may be an important pathogenic mechanism [49].
gression of melanocytic tumours as the amount of MTAP protein staining decreased from benign melanocytic naevi to metastatic melanomas [65]. In a multiple tissue array the prognostic value of MTAP expression was analyzed (own unpublished data). MTAP expression was significantly reduced in malignant melanomas and melanoma metastases compared to benign naevi. In primary melanomas, only a low Ki-67 labeling index < 5% was associated with MTAP protein expression. In an explorative subgroup analysis, considering 26 patients with MTAP positive melanomas and recorded tumour recurrence, patients with interferon therapy had a significant benefit compared to patients without interferon treatment. Therefore, MTAP protein expression could be a predictive marker of therapy resistance in melanoma patients with disease progression and treated with interferon.
11. HIF (hypoxia-inducible factor) Hypoxia is a key regulatory factor in tumour growth, activating angiogenesis, glycolysis and cell migration. It is readily recognized by the intracellular accumulation of hypoxia-inducible factor 1alpha (HIF1alpha) and HIF2alpha [52 –55]. HIF1alpha and HIF2alpha accumulation in malignant melanomas was directly correlated with VEGF expression [56]. High HIF2alpha expression in tumours was associated with poorer prognosis in both univariate and multivariate analyses. Therefore, HIF2alpha was suggested to be an important prognostic factor in melanoma.
12. MITF (microphthalmia associated factor) The transcription factor (MITF) is required for the formation of normal melanocytes during embryonic development and for the expression of pigment cell-specific markers, which are the downstream transcriptional targets of MITF [57 – 59]. Further, MITF seems to be crucial for the survival of malignant melanocytes. Recently, MITF was suggested as a marker of malignant melanoma [60]. Melanocyte-specific isoform of MITF appears to be a unique molecule in the differential diagnosis of melanocytic tumours. Loss of MITF expression correlated inversely with overall survival and disease-free survival suggesting that MITF may be a new molecular prognostic marker in patients with melanoma [61]. One study presented MITF as a sensitive and specific marker for malignant melanoma and hypothesized MITF to be superior to the current standard melanocytic markers, S-100 protein and HMB-45 antigen [62]. However, other studies could not verify the usefulness of MITF as biomarker [63,64].
13. MTAP (methylthioadenosine phosphorylase) Recent studies demonstrated a significant inverse association between MTAP protein expression and pro-
14. Pleiotrophin GENE expression profiling of melanoma and naevi tissue has demonstrated that pleiotrophin (PTN) is significantly overexpressed in human melanomas [66]. Pleiotrophin is also named heparin-binding neurite outgrowth-promoting factor being a member of a highly conserved human gene family of proteins. It exhibits neurite outgrowth-promoting activity and may play a role in nervous tissue development and/or maintenance [67,68]. By immunohistochemistry melanocytic naevi were shown to be consistently negative, whereas the great majority of metastatic melanomas were positive [69]. Within the primary melanomas, PTN immunoreactivity was associated with metastasis and decreased melanoma-related survival. As PTN expression is associated with metastatic potential, PTN may be a prognostic factor for melanomas.
15. PLK-1 (polo-like kinase 1) Polo-like kinase 1 (PLK-1) is involved in regulating mitotic spindle function. Microinjection of PLK mRNA induced mitosis in quiescent cells [70]. Constitutive expression of PLK caused cells to proliferate in low serum media and cells transformed with PLK grew in soft agar and produced tumours in nude mice [71]. Therefore, PLK may be involved in the promotion or progression of cancers. In a recent study Kneisel et al. examined thin malignant melanomas with immunohistochemical techniques using monoclonal antibodies directed against PLK1 [72]. Malignant melanomas with metastases expressed PLK1 at markedly elevated levels compared to melanomas without metastases. These preliminary data suggest that PLK1 expression in thin melanomas may be a reliable marker to identify patients at high risk for metastases.
A.K. Bosserhoff / Clinica Chimica Acta 367 (2006) 28 – 35
16. PUMA (p53 upregulated modulator of apoptosis) PUMA (p53 upregulated modulator of apoptosis, or Bcl2-binding component 3; BBC3) was shown to bind to Bcl-2, localize to the mitochondria to induce cytochrome C release, and activate the rapid induction of programmed cell death [14,73,74]. In a study by Karst et al. PUMA expression was analyzed in primary melanomas, metastatic melanomas, and dysplastic naevi [75]. PUMA expression was significantly weaker in primary melanomas compared to dysplastic naevi and is further reduced in metastatic melanomas compared to primary tumours. Weak PUMA expression in melanoma correlated with poorer overall and disease-specific 5-year survival of melanoma patients showing PUMA expression in tumour tissue as an independent predictor of both overall and disease-specific 5-year survival. Additionally, it was shown that exogenous PUMA expression in human melanoma cell lines (both wild type and mutant p53) results in significant apoptotic cell death.
17. SOCS (suppressors of cytokine signalling) Cytokines induce a variety of biologic responses by binding to specific cell surface receptors and activating cytoplasmic signal transduction pathways. Cytokine resistance is a well-established feature of melanoma cell progression and represents also a major obstacle in immunotherapy of patients with metastatic melanoma. SOCS-1, an established negative regulator of interleukin6 (IL-6) and interferon (IFN) signalling, could play a crucial role in this process [76 – 78]. Recently, Li et al. analyzed whether SOCS play a role in cytokine resistance and tumour progression of melanoma [79]. Aberrant SOCS-1 protein expression in melanoma cells in vitro and in situ was shown by immunohistochemical analysis. SOCS-1 immunoreactivity was closely related to tumour invasion (Clark level), tumour thickness, and stage of the disease. In contrast, melanocytes in normal skin or melanocytic naevi lacked SOCS-1 protein expression. SOCS-1 seems to be a progression marker of human melanoma and may downregulate biological responses by endogenous and/or therapeutically administered cytokines.
18. Wnts Secreted Wnt ligands are key proteins regulating cell – cell interactions and cell growth and differentiation. These proteins, along with other components of the Wnt signaling pathway, are involved in the malignant transformation of various human cancers, including malignant melanoma [8]. As development of antibodies only started a first study was performed by in situ hybridization.
33
Pham et al. analysed expression of several members of the Wnt ligand family and correlated expression with histological characteristics [80]. All naevi tested strongly expressed Wnt2, Wnt5a, Wnt7b, and Wnt10b. Melanomas characterized by small, uniform cells expressed each of the Wnts in a pattern similar to that seen for benign naevi. In contrast, melanomas characterized by large, pleomorphic cells expressed Wnt10b but did not express Wnt2 and had low levels of expression of Wnt5a. Expression of Wnt7b was variable in these melanomas. The expression pattern of Wnt ligands in malignant melanoma correlates with histopathological features and may provide a basis for the molecular classification of this disease.
19. Summary Melanoma is a complex multigenic disease which is determined by several parallel and stepwise progressive pathways affecting growth control, differentiation, cell adhesion, and survival. Melanoma and human cancers in general undergo a continuous development from benign to malignant states, as most thoroughly documented in the multi-step naevi-to-melanoma transition [81,82]. As discussed before, none of the new marker molecules was shown to be superior to conventional histological classification in larger studies and has found its way into conventional diagnostic yet. Until today, Clark level and tumour thickness are still the factors with best prognostic significance. However, biomarkers for defined problems in analysis of malignant melanoma have to be established. Important problems are (1) the differentiation between naevi, dysplastic naevi and melanoma, (2) definition of prognosis (high risk patients) and (3) search for the best therapeutic option. Several new markers will arise from large array studies in near future [35,83]. Detailed analysis by studies using new highthroughput techniques like multiple tissue arrays are needed to verify and establish these markers. These newly identified proteins that correlate with melanoma development have, of course, an important functional role in tumour development or progression. However, whether these proteins are really good markers to answer the questions mentioned above as suggested by the studies cited in this review and help to aid melanoma identification, prognostication, and detection of minimal residual disease/early recurrence has to be shown. Moreover, only few therapeutic options exist for melanoma as no regimen prolongs survival. Emerging data with investigational therapies suggest that certain markers might play a crucial role in identifying patients who will respond to therapy or show utility in monitoring the response to therapy. Herein, molecular diagnostics can potentially be beneficial for the individual melanoma patient.
