- Email: [email protected]
565 Effects of melanoma derived exosomes on peritumoral stromal cells
Melanoma and Other Skin Cancers | ABSTRACTS 564
565
Role of CC-chemokine Receptor 6 (CCR6) and CC Ligand 20 (CCL20) mediated immunosurveillance in malignant melanoma D Martin-Garcia, A Enk and A Lonsdorf Department of Dermatology, University Hospital Heidelberg, Heidelberg, Germany Chemokine ligand 20 (CCL20) expressed in the epidermis are a potent impetus for the recruitment of subsets of dendritic cells (DC), B-cells and memory T cells expressing chemokine receptor 6 (CCR6), its exclusive receptor. CCL20 and a corresponding CCR6expressing immune cell infiltrate have been detected in several malignancies, including melanoma. Yet, the functional contribution of the CCR6/CCL20 axis for the immune control of melanoma remains controversial. The characterization of CCR6-guided immune cell subsets and their functional contribution for the immune control of melanoma comprises the focus of this project. We evaluated the homeostatic and inducible secretion of CCL20 by different murine and human melanoma cutaneous cell lines by enzyme-linked Immunoabsorbent assay (ELISA). Both, murine (B16, Ret) and human (A375, C32) melanoma cell lines are capable of secreting CCL20 upon stimulation with pro-inflammatory cytokines (i.e. TNFa, IL-1a, IL-1b and TGF-b) in vitro. In order to determine the functional relevance of CCR6 on local tumor growth, B16 melanoma cells retrovirally transduced with a vector that constantly overexpresses CCL20 (B16-CCL20) were injected subcutaneously in wild type C57BL/6 (WT) and congenic CCR6eknockout (CCR6KO) mice. While animals in both groups developed local tumors, we observed a significantly reduced tumor growth in CCR6KO mice. By contrast, WT and CCR6KO control groups (injected with a B16 line that does not express CCL20) did not display differences in tumor growth rate. In vitro data excludes the possibility of an autocrine apoptotic pathway. While the precise mechanisms require further investigation, our results suggest that CCL20 interactions in the microenvironment of cutaneous melanoma may be an essential factor for local tumor growth. Current experimental approaches focus on the identification of the local immune infiltrate by means of Fluorescence activated cells shorting (FACS) and expression of CCR6 and CCL20 in cutaneous melanoma of both WT and CCR6KO mice by means of real-time PCR.
Effects of melanoma derived exosomes on peritumoral stromal cells T Buknicz1, B Guba´n1, BS Bolla1, K Buza´s2, M Harmati2, A´ Ba´lind2, P Horva´th2, Z BataCso¨rgo¨1, L Keme´ny1 and I Ne´meth1 1 Dermatology and Allergology, University of Szeged, Szeged, Hungary and 2 Institute of Biochemistry, Biological Research Center, Szeged, Hungary Recently great attention is given to the role of tumor-stroma interactions mediated by melanoma-derived exosomes as well as to their interaction with peritumoral stromal cells for tumor supporting microenvironment. Therefore we aimed to investigate the effects of human melanoma-derived exosomes on peritumoral stromal cells and their role in spontaneous cell fusion, previously described by our research group. Exosomes were isolated by differential ultracentrifugation from the supernatant of UACC-257 human melanoma cell line. Human parental cells, including fibroblasts and adipose derived stem cells, were freshly isolated from normal human skin. Myofibroblasts were generated from fibroblasts after 10 days treatment with TGFb. For co-cultures we used UACC-257-GFP melanoma and fibroblast-RFP cell lines. Stromal cells and co-cultures were treated with exosomes at different dilutions (1x-10x-100x, respectively). Cell viability of the stromal cells was measured with xCELLigence System. Parental stromal cells were visualized by intravital membrane-labelling and immunocytochemistry. Co-cultures were digitalized by scanning microscope. Double positive cells were counted by Advanced Cell Classifier program after user-assisted intelligent computer learning. We observed increased cell impedance by xCELLigence, in line with it higher cell viability, proliferation and more confluent cell cultures in the exosome-treated parental fibroblasts, myofibroblasts and mesenchymal stem cells, respectively. SMA expression was increased in exosome-treated fibroblasts contrary to vimentin and desmin. Advanced Cell Classifier program did not show significantly increased spontaneous cell fusion rate in co-cultures. Based on our results melanoma-derived exosomes can influence normal stromal cells, since they affect their function, proliferation, and viability they may convert them into tumor promoting niche.
566
567
Elucidating the role of caveolin-2 in squamous cell carcinoma development A Overmiller1, J Pierluissi1, K McGuinn1, S Addya4, K Tsai2, J Wahl3 and MG Mahoney1,4 1 Dermatology & Cutaneous Biology, Thomas Jefferson University, Philadelphia, PA, 2 Tumor Biology, Moffit Cancer Center, Tampa, FL, 3 College of Dentistry, University of Nebraska Medical Center, Lincoln, NE and 4 Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA The pathogenesis of SCC of the skin requires pre-malignant alterations in the functional biology of keratinocytes. Caveolins (Cav1-3) are scaffolding proteins that serve as key structural components of the specialized membrane microdomains called caveolae. Caveolins and caveolae are involved in cellular functions including signal transduction by binding to and organizing receptors and signaling molecules. The role of Cav1 as a tumor suppressor is well documented, but the function of its binding partner Cav2, particularly in skin cancer, is unknown. We have demonstrated that the tumor promoter Dsg2 associates with and decreases the level of Cav1, modulates lipid raft dynamics, and activates EGFR by displacing it from membrane rafts. Here we sought to identify factors whose expression were modified by Dsg2 in the epidermis of mice by RNA microarray or SCC cells by RNA-Seq. Interestingly, Cav2 mRNA was downregulated in both systems by w2 fold and confirmed at the protein level. In the normal human epidermis, Cav2 was strongly detected in the basal cell layer. In SCCs, Cav2 was either lost or had generalized expression, suggesting a multifactorial role in tumorigenesis (N¼9 normal, 50 SCC). Interestingly, nuclear localization of Cav2 was detected in poorly differentiated tumors, possibly through a previously identified mechanism of binding to active Erk1/2. Indeed, activation of the MAPK pathway by EGF promoted nuclear localization of Cav2 in SCC cells. Finally, we established tumor xenografts by injecting SCC cells subcutaneously in SCID mice and demonstrated that Dsg2 overexpression downregulated Cav2 and enhanced tumor growth. Conversely, Dsg2-targeted mAbs decreased Dsg2 and EGFR, increased Cav2, and decreased tumor volume. This study elucidates the role of Cav2 in SCC development and offers a new pathway for therapeutic targeting.
Ultraviolet (UV)-A irradiation induces changes in metabolism which influence, via enhanced Warburg effect, melanoma invasion Y Kamenisch1, T Baban2, I Ivanova1, W Schuller2, G Metzler2, J Bauer2, C Garbe2, B Schittek2, M Ro¨cken2 and M Berneburg1 1 Dermatology, UKR, Regensburg, Germany and 2 Dermatology, Eberhard Karls University, Tu¨bingen, Germany Melanoma is a malignant tumor with high mortality for which exposure to ultraviolet (UV) A radiation is considered to be a risk factor. Especially UVA (320-400nm) radiation induces the formation of reactive oxygen species (ROS) which damage cellular molecules. It was recently shown that UVA radiation can induce murine melanoma, but the role of UVA in the progression of melanoma is not clear. During early progression of melanomas before metastasizing, most melanomas show initial proliferation of melanoma cells and a metabolic characteristic of most proliferating tumor cells is the preference of aerobic glycolysis instead of oxidative phosphorylation (Warburg effect). Here we investigated the role of UVA radiation in progression of melanoma, especially induction of progression markers, changes in metabolism and Warburg effect and invasive potential. Upon UVA radiation, initial melanoma cells show increased Warburg effect with increased glucose consumption and increased lactate production. With in vitro invasion assays we show, that lactate, which is produced via UVA enhanced Warburg effect, increases invasiveness of initial melanoma cells. This effect is mediated by reactive oxygen species which are induced by UVA radiation, as treatment with ROS scavengers impairs UVA induced lactate production and invasion. Furthermore transcription of tumor relevant matrix metalloproteinases and not TIMP1 is highly upregulated upon treatment with lactate. Therefore we could show in melanoma cells, derived from melanomas of early progression, that production of lactate, induced by UVA radiation, increases invasiveness of initial melanoma cells via expression of MMPs. Furthermore we found that UVA radiation also changes the consumption of other metabolites like tyrosine, glutamine, leucine, arginine, threonine and phenylalanine. This shows that not only metabolites of the Warburg effect, but also other metabolites are changed upon UVA radiation.