34
A.K. Bosserhoff / Clinica Chimica Acta 367 (2006) 28 – 35
References [1] Ranuncolo SM, Ladeda V, Gorostidy S, et al. Expression of CD44s and CD44 splice variants in human melanoma. Oncol Rep 2002;9:51 – 6. [2] Chana JS, Grover R, Tulley P, et al. The c-myc oncogene: use of a biological prognostic marker as a potential target for gene therapy in melanoma. Br J Plast Surg 2002;55:623 – 7. [3] Sarris M, Scolyer RA, Konopka M, Thompson JF, Harper CG, Lee CS. Cytoplasmic expression of nm23 predicts the potential for cerebral metastasis in patients with primary cutaneous melanoma. Melanoma Res 2004;14:23 – 7. [4] Kageshita T, Hamby CV, Ishihara T, Matsumoto K, Saida T, Ono T. Loss of beta-catenin expression associated with disease progression in malignant melanoma. Br J Dermatol 2001;145:210 – 6. [5] Grover R, Pacifico MD, Wilson GD, Sanders R. Use of oncogene expression as an independent prognostic marker for primary melanoma. Ann Plast Surg 2003;50:183 – 7. [6] Haritopoulos KN, Lazaris AC, Kavantzas N, Tseleni-Balafouta S, Thomopoulou G, Aroni K. ICAM-1 and beta(3) integrin immunoexpression in malignant melanoma cells: can they be used as additional predictors? APMIS 2003;111:421 – 9. [7] Nikkola J, Vihinen P, Vlaykova T, Hahka-Kemppinen M, Heino J, Pyrhonen S. Integrin chains beta1 and alphav as prognostic factors in human metastatic melanoma. Melanoma Res 2004;14: 29 – 37. [8] Weeraratna AT. A Wnt-er Wonderland—The complexity of Wnt signaling in melanoma. Cancer Metastasis Rev 2005;24:237 – 50. [9] Gray-Schopfer VC, da Rocham DS, Marais R. The role of B-RAF in melanoma. Cancer Metastasis Rev 2005;24:165 – 83. [10] Robertson GP. Functional and therapeutic significance of Akt deregulation in malignant melanoma. Cancer Metastasis Rev 2005; 24:273 – 85. [11] Dai DL, Martinka M, Li G. Prognostic significance of activated Akt expression in melanoma: a clinicopathologic study of 292 cases. J Clin Oncol 2005;23:1473 – 82. [12] Straume O, Akslen LA. Importance of vascular phenotype by basic fibroblast growth factor, and influence of the angiogenic factors basic fibroblast growth factor/fibroblast growth factor receptor-1 and ephrin-A1/EphA2 on melanoma progression. Am J Pathol 2002; 160:1009 – 19. [13] Easty DJ, Hill SP, Hsu MY, et al. Up-regulation of ephrin-A1 during melanoma progression. Int J Cancer 1999;84:494 – 501. [14] Hussein MR, Haemel AK, Wood GS. Apoptosis and melanoma: molecular mechanisms. J Pathol 2003;199:275 – 88. [15] Lindholm D, Arumae U. Cell differentiation: reciprocal regulation of Apaf-1 and the inhibitor of apoptosis proteins. J Cell Biol 2004; 167:193 – 5. [16] Cain K, Bratton SB, Cohen GM. The Apaf-1 apoptosome: a large caspase-activating complex. Biochimie 2002;84:203 – 14. [17] Soengas MS, Capodieci P, Polsky D, et al. Inactivation of the apoptosis effector Apaf-1 in malignant melanoma. Nature 2001; 409:207 – 11. [18] Mustika R, Budiyanto A, Nishigori C, Ichihashi M, Ueda M. Decreased expression of Apaf-1 with progression of melanoma. Pigment Cell Res 2005;18:59 – 62. [19] Dai DL, Martinka M, Bush JA, Li G. Reduced Apaf-1 expression in human cutaneous melanomas. Br J Cancer 2004;91:1089 – 95. [20] Baldi A, Santini D, Russo P, et al. Analysis of APAF-1 expression in human cutaneous melanoma progression. Exp Dermatol 2004;13: 93 – 7. [21] Cory S, Huang DC, Adams JM. The Bcl-2 family: roles in cell survival and oncogenesis. Oncogene 2003;22:8590 – 607. [22] Cerroni L, Soyer HP, Kerl H. Bcl-2 protein expression in cutaneous malignant melanoma and benign melanocytic nevi. Am J Dermatopathol 1995;17:7 – 11.
[23] Vlaykova T, Talve L, Hahka-Kemppinen M, et al. Immunohistochemically detectable bcl-2 expression in metastatic melanoma: association with survival and treatment response. Oncology 2002; 62:259 – 68. [24] Divito KA, Berger AJ, Camp RL, Dolled-Filhart M, Rimm DL, Kluger HM. Automated quantitative analysis of tissue microarrays reveals an association between high Bcl-2 expression and improved outcome in melanoma. Cancer Res 2004;64:8773 – 7. [25] Moon RT, Bowerman B, Boutros M, Perrimon N. The promise and perils of Wnt signaling through beta-catenin. Science 2002;296: 1644 – 6. [26] Morin PJ. Beta-catenin signaling and cancer. Bioessays 1999;21: 1021 – 30. [27] Kielhorn E, Provost E, Olsen D, et al. Tissue microarray-based analysis shows phospho-beta-catenin expression in malignant melanoma is associated with poor outcome. Int J Cancer 2003;20(103): 652 – 6. [28] Kuphal S, Bauer R, Bosserhoff AK. Integrin signaling in malignant melanoma. Cancer Metastasis Rev 2005;24:195 – 222. [29] Haass NK, Smalley KS, Li L, Herlyn M. Adhesion, migration and communication in melanocytes and melanoma. Pigment Cell Res 2005;18:150 – 9. [30] Pacifico MD, Grover R, Richman PI, Daley FM, Buffa F, Wilson GD. Development of a tissue array for primary melanoma with long-term follow-up: discovering melanoma cell adhesion molecule as an important prognostic marker. Plast Reconstr Surg 2005;115:367 – 75. [31] Volpert O, Luo W, Liu TJ, Estrera VT, Logothetis C, Lin SH. Inhibition of prostate tumor angiogenesis by the tumor suppressor CEACAM1. J Biol Chem 2002;277:35696 – 702. [32] Busch C, Hanssen TA, Wagener C, OBrink B. Down-regulation of CEACAM1 in human prostate cancer: correlation with loss of cell polarity, increased proliferation rate, and Gleason grade 3 to 4 transition. Hum Pathol 2002;33:290 – 8. [33] Thies A, Moll I, Berger J, et al. CEACAM1 expression in cutaneous malignant melanoma predicts the development of metastatic disease. J Clin Oncol 2002;20:2530 – 6. [34] Ebrahimnejad A, Streichert T, Nollau P, et al. CEACAM1 enhances invasion and migration of melanocytic and melanoma cells. Am J Pathol 2004;165:1781 – 7. [35] Hoek K, Rimm DL, Williams KR, et al. Expression profiling reveals novel pathways in the transformation of melanocytes to melanomas. Cancer Res 2004;64:5270 – 82. [36] Bauer R, Hein R, Bosserhoff AK. A secreted form of P-cadherin is expressed in malignant melanoma. Exp Cell Res 2005;305: 418 – 426. [37] Pacifico MD, Grover R, Richman PI, Buffa F, Daley FM, Wilson GD. Identification of P-cadherin in primary melanoma using a tissue microarrayer: prognostic implications in a patient cohort with longterm follow up. Ann Plast Surg 2005;55:316 – 20. [38] Murakami T, Cardones AR, Hwang ST. Chemokine receptors and melanoma metastasis. J Dermatol Sci 2004;36:71 – 8. [39] Payne AS, Cornelius LA. The role of chemokines in melanoma tumor growth and metastasis. J Invest Dermatol 2002;118:915 – 22. [40] Scala S, Ottaiano A, Ascierto PA, et al. Expression of CXCR4 predicts poor prognosis in patients with malignant melanoma. Clin Cancer Res 2005;11:1835 – 41. [41] Longo-Imedio MI, Longo N, Trevino I, Lazaro P, Sanchez-Mateos P. Clinical significance of CXCR3 and CXCR4 expression in primary melanoma. Int J Cancer 2005;117:861 – 5. [42] Simon LS. Role and regulation of cyclooxygenase-2 during inflammation. Am J Med 1999;106:37S – 42S. [43] Ristimaki A. Cyclooxygenase 2: from inflammation to carcinogenesis. Novartis Found Symp 2004;256:215 – 21 [discussion 221-6, 25969.:215-21]. [44] Denkert C, Kobel M, Berger S, et al. Expression of cyclooxygenase 2 in human malignant melanoma. Cancer Res 2001;61:303 – 8.