568
569
Investigation of the role of type VII collagen in the HIF1a induced pro-angiogenic pathway F Shams1, MA Krupiczojc1, S Alexander1, E Rashidghamat2, J McGrath2, M Caley1, EA O’Toole1 and CA Harwood1 1 Centre for Cutaneous Research, Barts and The London School of Medicine and Dentistry, Whitechapel, United Kingdom and 2 St. John’s Institute of Dermatology, Kings College London, London, United Kingdom Type VII collagen (Col7) is the main component of anchoring fibrils in the basement membrane of skin. Loss of function mutations in the COL7A1 gene lead to recessive dystrophic epidermolysis bullosa (RDEB) with severe congenital blistering, scarring and later development of aggressive squamous cell carcinomas (SCCs). A recent study from our group has shown an increase in angiogenesis with loss of Col7 in RDEB. One of the main regulators of tumour angiogenesis is hypoxia. The most important regulator of the cellular response to hypoxia is the transcription factor HIF-1 and its subunit HIF-1a. In this study, we investigated the effect of hypoxia on SCC cell lines with loss of Col7 on HIF-1a, VEGFR1 and other angiogenic factors. SCC cells with stable knock down (KD) of Col7 established using lentiviral shRNA were grown in normoxia (20% oxygen) or hypoxia (0.2% oxygen). RNA and protein lysates were prepared and analysed using RT-PCR and western blotting. Findings were confirmed in vivo in mouse xenograft tumours generated using Col7 knockdown cells. Increased HIF-1a mRNA and protein expression were observed with knock down of Col7 (shCol7) compared to control (shC). Global expression profiling identified a number of angiogenesis related genes differentially regulated with loss of Col7 that were further investigated. Increased expression of VEGFR1, Amphiregulin, UPA and Ephrin A1 were all observed with loss of Col7. These changes were amplified by hypoxia and could be reversed in vivo by treatment with human recombinant Col7 (hrCol7). These data demonstrate that loss of Col7 enhances hypoxic signals and the expression of pro-angiogenic factors which are reversed by hrCol7. This work improves our understanding of angiogenesis in RDEB and could lead to new therapeutic strategies for RDEB wounds and SCC targeting angiogenic pathways and the adaptive hypoxic response activated by loss of Col7.
Lipidomic Biomarkers for Melanoma A Perez-Valle1, J Garate2, R Fernandez2, S Lage1, E Astigarraga3, G Barreda-Gomez3, J Ferna´ndez2, A Asumendi1, B Ochoa4 and M Boyano1 1 Cell biology and Histology, University of the Basque Country, Vitoria-Gasteiz, Spain, 2 Physical Chemistry, University of the Basque Country, Leioa, Spain, 3 IMG Pharma Biotech, Derio, Spain and 4 Physiology, University of the Basque Country, Leioa, Spain Several evidences suggest that not only the composition and quantity of some lipids are modified in cancer but also their metabolism. Moreover, these alterations may drive the malignification from melanocytes to melanoma. Therefore, the aim of this research was to study and compare the lipidome of melanoma, nevus and non-pathological melanocytes, in order to find new lipidomic biomarkers which will help in the diagnosis, prognosis and therapy election in melanoma. For this purpose, we studied the lipidome of 27 different cell lines: 3 skin melanocytes, 9 melanocytes isolated from nevi, 6 primary melanomas and 9 metastatic melanomas, using two different methodologies. First, we obtained lipid extracts from each sample and we analyzed the lipid composition performing an Ultra High Performance Liquid Chromatography and a tandem mass spectrometry with electrospray ionization. Second, we isolated the membranes of each cell line, and we printed them forming membrane microarrays using a new methodology, which enables the maintenance of the lipid environment of the membranes. These microarrays were analyzed by a mass spectrometer using Matrix Assisted Laser Desorption Ionization (MALDI). In addition, we also analyzed 10 melanoma and nevus biopsies using the MALDI-Image mass spectrometry, which gives the spatial distribution of each lipid in the biopsy. Taking together all the results, we identified thousands of lipids of different subclasses, among which a set of them was significantly altered when comparing normal skin and melanoma in the three experimental processes. Therefore, we found a good methodological process which allowed us to find a panel of lipids that can act as lipidomic biomarkers in melanoma.
www.jidonline.org S289
565
Role of CC-chemokine Receptor 6 (CCR6) and CC Ligand 20 (CCL20) mediated immunosurveillance in malignant melanoma D Martin-Garcia, A Enk and A Lonsdorf Department of Dermatology, University Hospital Heidelberg, Heidelberg, Germany Chemokine ligand 20 (CCL20) expressed in the epidermis are a potent impetus for the recruitment of subsets of dendritic cells (DC), B-cells and memory T cells expressing chemokine receptor 6 (CCR6), its exclusive receptor. CCL20 and a corresponding CCR6expressing immune cell infiltrate have been detected in several malignancies, including melanoma. Yet, the functional contribution of the CCR6/CCL20 axis for the immune control of melanoma remains controversial. The characterization of CCR6-guided immune cell subsets and their functional contribution for the immune control of melanoma comprises the focus of this project. We evaluated the homeostatic and inducible secretion of CCL20 by different murine and human melanoma cutaneous cell lines by enzyme-linked Immunoabsorbent assay (ELISA). Both, murine (B16, Ret) and human (A375, C32) melanoma cell lines are capable of secreting CCL20 upon stimulation with pro-inflammatory cytokines (i.e. TNFa, IL-1a, IL-1b and TGF-b) in vitro. In order to determine the functional relevance of CCR6 on local tumor growth, B16 melanoma cells retrovirally transduced with a vector that constantly overexpresses CCL20 (B16-CCL20) were injected subcutaneously in wild type C57BL/6 (WT) and congenic CCR6eknockout (CCR6KO) mice. While animals in both groups developed local tumors, we observed a significantly reduced tumor growth in CCR6KO mice. By contrast, WT and CCR6KO control groups (injected with a B16 line that does not express CCL20) did not display differences in tumor growth rate. In vitro data excludes the possibility of an autocrine apoptotic pathway. While the precise mechanisms require further investigation, our results suggest that CCL20 interactions in the microenvironment of cutaneous melanoma may be an essential factor for local tumor growth. Current experimental approaches focus on the identification of the local immune infiltrate by means of Fluorescence activated cells shorting (FACS) and expression of CCR6 and CCL20 in cutaneous melanoma of both WT and CCR6KO mice by means of real-time PCR.
Effects of melanoma derived exosomes on peritumoral stromal cells T Buknicz1, B Guba´n1, BS Bolla1, K Buza´s2, M Harmati2, A´ Ba´lind2, P Horva´th2, Z BataCso¨rgo¨1, L Keme´ny1 and I Ne´meth1 1 Dermatology and Allergology, University of Szeged, Szeged, Hungary and 2 Institute of Biochemistry, Biological Research Center, Szeged, Hungary Recently great attention is given to the role of tumor-stroma interactions mediated by melanoma-derived exosomes as well as to their interaction with peritumoral stromal cells for tumor supporting microenvironment. Therefore we aimed to investigate the effects of human melanoma-derived exosomes on peritumoral stromal cells and their role in spontaneous cell fusion, previously described by our research group. Exosomes were isolated by differential ultracentrifugation from the supernatant of UACC-257 human melanoma cell line. Human parental cells, including fibroblasts and adipose derived stem cells, were freshly isolated from normal human skin. Myofibroblasts were generated from fibroblasts after 10 days treatment with TGFb. For co-cultures we used UACC-257-GFP melanoma and fibroblast-RFP cell lines. Stromal cells and co-cultures were treated with exosomes at different dilutions (1x-10x-100x, respectively). Cell viability of the stromal cells was measured with xCELLigence System. Parental stromal cells were visualized by intravital membrane-labelling and immunocytochemistry. Co-cultures were digitalized by scanning microscope. Double positive cells were counted by Advanced Cell Classifier program after user-assisted intelligent computer learning. We observed increased cell impedance by xCELLigence, in line with it higher cell viability, proliferation and more confluent cell cultures in the exosome-treated parental fibroblasts, myofibroblasts and mesenchymal stem cells, respectively. SMA expression was increased in exosome-treated fibroblasts contrary to vimentin and desmin. Advanced Cell Classifier program did not show significantly increased spontaneous cell fusion rate in co-cultures. Based on our results melanoma-derived exosomes can influence normal stromal cells, since they affect their function, proliferation, and viability they may convert them into tumor promoting niche.