A.K. Bosserhoff / Clinica Chimica Acta 367 (2006) 28 – 35 [45] Goulet AC, Einsphar JG, Alberts DS, et al. Analysis of cyclooxygenase 2 (COX-2) expression during malignant melanoma progression. Cancer Biol Ther 2003;2:713 – 8. [46] Poser I, Bosserhoff AK. Transcription factors involved in development and progression of malignant melanoma. Histol Histopathol 2004;19: 173 – 88. [47] Sato Y. Role of ETS family transcription factors in vascular development and angiogenesis. Cell Struct Funct 2001;26:19 – 24. [48] Macleod K, Leprince D, Stehelin D. The ets gene family. Trends Biochem Sci 1992;17:251 – 6. [49] Rothhammer T, Hahne JC, Florin A, et al. The Ets-1 transcription factor is involved in the development and invasion of malignant melanoma. Cell Mol Life Sci 2004;61:118 – 28. [50] Torlakovic EE, Bilalovic N, Nesland JM, Torlakovic G, Florenes VA. Ets-1 transcription factor is widely expressed in benign and malignant melanocytes and its expression has no significant association with prognosis. Mod Pathol 2004;17:1400 – 6. [51] Keehn CA, Smoller BR, Morgan MB. Expression of the ets-1 proto-oncogene in melanocytic lesions. Mod Pathol 2003; 16:772 – 7. [52] Dery MA, Michaud MD, Richard DE. Hypoxia-inducible factor 1: regulation by hypoxic and non-hypoxic activators. Int J Biochem Cell Biol 2005;37:535 – 40. [53] Kim WY, Kaelin WG. Role of VHL gene mutation in human cancer. J Clin Oncol 2004;22:4991 – 5004. [54] Brahimi-Horn MC, Pouyssegur J. The hypoxia-inducible factor and tumor progression along the angiogenic pathway. Int Rev Cytol 2005; 242:157 – 213. [55] Liu L, Simon MC. Regulation of transcription and translation by hypoxia. Cancer Biol Ther 2004;3:492 – 7. [56] Giatromanolaki A, Sivridis E, Kouskoukis C, Gatter KC, Harris AL, Koukourakis MI. Hypoxia-inducible factors 1alpha and 2alpha are related to vascular endothelial growth factor expression and a poorer prognosis in nodular malignant melanomas of the skin. Melanoma Res 2003;13:493 – 501. [57] Steingrimsson E, Copeland NG, Jenkins NA. Melanocytes and the microphthalmia transcription factor network. Annu Rev Genet 2004; 38:365 – 411. [58] Widlund HR, Fisher DE. Microphthalamia-associated transcription factor: a critical regulator of pigment cell development and survival. Oncogene 2003;22:3035 – 41. [59] Goding CR. Mitf from neural crest to melanoma: signal transduction and transcription in the melanocyte lineage. Genes Dev 2000;14: 1712 – 28. [60] Vachtenheim J, Borovansky J. Microphthalmia transcription factor: a specific marker for malignant melanoma. Prague Med Rep 2004; 105:318 – 24. [61] Salti GI, Manougian T, Farolan M, Shilkaitis A, Majumdar D, Das Gupta TK. Micropthalmia transcription factor: a new prognostic marker in intermediate-thickness cutaneous malignant melanoma. Cancer Res 2000;60:5012 – 6. [62] Dorvault CC, Weilbaecher KN, Yee H, et al. Microphthalmia transcription factor: a sensitive and specific marker for malignant melanoma in cytologic specimens. Cancer 2001;93:337 – 43. [63] Granter SR, Weilbaecher KN, Quigley C, Fisher DE. Role for microphthalmia transcription factor in the diagnosis of metastatic malignant melanoma. Appl Immunohistochem Mol Morphol 2002; 10:47 – 51.
35
[64] King R, Googe PB, Weilbaecher KN, Mihm Jr MC, Fisher DE. Microphthalmia transcription factor expression in cutaneous benign, malignant melanocytic, and nonmelanocytic tumors. Am J Surg Pathol 2001;25:51 – 7. [65] Behrmann I, Wallner S, Komyod W, et al. Characterization of methylthioadenosin phosphorylase (MTAP) expression in malignant melanoma. Am J Pathol 2003;163:683 – 90. [66] Seykora JT, Jih D, Elenitsas R, Horng WH, Elder DE. Gene expression profiling of melanocytic lesions. Am J Dermatopathol 2003;25:6 – 11. [67] Zhang N, Deuel TF. Pleiotrophin and midkine, a family of mitogenic and angiogenic heparin-binding growth and differentiation factors. Curr Opin Hematol 1999;6:44 – 50. [68] Kurtz A, Schulte AM, Wellstein A. Pleiotrophin and midkine in normal development and tumor biology. Crit Rev Oncog 1995;6: 151 – 77. [69] Wu H, Barusevicius A, Babb J, et al. Pleiotrophin expression correlates with melanocytic tumor progression and metastatic potential. J Cutan Pathol 2005;32:125 – 30. [70] Toyoshima-Morimoto F, Taniguchi E, Shinya N, Iwamatsu A, Nishida E. Polo-like kinase 1 phosphorylates cyclin B1 and targets it to the nucleus during prophase. Nature 2001;410:215 – 20. [71] Smith MR, Wilson ML, Hamanaka R, et al. Malignant transformation of mammalian cells initiated by constitutive expression of the pololike kinase. Biochem Biophys Res Commun 1997;234:397 – 405. [72] Kneisel L, Strebhardt K, Bernd A, Wolter M, Binder A, Kaufmann R. Expression of polo-like kinase (PLK1) in thin melanomas: a novel marker of metastatic disease. J Cutan Pathol 2002; 29:354 – 8. [73] Yu J, Zhang L. No PUMA, no death: implications for p53-dependent apoptosis. Cancer Cell 2003;4:248 – 9. [74] Puthalakath H, Strasser A. Keeping killers on a tight leash: transcriptional and post-translational control of the pro-apoptotic activity of BH3-only proteins. Cell Death Differ 2002;9:505 – 12. [75] Karst AM, Dai DL, Martinka M, Li G. PUMA expression is significantly reduced in human cutaneous melanomas. Oncogene 2005;24:1111 – 6. [76] Tan JC, Rabkin R. Suppressors of cytokine signaling in health and disease. Pediatr Nephrol 2005;20:567 – 75. [77] Leroith D, Nissley P. Knock your SOCS off!. J Clin Invest 2005;115:233 – 6. [78] Fujimoto M, Naka T. Regulation of cytokine signaling by SOCS family molecules. Trends Immunol 2003;24:659 – 66. [79] Li Z, Metze D, Nashan D, et al. Expression of SOCS-1, suppressor of cytokine signalling-1, in human melanoma. J Invest Dermatol 2004;123:737 – 45. [80] Pham K, Milovanovic T, Barr RJ, Truong T, Holcombe RF. Wnt ligand expression in malignant melanoma: pilot study indicating correlation with histopathological features. Mol Pathol 2003;56: 280 – 5. [81] Meier F, Satyamoorthy K, Nesbit M, et al. Molecular events in melanoma development and progression. Front Biosci 1998;3: D1005 -10 – D1010. [82] Herlyn M. Human melanoma: development and progression. Cancer Metastasis Rev 1990;9:101 – 12. [83] Bittner M, Meltzer P, Chen Y, et al. Molecular classification of cutaneous malignant melanoma by gene expression profiling. Nature 2000;406:536 – 40.
Review
Novel biomarkers in malignant melanoma Anja K. Bosserhoff * Institute of Pathology, University of Regensburg, Franz-Josef-Strauss-Allee 11, D-93053 Regensburg, Germany Received 21 July 2005; received in revised form 25 October 2005; accepted 26 October 2005 Available online 9 February 2006
Abstract Cutaneous malignant melanoma remains the leading cause of skin cancer death in industrialized countries. Melanoma progression is well defined in its clinical and histopathological aspects (Breslow’s index, tumour size, ulceration, or vascular invasion), which also give hints to prognosis of the patient. Use of molecular markers should therefore give additional information which cannot be determined by routine histopathology. Markers showing only a correlation to Clark level or tumour size are not useful. Several molecules influencing invasiveness and metastatic dissemination of melanoma have been identified. Expression of these molecules has been studied in primary melanoma and correlated with prognosis. Moreover, several tumour suppressors and oncogenes have been shown to be involved in melanoma pathogenesis, including CDKN2A, PTEN, TP53, RAS and MYC, but have not been related to melanoma subtypes or validated as prognostic markers. In the past, in melanoma, an increase in the number of positive tumour cells for Ki67 (detected by Mib1), cyclin A, cyclin D, MMP-2, integrins beta1 and beta3 or osteonectin were considered as factors of poor prognosis as well as the decrease in p16, p27, and Melan A. However, only a small subset of these proteins has a prognostic value independent of tumour thickness. The recent development of high-throughput technologies analyzing global molecular profiles of cancer is bringing up previously unknown candidate genes involved in melanoma, such as Wnt-5A and B-raf. Here, recently published data related to new genes involved in melanoma pathogenesis, which may represent important biomarkers for the identification of genetic profiles or indication of progression of melanoma, are reviewed. D 2006 Elsevier B.V. All rights reserved. Keywords: Malignant melanoma; Biomarker; Prognosis; Candidate genes; Screening; Melanoma pathogenesis
Contents 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.
Introduction . . . . . . . . . . . . . . . . . . Phosphorylated AKT . . . . . . . . . . . . . . Angiogenic factors . . . . . . . . . . . . . . . Apaf-1 (apoptotic protease-activating factor-1). Bcl-2 . . . . . . . . . . . . . . . . . . . . . . h-Catenin. . . . . . . . . . . . . . . . . . . . Cell – cell and cell – matrix-adhesion molecules CXCR4. . . . . . . . . . . . . . . . . . . . . Cyclooxygenase-2 (COX-2) . . . . . . . . . . Ets-1 . . . . . . . . . . . . . . . . . . . . . . HIF (hypoxia-inducible factor) . . . . . . . . . MITF (microphthalmia associated factor) . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
* Tel.: +49 941 944 6705; fax: +49 941 944 6602. E-mail address: [email protected]. 0009-8981/$ - see front matter D 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.cca.2005.10.029
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
29 29 30 30 30 30 31 31 31 31 32 32
A.K. Bosserhoff / Clinica Chimica Acta 367 (2006) 28 – 35
13. MTAP (methylthioadenosine phosphorylase) . . . 14. Pleiotrophin . . . . . . . . . . . . . . . . . . . 15. PLK-1 (polo-like kinase 1) . . . . . . . . . . . . 16. PUMA (p53 upregulated modulator of apoptosis) 17. SOCS (suppressors of cytokine signalling). . . . 18. Wnts . . . . . . . . . . . . . . . . . . . . . . . 19. Summary . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
1. Introduction Cutaneous malignant melanoma remains the leading cause of skin cancer death in industrialized countries. Melanoma progression is well defined in its clinical and histopathological aspects (Breslow’s index, tumour size, ulceration, or vascular invasion), which also give hints to prognosis of the patient. Use of molecular markers should therefore give additional information which can not be determined by routine histopathology. Markers showing only a correlation to Clark level or tumour size are not useful. Several molecules influencing invasiveness and metastatic dissemination of melanoma have been identified. Expression of these molecules has been studied in primary melanoma and correlated with prognosis. Moreover, several tumour suppressors and oncogenes have been shown to be involved in melanoma pathogenesis, including CDKN2A, PTEN, TP53, RAS and MYC, but have not been related to melanoma subtypes or validated as prognostic markers. In the past in melanoma an increase in the number of positive tumour cells for Ki67 (detected by Mib1), cyclin A, cyclin D, MMP-2, integrins beta1 and beta3 or osteonectin were considered as factors of poor prognosis as well as the decrease in p16, p27, and Melan A [1– 7]. However, only a
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
29
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
32 32 32 33 33 33 33 34
small subset of these proteins has a prognostic value independent of tumour thickness. The recent development of high-throughput technologies analyzing global molecular profiles of cancer is bringing up previously unknown candidate genes involved in melanoma, such as Wnt-5A and B-raf [8,9]. Here, recently published data related to new genes involved in melanoma pathogenesis, which may represent important biomarkers for the identification of genetic profiles or indication of progression of melanoma are reviewed (genes are presented in alphabetical order). The main information is summarized in Table 1.
2. Phosphorylated AKT AKT (or protein kinase B (PKB)) is a serine/threonine kinase that leads to stimulation of cell cycle progression, cell proliferation, and inhibition of apoptosis [10]. Strong pAKT expression was observed in one study in the biopsies of 17% of normal naevi, 43% of dysplastic naevi, 49% of primary melanoma, and 77% of melanoma metastases, respectively [11]. Significant differences for p-AKT staining pattern were observed between normal naevi and primary melanomas and between primary melanomas and melanoma
Table 1 Overview on markers described Marker p-AKT Ephrin A1 Apaf-1 Bcl-2 h-Catenin CEACAM1 P-cadherin CXCR4 Cox-2 Ets-1 HIF MITF MTAP Pleiotrophin PLK-1 PUMA SOCS Wnts
Correlation with tumour thickness
Correlation with pathological stages
Correlation with survival
Independent prognostic marker
–
–
This table summarizes the data presented in the review (: was shown, – : could not be determined, empty field: not analysed).
30
A.K. Bosserhoff / Clinica Chimica Acta 367 (2006) 28 – 35
metastases, respectively, showing that activity of AKT increases dramatically with melanoma invasion and progression. Furthermore, Kaplan – Meier survival curves showed that strong AKT activity is inversely correlated with both overall and disease-specific 5-year survival of patients with primary melanoma. Multivariate Cox regression analysis revealed that p-AKT is an independent prognostic factor in low-risk melanomas. Therefore, pAKT is considered as an independent prognostic marker that may help to identify those patients with ‘‘so-called’’ low-risk melanomas who are actually at increased risk of death.
3. Angiogenic factors The expression of several angiogenic factors and receptors was examined in a series of vertical growth phase cutaneous melanomas using high-throughput tissue microarray technology and immunohistochemistry in a study by Straume and Akslen [12]. Expression of basic fibroblast growth factor (bFGF) was significantly associated with increased microvessel density in melanomas. Strong expression of FLT-4, ephrin-A1, and EphA2 (receptor for ephrin-A1) on tumour cell was associated with increased melanoma thickness, and ephrin-A1 staining was related to decreased survival. Expression of EphA2 in tumour cells was associated with increased tumour cell proliferation (Ki67 positivity), indicating possible autocrine growth stimulation. The use of Ephrin-A1 and EphA2 as biomarkers was also supported by another study of Easty et al. [13].
4. Apaf-1 (apoptotic protease-activating factor-1) The exact mechanism for failure in the apoptotic pathway in melanoma cells is unclear. p53, the most frequently mutated tumour suppressor gene in human cancers, is a key apoptosis inducer. However, p53 mutations are only found in 15– 20% of melanoma biopsies [14]. Apoptotic proteaseactivating factor-1 (Apaf-1) is a cell death effector that acts with cytochrom C and caspase-9 to mediate apoptosis [15,16]. Recently, it was shown that metastatic melanomas often lose Apaf-1 and are concomitantly resistant to apoptosis [17]. A significant decrease in Apaf-1 expression was observed when comparing naevi and melanomas. Moreover, primary melanomas with greater tumour thickness showed lesser expression of Apaf-1 and Apaf-1 expression in lesions of metastatic melanomas was undetectable. These data demonstrated that there is an inverse correlation between Apaf-1 expression and pathologic stage of melanoma [18]. Additional immunohistochemical studies gained equal results showing that Apaf-1 expression is significantly reduced in melanoma cells compared with normal naevi. An association of Apaf-1 and tumour thickness was discussed controversially [19,20].