566
567
Elucidating the role of caveolin-2 in squamous cell carcinoma development A Overmiller1, J Pierluissi1, K McGuinn1, S Addya4, K Tsai2, J Wahl3 and MG Mahoney1,4 1 Dermatology & Cutaneous Biology, Thomas Jefferson University, Philadelphia, PA, 2 Tumor Biology, Moffit Cancer Center, Tampa, FL, 3 College of Dentistry, University of Nebraska Medical Center, Lincoln, NE and 4 Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA The pathogenesis of SCC of the skin requires pre-malignant alterations in the functional biology of keratinocytes. Caveolins (Cav1-3) are scaffolding proteins that serve as key structural components of the specialized membrane microdomains called caveolae. Caveolins and caveolae are involved in cellular functions including signal transduction by binding to and organizing receptors and signaling molecules. The role of Cav1 as a tumor suppressor is well documented, but the function of its binding partner Cav2, particularly in skin cancer, is unknown. We have demonstrated that the tumor promoter Dsg2 associates with and decreases the level of Cav1, modulates lipid raft dynamics, and activates EGFR by displacing it from membrane rafts. Here we sought to identify factors whose expression were modified by Dsg2 in the epidermis of mice by RNA microarray or SCC cells by RNA-Seq. Interestingly, Cav2 mRNA was downregulated in both systems by w2 fold and confirmed at the protein level. In the normal human epidermis, Cav2 was strongly detected in the basal cell layer. In SCCs, Cav2 was either lost or had generalized expression, suggesting a multifactorial role in tumorigenesis (N¼9 normal, 50 SCC). Interestingly, nuclear localization of Cav2 was detected in poorly differentiated tumors, possibly through a previously identified mechanism of binding to active Erk1/2. Indeed, activation of the MAPK pathway by EGF promoted nuclear localization of Cav2 in SCC cells. Finally, we established tumor xenografts by injecting SCC cells subcutaneously in SCID mice and demonstrated that Dsg2 overexpression downregulated Cav2 and enhanced tumor growth. Conversely, Dsg2-targeted mAbs decreased Dsg2 and EGFR, increased Cav2, and decreased tumor volume. This study elucidates the role of Cav2 in SCC development and offers a new pathway for therapeutic targeting.
Ultraviolet (UV)-A irradiation induces changes in metabolism which influence, via enhanced Warburg effect, melanoma invasion Y Kamenisch1, T Baban2, I Ivanova1, W Schuller2, G Metzler2, J Bauer2, C Garbe2, B Schittek2, M Ro¨cken2 and M Berneburg1 1 Dermatology, UKR, Regensburg, Germany and 2 Dermatology, Eberhard Karls University, Tu¨bingen, Germany Melanoma is a malignant tumor with high mortality for which exposure to ultraviolet (UV) A radiation is considered to be a risk factor. Especially UVA (320-400nm) radiation induces the formation of reactive oxygen species (ROS) which damage cellular molecules. It was recently shown that UVA radiation can induce murine melanoma, but the role of UVA in the progression of melanoma is not clear. During early progression of melanomas before metastasizing, most melanomas show initial proliferation of melanoma cells and a metabolic characteristic of most proliferating tumor cells is the preference of aerobic glycolysis instead of oxidative phosphorylation (Warburg effect). Here we investigated the role of UVA radiation in progression of melanoma, especially induction of progression markers, changes in metabolism and Warburg effect and invasive potential. Upon UVA radiation, initial melanoma cells show increased Warburg effect with increased glucose consumption and increased lactate production. With in vitro invasion assays we show, that lactate, which is produced via UVA enhanced Warburg effect, increases invasiveness of initial melanoma cells. This effect is mediated by reactive oxygen species which are induced by UVA radiation, as treatment with ROS scavengers impairs UVA induced lactate production and invasion. Furthermore transcription of tumor relevant matrix metalloproteinases and not TIMP1 is highly upregulated upon treatment with lactate. Therefore we could show in melanoma cells, derived from melanomas of early progression, that production of lactate, induced by UVA radiation, increases invasiveness of initial melanoma cells via expression of MMPs. Furthermore we found that UVA radiation also changes the consumption of other metabolites like tyrosine, glutamine, leucine, arginine, threonine and phenylalanine. This shows that not only metabolites of the Warburg effect, but also other metabolites are changed upon UVA radiation.