5. Bcl-2 The Bcl-2 oncogene belongs to a new category of oncogenes that influence tissue homeostasis regulating cell death. The gene encodes for a protein that preserves cells from death by apoptosis, allowing them to survive in G0 phase even in the absence of essential growth factors [21]. The anti-apoptotic protein Bcl-2 is supposed to influence the treatment responsiveness of different malignancies. Diverse results found in the literature may be due to use of small cohorts or variability in staining technique [22]. The presence of Bcl-2 immunoreactivity was associated with a significantly reduced proliferation and a longer disease-free survival. In contrast, the lack of Bcl-2 expression was related to a higher response rate to therapy. The results support the role of Bcl-2 in the regulation of cell proliferation and suggest that an increase of metastatic potential and progression of malignant melanoma is associated with a loss of Bcl-2 expression [23]. These results were supported by a study of Divito et al. [24]. Here, high Bcl-2 expression was associated with better outcome in the entire cohort and among metastatic specimens. Expression was higher in primary than in metastatic specimens. 6. B-Catenin h-Catenin plays a crucial role in the function of cell adhesion molecules and also participates in growth regulatory signalling pathways that may be involved in malignant transformation [25,26]. h-Catenin expression was examined by immunochemical staining in a study by Kageshita et al. [4]. They found h-catenin expression in 96% of melanocytic naevi, in 94% and 65%, respectively, of radial and vertical growth phase of primary melanomas, and in 38% of metastatic melanomas. Absent or weak expression of hcatenin in primary melanomas was associated with several markers of disease progression, including tumour thickness and presence of lymph node metastases. Their results suggest that loss or downregulation of h-catenin expression in melanoma cells plays a significant role in progression of the disease. In another study antibodies specific to phosphorylated h-catenin were used [27]. Evaluation of phospho-h-catenin staining showed that cytoplasmic/nuclear staining was more common in primary lesions, whereas nuclear phospho-h-catenin was found more often in metastatic lesions. High levels of nuclear phospho-h-catenin are associated with significantly worse overall survival. These results suggest that phospho-specific antibodies to h-catenin identify a unique subset of cases with poor clinical outcome and that monitoring of phospho-h-catenin expression may be useful for assessing prognosis in malignant melanoma.
A.K. Bosserhoff / Clinica Chimica Acta 367 (2006) 28 – 35
31
7. Cell – cell and cell –matrix-adhesion molecules
8. CXCR4
Malignant melanoma usually progresses from the intraepidermal microenvironment through a distinct radial growth phase, in which malignant potential cannot always be accurately evaluated, to invasion of the dermis (vertical growth phase) and metastasis. During these stages malignant cells interact with each other and with the extracellular matrix. The expression pattern of integrin-type cell adhesion receptors is often changed during malignant transformation [28]. Next to several integrins, cadherins, MUC18, ICAM-1 and NCAM are known to be deregulated [29]. Haritopoulos et al. reported that ICAM-1 immunopositivity status was significantly more frequent among malignant melanomas of the nodular type, and was associated with the vertical growth phase, Breslow thickness of > 0.77 mm, and with evident lymphocytic infiltration. Integrin beta3 immunopositivity showed similar results in certain respects; it was more frequently detected in superficial spreading melanomas in which vertical growth had developed and in cases with regression [6,30]. The cell adhesion molecule CEACAM1 is involved in intercellular adhesion and subsequent signal transduction events in a number of epithelia. CEACAM1 downregulation has been demonstrated in colorectal and prostate carcinomas [31,32]. Interestingly, expression in malignant melanoma is associated with metastasis [33,34]. Often, the strongest CEACAM1 expression was observed at the invading front. In addition, CEACAM1 expression was preserved in the metastatic lesions. Kaplan –Meier analysis revealed a highly significant association between CEACAM1 expression and metastasis. Multivariate Cox regression analysis, including CEACAM1 expression status adjusted for tumour thickness, presence of ulceration, and mitotic rate, confirmed that CEACAM1 is an independent factor for the risk of metastasis and demonstrated that the predictive value of CEACAM1 expression is superior to that of tumour thickness. Therefore, expression of the cell adhesion molecule CEACAM1 in primary tumours in melanoma patients is associated with the subsequent development of metastatic disease. It was shown that membraneous P-cadherin expression is reduced or lost in malignant melanoma [35,36]. In a study of Pacifico et al. loss of P-cadherin expression was found to be significantly correlated with outcome [37]. A so far unpublished study using melanoma tissue microarrays revealed that, in general, P-cadherin expression was significantly reduced in malignant melanomas and melanoma metastases compared to benign naevi (Bauer et al., unpublished results). Additionally, loss of membranous Pcadherin was associated with Clark level and tumour thickness. Further, low P-cadherin expression was associated with tumour recurrence suggesting P-cadherin expression to be a predictive marker of progression in melanoma patients.
CXCR4 and its unique ligand, the CXCL12 chemokine, have been recently implicated in cancer metastasis [38,39]. Evidence about the role of CXCR4/CXCL12 axis has been reported in several cancers including melanoma. CXCR4 expression was reported to have a prognostic value in malignant melanoma [40,41]. The CXCR4 expression on tumour cells was correlated with an unfavorable prognosis. The expression of CXCR4 by melanoma cells in primary lesions was significantly associated with the presence of ulceration, increased tumour thickness, a greater risk of developing regional and distant metastases and a higher mortality rate. In multivariate analysis CXCR4 expression emerged as independent prognostic factors. Therefore, CXCR4 expression could be an independent and powerful prognostic marker in primary cutaneous malignant melanomas.
9. Cyclooxygenase-2 (COX-2) COX-2 is an inducible enzyme involved in production of prostaglandins in inflammatory processes [42]. There are now several lines of evidence indicating that increased expression of COX-2 plays a functional role in the development and progression of malignant cancers [43]. Denkert et al. investigated expression of COX-2 in cases of primary skin melanoma and benign naevi and detected expression in almost all melanoma but benign naevi as well as normal epithelium were negative in all cases [44]. In addition, Goulet et al. examined lesions through out the development of melanoma and metastatic disease (dysplastic naevi, melanoma in situ, stage II melanoma, stage III, stage IV, stage V, melanoma metastasis lymph nodes and metastasis to other sites) [45]. No COX-2 staining was detected in naevi. However, in contrast to the study of Denkert et al., COX-2 expression was not found in primary skin melanoma cells and in all vertical and radial growth phase cases. In contrast, all lymph node metastasis and metastatic cancer cells expressed high levels of COX-2. Collectively, these data suggest that COX-2 may play a functional role in metastases of melanoma, and treatment with COX-2 inhibitors may be efficacious for malignant melanoma.
10. Ets-1 Ets-1 oncoprotein is a transcription factor known to regulate the expression of numerous genes important in extracellular matrix remodeling and angiogenesis [46 – 48]. Ets-1 has been associated with tumour progression in various carcinomas, but its expression in malignant melanoma was only recently described [49]. Immunohistochemical studies revealed lower expression of Ets-1 in primary melanomas than in common naevi and further, in metastatic melanomas than in primary melanomas [50,51]. No association between
32
A.K. Bosserhoff / Clinica Chimica Acta 367 (2006) 28 – 35
Ets-1 expression and disease-specific survival or time to treatment failure, respectively, could be shown. In another study, however, increased staining in metastases compared to primary tumours, and in primary tumours compared to naevi was found. There was a trend toward more intense staining with melanoma progression. A statistically significant difference in the mean labeling intensity of Ets-1 was seen between invasive melanoma and benign melanocytic naevi. Therefore, Ets-1 expression cannot be used to differentiate between benign and malignant melanocytic lesions and it has no definite association with clinical outcome. Its role in tumour progression in some cases of malignant melanoma cannot be entirely excluded where Ets-1 expression may be an important pathogenic mechanism [49].
gression of melanocytic tumours as the amount of MTAP protein staining decreased from benign melanocytic naevi to metastatic melanomas [65]. In a multiple tissue array the prognostic value of MTAP expression was analyzed (own unpublished data). MTAP expression was significantly reduced in malignant melanomas and melanoma metastases compared to benign naevi. In primary melanomas, only a low Ki-67 labeling index < 5% was associated with MTAP protein expression. In an explorative subgroup analysis, considering 26 patients with MTAP positive melanomas and recorded tumour recurrence, patients with interferon therapy had a significant benefit compared to patients without interferon treatment. Therefore, MTAP protein expression could be a predictive marker of therapy resistance in melanoma patients with disease progression and treated with interferon.
11. HIF (hypoxia-inducible factor) Hypoxia is a key regulatory factor in tumour growth, activating angiogenesis, glycolysis and cell migration. It is readily recognized by the intracellular accumulation of hypoxia-inducible factor 1alpha (HIF1alpha) and HIF2alpha [52 –55]. HIF1alpha and HIF2alpha accumulation in malignant melanomas was directly correlated with VEGF expression [56]. High HIF2alpha expression in tumours was associated with poorer prognosis in both univariate and multivariate analyses. Therefore, HIF2alpha was suggested to be an important prognostic factor in melanoma.
12. MITF (microphthalmia associated factor) The transcription factor (MITF) is required for the formation of normal melanocytes during embryonic development and for the expression of pigment cell-specific markers, which are the downstream transcriptional targets of MITF [57 – 59]. Further, MITF seems to be crucial for the survival of malignant melanocytes. Recently, MITF was suggested as a marker of malignant melanoma [60]. Melanocyte-specific isoform of MITF appears to be a unique molecule in the differential diagnosis of melanocytic tumours. Loss of MITF expression correlated inversely with overall survival and disease-free survival suggesting that MITF may be a new molecular prognostic marker in patients with melanoma [61]. One study presented MITF as a sensitive and specific marker for malignant melanoma and hypothesized MITF to be superior to the current standard melanocytic markers, S-100 protein and HMB-45 antigen [62]. However, other studies could not verify the usefulness of MITF as biomarker [63,64].
13. MTAP (methylthioadenosine phosphorylase) Recent studies demonstrated a significant inverse association between MTAP protein expression and pro-
14. Pleiotrophin GENE expression profiling of melanoma and naevi tissue has demonstrated that pleiotrophin (PTN) is significantly overexpressed in human melanomas [66]. Pleiotrophin is also named heparin-binding neurite outgrowth-promoting factor being a member of a highly conserved human gene family of proteins. It exhibits neurite outgrowth-promoting activity and may play a role in nervous tissue development and/or maintenance [67,68]. By immunohistochemistry melanocytic naevi were shown to be consistently negative, whereas the great majority of metastatic melanomas were positive [69]. Within the primary melanomas, PTN immunoreactivity was associated with metastasis and decreased melanoma-related survival. As PTN expression is associated with metastatic potential, PTN may be a prognostic factor for melanomas.
15. PLK-1 (polo-like kinase 1) Polo-like kinase 1 (PLK-1) is involved in regulating mitotic spindle function. Microinjection of PLK mRNA induced mitosis in quiescent cells [70]. Constitutive expression of PLK caused cells to proliferate in low serum media and cells transformed with PLK grew in soft agar and produced tumours in nude mice [71]. Therefore, PLK may be involved in the promotion or progression of cancers. In a recent study Kneisel et al. examined thin malignant melanomas with immunohistochemical techniques using monoclonal antibodies directed against PLK1 [72]. Malignant melanomas with metastases expressed PLK1 at markedly elevated levels compared to melanomas without metastases. These preliminary data suggest that PLK1 expression in thin melanomas may be a reliable marker to identify patients at high risk for metastases.
A.K. Bosserhoff / Clinica Chimica Acta 367 (2006) 28 – 35
16. PUMA (p53 upregulated modulator of apoptosis) PUMA (p53 upregulated modulator of apoptosis, or Bcl2-binding component 3; BBC3) was shown to bind to Bcl-2, localize to the mitochondria to induce cytochrome C release, and activate the rapid induction of programmed cell death [14,73,74]. In a study by Karst et al. PUMA expression was analyzed in primary melanomas, metastatic melanomas, and dysplastic naevi [75]. PUMA expression was significantly weaker in primary melanomas compared to dysplastic naevi and is further reduced in metastatic melanomas compared to primary tumours. Weak PUMA expression in melanoma correlated with poorer overall and disease-specific 5-year survival of melanoma patients showing PUMA expression in tumour tissue as an independent predictor of both overall and disease-specific 5-year survival. Additionally, it was shown that exogenous PUMA expression in human melanoma cell lines (both wild type and mutant p53) results in significant apoptotic cell death.
17. SOCS (suppressors of cytokine signalling) Cytokines induce a variety of biologic responses by binding to specific cell surface receptors and activating cytoplasmic signal transduction pathways. Cytokine resistance is a well-established feature of melanoma cell progression and represents also a major obstacle in immunotherapy of patients with metastatic melanoma. SOCS-1, an established negative regulator of interleukin6 (IL-6) and interferon (IFN) signalling, could play a crucial role in this process [76 – 78]. Recently, Li et al. analyzed whether SOCS play a role in cytokine resistance and tumour progression of melanoma [79]. Aberrant SOCS-1 protein expression in melanoma cells in vitro and in situ was shown by immunohistochemical analysis. SOCS-1 immunoreactivity was closely related to tumour invasion (Clark level), tumour thickness, and stage of the disease. In contrast, melanocytes in normal skin or melanocytic naevi lacked SOCS-1 protein expression. SOCS-1 seems to be a progression marker of human melanoma and may downregulate biological responses by endogenous and/or therapeutically administered cytokines.
18. Wnts Secreted Wnt ligands are key proteins regulating cell – cell interactions and cell growth and differentiation. These proteins, along with other components of the Wnt signaling pathway, are involved in the malignant transformation of various human cancers, including malignant melanoma [8]. As development of antibodies only started a first study was performed by in situ hybridization.
33
Pham et al. analysed expression of several members of the Wnt ligand family and correlated expression with histological characteristics [80]. All naevi tested strongly expressed Wnt2, Wnt5a, Wnt7b, and Wnt10b. Melanomas characterized by small, uniform cells expressed each of the Wnts in a pattern similar to that seen for benign naevi. In contrast, melanomas characterized by large, pleomorphic cells expressed Wnt10b but did not express Wnt2 and had low levels of expression of Wnt5a. Expression of Wnt7b was variable in these melanomas. The expression pattern of Wnt ligands in malignant melanoma correlates with histopathological features and may provide a basis for the molecular classification of this disease.
19. Summary Melanoma is a complex multigenic disease which is determined by several parallel and stepwise progressive pathways affecting growth control, differentiation, cell adhesion, and survival. Melanoma and human cancers in general undergo a continuous development from benign to malignant states, as most thoroughly documented in the multi-step naevi-to-melanoma transition [81,82]. As discussed before, none of the new marker molecules was shown to be superior to conventional histological classification in larger studies and has found its way into conventional diagnostic yet. Until today, Clark level and tumour thickness are still the factors with best prognostic significance. However, biomarkers for defined problems in analysis of malignant melanoma have to be established. Important problems are (1) the differentiation between naevi, dysplastic naevi and melanoma, (2) definition of prognosis (high risk patients) and (3) search for the best therapeutic option. Several new markers will arise from large array studies in near future [35,83]. Detailed analysis by studies using new highthroughput techniques like multiple tissue arrays are needed to verify and establish these markers. These newly identified proteins that correlate with melanoma development have, of course, an important functional role in tumour development or progression. However, whether these proteins are really good markers to answer the questions mentioned above as suggested by the studies cited in this review and help to aid melanoma identification, prognostication, and detection of minimal residual disease/early recurrence has to be shown. Moreover, only few therapeutic options exist for melanoma as no regimen prolongs survival. Emerging data with investigational therapies suggest that certain markers might play a crucial role in identifying patients who will respond to therapy or show utility in monitoring the response to therapy. Herein, molecular diagnostics can potentially be beneficial for the individual melanoma patient.