568
569
Investigation of the role of type VII collagen in the HIF1a induced pro-angiogenic pathway F Shams1, MA Krupiczojc1, S Alexander1, E Rashidghamat2, J McGrath2, M Caley1, EA O’Toole1 and CA Harwood1 1 Centre for Cutaneous Research, Barts and The London School of Medicine and Dentistry, Whitechapel, United Kingdom and 2 St. John’s Institute of Dermatology, Kings College London, London, United Kingdom Type VII collagen (Col7) is the main component of anchoring fibrils in the basement membrane of skin. Loss of function mutations in the COL7A1 gene lead to recessive dystrophic epidermolysis bullosa (RDEB) with severe congenital blistering, scarring and later development of aggressive squamous cell carcinomas (SCCs). A recent study from our group has shown an increase in angiogenesis with loss of Col7 in RDEB. One of the main regulators of tumour angiogenesis is hypoxia. The most important regulator of the cellular response to hypoxia is the transcription factor HIF-1 and its subunit HIF-1a. In this study, we investigated the effect of hypoxia on SCC cell lines with loss of Col7 on HIF-1a, VEGFR1 and other angiogenic factors. SCC cells with stable knock down (KD) of Col7 established using lentiviral shRNA were grown in normoxia (20% oxygen) or hypoxia (0.2% oxygen). RNA and protein lysates were prepared and analysed using RT-PCR and western blotting. Findings were confirmed in vivo in mouse xenograft tumours generated using Col7 knockdown cells. Increased HIF-1a mRNA and protein expression were observed with knock down of Col7 (shCol7) compared to control (shC). Global expression profiling identified a number of angiogenesis related genes differentially regulated with loss of Col7 that were further investigated. Increased expression of VEGFR1, Amphiregulin, UPA and Ephrin A1 were all observed with loss of Col7. These changes were amplified by hypoxia and could be reversed in vivo by treatment with human recombinant Col7 (hrCol7). These data demonstrate that loss of Col7 enhances hypoxic signals and the expression of pro-angiogenic factors which are reversed by hrCol7. This work improves our understanding of angiogenesis in RDEB and could lead to new therapeutic strategies for RDEB wounds and SCC targeting angiogenic pathways and the adaptive hypoxic response activated by loss of Col7.
Lipidomic Biomarkers for Melanoma A Perez-Valle1, J Garate2, R Fernandez2, S Lage1, E Astigarraga3, G Barreda-Gomez3, J Ferna´ndez2, A Asumendi1, B Ochoa4 and M Boyano1 1 Cell biology and Histology, University of the Basque Country, Vitoria-Gasteiz, Spain, 2 Physical Chemistry, University of the Basque Country, Leioa, Spain, 3 IMG Pharma Biotech, Derio, Spain and 4 Physiology, University of the Basque Country, Leioa, Spain Several evidences suggest that not only the composition and quantity of some lipids are modified in cancer but also their metabolism. Moreover, these alterations may drive the malignification from melanocytes to melanoma. Therefore, the aim of this research was to study and compare the lipidome of melanoma, nevus and non-pathological melanocytes, in order to find new lipidomic biomarkers which will help in the diagnosis, prognosis and therapy election in melanoma. For this purpose, we studied the lipidome of 27 different cell lines: 3 skin melanocytes, 9 melanocytes isolated from nevi, 6 primary melanomas and 9 metastatic melanomas, using two different methodologies. First, we obtained lipid extracts from each sample and we analyzed the lipid composition performing an Ultra High Performance Liquid Chromatography and a tandem mass spectrometry with electrospray ionization. Second, we isolated the membranes of each cell line, and we printed them forming membrane microarrays using a new methodology, which enables the maintenance of the lipid environment of the membranes. These microarrays were analyzed by a mass spectrometer using Matrix Assisted Laser Desorption Ionization (MALDI). In addition, we also analyzed 10 melanoma and nevus biopsies using the MALDI-Image mass spectrometry, which gives the spatial distribution of each lipid in the biopsy. Taking together all the results, we identified thousands of lipids of different subclasses, among which a set of them was significantly altered when comparing normal skin and melanoma in the three experimental processes. Therefore, we found a good methodological process which allowed us to find a panel of lipids that can act as lipidomic biomarkers in melanoma.
www.jidonline.org S289