34
A.K. Bosserhoff / Clinica Chimica Acta 367 (2006) 28 – 35
References [1] Ranuncolo SM, Ladeda V, Gorostidy S, et al. Expression of CD44s and CD44 splice variants in human melanoma. Oncol Rep 2002;9:51 – 6. [2] Chana JS, Grover R, Tulley P, et al. The c-myc oncogene: use of a biological prognostic marker as a potential target for gene therapy in melanoma. Br J Plast Surg 2002;55:623 – 7. [3] Sarris M, Scolyer RA, Konopka M, Thompson JF, Harper CG, Lee CS. Cytoplasmic expression of nm23 predicts the potential for cerebral metastasis in patients with primary cutaneous melanoma. Melanoma Res 2004;14:23 – 7. [4] Kageshita T, Hamby CV, Ishihara T, Matsumoto K, Saida T, Ono T. Loss of beta-catenin expression associated with disease progression in malignant melanoma. Br J Dermatol 2001;145:210 – 6. [5] Grover R, Pacifico MD, Wilson GD, Sanders R. Use of oncogene expression as an independent prognostic marker for primary melanoma. Ann Plast Surg 2003;50:183 – 7. [6] Haritopoulos KN, Lazaris AC, Kavantzas N, Tseleni-Balafouta S, Thomopoulou G, Aroni K. ICAM-1 and beta(3) integrin immunoexpression in malignant melanoma cells: can they be used as additional predictors? APMIS 2003;111:421 – 9. [7] Nikkola J, Vihinen P, Vlaykova T, Hahka-Kemppinen M, Heino J, Pyrhonen S. Integrin chains beta1 and alphav as prognostic factors in human metastatic melanoma. Melanoma Res 2004;14: 29 – 37. [8] Weeraratna AT. A Wnt-er Wonderland—The complexity of Wnt signaling in melanoma. Cancer Metastasis Rev 2005;24:237 – 50. [9] Gray-Schopfer VC, da Rocham DS, Marais R. The role of B-RAF in melanoma. Cancer Metastasis Rev 2005;24:165 – 83. [10] Robertson GP. Functional and therapeutic significance of Akt deregulation in malignant melanoma. Cancer Metastasis Rev 2005; 24:273 – 85. [11] Dai DL, Martinka M, Li G. Prognostic significance of activated Akt expression in melanoma: a clinicopathologic study of 292 cases. J Clin Oncol 2005;23:1473 – 82. [12] Straume O, Akslen LA. Importance of vascular phenotype by basic fibroblast growth factor, and influence of the angiogenic factors basic fibroblast growth factor/fibroblast growth factor receptor-1 and ephrin-A1/EphA2 on melanoma progression. Am J Pathol 2002; 160:1009 – 19. [13] Easty DJ, Hill SP, Hsu MY, et al. Up-regulation of ephrin-A1 during melanoma progression. Int J Cancer 1999;84:494 – 501. [14] Hussein MR, Haemel AK, Wood GS. Apoptosis and melanoma: molecular mechanisms. J Pathol 2003;199:275 – 88. [15] Lindholm D, Arumae U. Cell differentiation: reciprocal regulation of Apaf-1 and the inhibitor of apoptosis proteins. J Cell Biol 2004; 167:193 – 5. [16] Cain K, Bratton SB, Cohen GM. The Apaf-1 apoptosome: a large caspase-activating complex. Biochimie 2002;84:203 – 14. [17] Soengas MS, Capodieci P, Polsky D, et al. Inactivation of the apoptosis effector Apaf-1 in malignant melanoma. Nature 2001; 409:207 – 11. [18] Mustika R, Budiyanto A, Nishigori C, Ichihashi M, Ueda M. Decreased expression of Apaf-1 with progression of melanoma. Pigment Cell Res 2005;18:59 – 62. [19] Dai DL, Martinka M, Bush JA, Li G. Reduced Apaf-1 expression in human cutaneous melanomas. Br J Cancer 2004;91:1089 – 95. [20] Baldi A, Santini D, Russo P, et al. Analysis of APAF-1 expression in human cutaneous melanoma progression. Exp Dermatol 2004;13: 93 – 7. [21] Cory S, Huang DC, Adams JM. The Bcl-2 family: roles in cell survival and oncogenesis. Oncogene 2003;22:8590 – 607. [22] Cerroni L, Soyer HP, Kerl H. Bcl-2 protein expression in cutaneous malignant melanoma and benign melanocytic nevi. Am J Dermatopathol 1995;17:7 – 11.
[23] Vlaykova T, Talve L, Hahka-Kemppinen M, et al. Immunohistochemically detectable bcl-2 expression in metastatic melanoma: association with survival and treatment response. Oncology 2002; 62:259 – 68. [24] Divito KA, Berger AJ, Camp RL, Dolled-Filhart M, Rimm DL, Kluger HM. Automated quantitative analysis of tissue microarrays reveals an association between high Bcl-2 expression and improved outcome in melanoma. Cancer Res 2004;64:8773 – 7. [25] Moon RT, Bowerman B, Boutros M, Perrimon N. The promise and perils of Wnt signaling through beta-catenin. Science 2002;296: 1644 – 6. [26] Morin PJ. Beta-catenin signaling and cancer. Bioessays 1999;21: 1021 – 30. [27] Kielhorn E, Provost E, Olsen D, et al. Tissue microarray-based analysis shows phospho-beta-catenin expression in malignant melanoma is associated with poor outcome. Int J Cancer 2003;20(103): 652 – 6. [28] Kuphal S, Bauer R, Bosserhoff AK. Integrin signaling in malignant melanoma. Cancer Metastasis Rev 2005;24:195 – 222. [29] Haass NK, Smalley KS, Li L, Herlyn M. Adhesion, migration and communication in melanocytes and melanoma. Pigment Cell Res 2005;18:150 – 9. [30] Pacifico MD, Grover R, Richman PI, Daley FM, Buffa F, Wilson GD. Development of a tissue array for primary melanoma with long-term follow-up: discovering melanoma cell adhesion molecule as an important prognostic marker. Plast Reconstr Surg 2005;115:367 – 75. [31] Volpert O, Luo W, Liu TJ, Estrera VT, Logothetis C, Lin SH. Inhibition of prostate tumor angiogenesis by the tumor suppressor CEACAM1. J Biol Chem 2002;277:35696 – 702. [32] Busch C, Hanssen TA, Wagener C, OBrink B. Down-regulation of CEACAM1 in human prostate cancer: correlation with loss of cell polarity, increased proliferation rate, and Gleason grade 3 to 4 transition. Hum Pathol 2002;33:290 – 8. [33] Thies A, Moll I, Berger J, et al. CEACAM1 expression in cutaneous malignant melanoma predicts the development of metastatic disease. J Clin Oncol 2002;20:2530 – 6. [34] Ebrahimnejad A, Streichert T, Nollau P, et al. CEACAM1 enhances invasion and migration of melanocytic and melanoma cells. Am J Pathol 2004;165:1781 – 7. [35] Hoek K, Rimm DL, Williams KR, et al. Expression profiling reveals novel pathways in the transformation of melanocytes to melanomas. Cancer Res 2004;64:5270 – 82. [36] Bauer R, Hein R, Bosserhoff AK. A secreted form of P-cadherin is expressed in malignant melanoma. Exp Cell Res 2005;305: 418 – 426. [37] Pacifico MD, Grover R, Richman PI, Buffa F, Daley FM, Wilson GD. Identification of P-cadherin in primary melanoma using a tissue microarrayer: prognostic implications in a patient cohort with longterm follow up. Ann Plast Surg 2005;55:316 – 20. [38] Murakami T, Cardones AR, Hwang ST. Chemokine receptors and melanoma metastasis. J Dermatol Sci 2004;36:71 – 8. [39] Payne AS, Cornelius LA. The role of chemokines in melanoma tumor growth and metastasis. J Invest Dermatol 2002;118:915 – 22. [40] Scala S, Ottaiano A, Ascierto PA, et al. Expression of CXCR4 predicts poor prognosis in patients with malignant melanoma. Clin Cancer Res 2005;11:1835 – 41. [41] Longo-Imedio MI, Longo N, Trevino I, Lazaro P, Sanchez-Mateos P. Clinical significance of CXCR3 and CXCR4 expression in primary melanoma. Int J Cancer 2005;117:861 – 5. [42] Simon LS. Role and regulation of cyclooxygenase-2 during inflammation. Am J Med 1999;106:37S – 42S. [43] Ristimaki A. Cyclooxygenase 2: from inflammation to carcinogenesis. Novartis Found Symp 2004;256:215 – 21 [discussion 221-6, 25969.:215-21]. [44] Denkert C, Kobel M, Berger S, et al. Expression of cyclooxygenase 2 in human malignant melanoma. Cancer Res 2001;61:303 – 8.
A.K. Bosserhoff / Clinica Chimica Acta 367 (2006) 28 – 35 [45] Goulet AC, Einsphar JG, Alberts DS, et al. Analysis of cyclooxygenase 2 (COX-2) expression during malignant melanoma progression. Cancer Biol Ther 2003;2:713 – 8. [46] Poser I, Bosserhoff AK. Transcription factors involved in development and progression of malignant melanoma. Histol Histopathol 2004;19: 173 – 88. [47] Sato Y. Role of ETS family transcription factors in vascular development and angiogenesis. Cell Struct Funct 2001;26:19 – 24. [48] Macleod K, Leprince D, Stehelin D. The ets gene family. Trends Biochem Sci 1992;17:251 – 6. [49] Rothhammer T, Hahne JC, Florin A, et al. The Ets-1 transcription factor is involved in the development and invasion of malignant melanoma. Cell Mol Life Sci 2004;61:118 – 28. [50] Torlakovic EE, Bilalovic N, Nesland JM, Torlakovic G, Florenes VA. Ets-1 transcription factor is widely expressed in benign and malignant melanocytes and its expression has no significant association with prognosis. Mod Pathol 2004;17:1400 – 6. [51] Keehn CA, Smoller BR, Morgan MB. Expression of the ets-1 proto-oncogene in melanocytic lesions. Mod Pathol 2003; 16:772 – 7. [52] Dery MA, Michaud MD, Richard DE. Hypoxia-inducible factor 1: regulation by hypoxic and non-hypoxic activators. Int J Biochem Cell Biol 2005;37:535 – 40. [53] Kim WY, Kaelin WG. Role of VHL gene mutation in human cancer. J Clin Oncol 2004;22:4991 – 5004. [54] Brahimi-Horn MC, Pouyssegur J. The hypoxia-inducible factor and tumor progression along the angiogenic pathway. Int Rev Cytol 2005; 242:157 – 213. [55] Liu L, Simon MC. Regulation of transcription and translation by hypoxia. Cancer Biol Ther 2004;3:492 – 7. [56] Giatromanolaki A, Sivridis E, Kouskoukis C, Gatter KC, Harris AL, Koukourakis MI. Hypoxia-inducible factors 1alpha and 2alpha are related to vascular endothelial growth factor expression and a poorer prognosis in nodular malignant melanomas of the skin. Melanoma Res 2003;13:493 – 501. [57] Steingrimsson E, Copeland NG, Jenkins NA. Melanocytes and the microphthalmia transcription factor network. Annu Rev Genet 2004; 38:365 – 411. [58] Widlund HR, Fisher DE. Microphthalamia-associated transcription factor: a critical regulator of pigment cell development and survival. Oncogene 2003;22:3035 – 41. [59] Goding CR. Mitf from neural crest to melanoma: signal transduction and transcription in the melanocyte lineage. Genes Dev 2000;14: 1712 – 28. [60] Vachtenheim J, Borovansky J. Microphthalmia transcription factor: a specific marker for malignant melanoma. Prague Med Rep 2004; 105:318 – 24. [61] Salti GI, Manougian T, Farolan M, Shilkaitis A, Majumdar D, Das Gupta TK. Micropthalmia transcription factor: a new prognostic marker in intermediate-thickness cutaneous malignant melanoma. Cancer Res 2000;60:5012 – 6. [62] Dorvault CC, Weilbaecher KN, Yee H, et al. Microphthalmia transcription factor: a sensitive and specific marker for malignant melanoma in cytologic specimens. Cancer 2001;93:337 – 43. [63] Granter SR, Weilbaecher KN, Quigley C, Fisher DE. Role for microphthalmia transcription factor in the diagnosis of metastatic malignant melanoma. Appl Immunohistochem Mol Morphol 2002; 10:47 – 51.
35
[64] King R, Googe PB, Weilbaecher KN, Mihm Jr MC, Fisher DE. Microphthalmia transcription factor expression in cutaneous benign, malignant melanocytic, and nonmelanocytic tumors. Am J Surg Pathol 2001;25:51 – 7. [65] Behrmann I, Wallner S, Komyod W, et al. Characterization of methylthioadenosin phosphorylase (MTAP) expression in malignant melanoma. Am J Pathol 2003;163:683 – 90. [66] Seykora JT, Jih D, Elenitsas R, Horng WH, Elder DE. Gene expression profiling of melanocytic lesions. Am J Dermatopathol 2003;25:6 – 11. [67] Zhang N, Deuel TF. Pleiotrophin and midkine, a family of mitogenic and angiogenic heparin-binding growth and differentiation factors. Curr Opin Hematol 1999;6:44 – 50. [68] Kurtz A, Schulte AM, Wellstein A. Pleiotrophin and midkine in normal development and tumor biology. Crit Rev Oncog 1995;6: 151 – 77. [69] Wu H, Barusevicius A, Babb J, et al. Pleiotrophin expression correlates with melanocytic tumor progression and metastatic potential. J Cutan Pathol 2005;32:125 – 30. [70] Toyoshima-Morimoto F, Taniguchi E, Shinya N, Iwamatsu A, Nishida E. Polo-like kinase 1 phosphorylates cyclin B1 and targets it to the nucleus during prophase. Nature 2001;410:215 – 20. [71] Smith MR, Wilson ML, Hamanaka R, et al. Malignant transformation of mammalian cells initiated by constitutive expression of the pololike kinase. Biochem Biophys Res Commun 1997;234:397 – 405. [72] Kneisel L, Strebhardt K, Bernd A, Wolter M, Binder A, Kaufmann R. Expression of polo-like kinase (PLK1) in thin melanomas: a novel marker of metastatic disease. J Cutan Pathol 2002; 29:354 – 8. [73] Yu J, Zhang L. No PUMA, no death: implications for p53-dependent apoptosis. Cancer Cell 2003;4:248 – 9. [74] Puthalakath H, Strasser A. Keeping killers on a tight leash: transcriptional and post-translational control of the pro-apoptotic activity of BH3-only proteins. Cell Death Differ 2002;9:505 – 12. [75] Karst AM, Dai DL, Martinka M, Li G. PUMA expression is significantly reduced in human cutaneous melanomas. Oncogene 2005;24:1111 – 6. [76] Tan JC, Rabkin R. Suppressors of cytokine signaling in health and disease. Pediatr Nephrol 2005;20:567 – 75. [77] Leroith D, Nissley P. Knock your SOCS off!. J Clin Invest 2005;115:233 – 6. [78] Fujimoto M, Naka T. Regulation of cytokine signaling by SOCS family molecules. Trends Immunol 2003;24:659 – 66. [79] Li Z, Metze D, Nashan D, et al. Expression of SOCS-1, suppressor of cytokine signalling-1, in human melanoma. J Invest Dermatol 2004;123:737 – 45. [80] Pham K, Milovanovic T, Barr RJ, Truong T, Holcombe RF. Wnt ligand expression in malignant melanoma: pilot study indicating correlation with histopathological features. Mol Pathol 2003;56: 280 – 5. [81] Meier F, Satyamoorthy K, Nesbit M, et al. Molecular events in melanoma development and progression. Front Biosci 1998;3: D1005 -10 – D1010. [82] Herlyn M. Human melanoma: development and progression. Cancer Metastasis Rev 1990;9:101 – 12. [83] Bittner M, Meltzer P, Chen Y, et al. Molecular classification of cutaneous malignant melanoma by gene expression profiling. Nature 2000;406:536 – 40.