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P3.69. Cytokeratins as prognostic markers in oral cancer
Poster Abstracts Oral AbstractsPoster ListOrals ListPan. Disc. & Symp. Abs.Keynote Abs.Keynote Bios.ProgramIAOOWelcomeCommittee Listings
224
Poster session III et al. / Oral Oncology Supplement 3 (2009) 201–236
Stat3: A risk predictor in oral carcinogenesis. doi:10.1016/j.oos.2009.06.593
P3.68. Cancer stem cells as mediators of treatment resistance in squamous cell carcinoma of the head and neck A. Okamoto a,*, K. Chikamatsu a, K. Sakakura b, K. Hatsushika b, G. Takahashi a, K. Masuyama a a b
University of Yamanashi, Japan University of Pittsburgh Cancer Institute, United States
Squamous cell carcinoma of the head and neck (SCCHN) contains a heterogenous population of cancer cells. Evidence has accumulated indicating that only a minority of cancer cells with stem cell properties, cancer stem cells (CSCs), is responsible for initiating, maintaining, and expanding the tumor growth. CD44 is currently used to identify CSCs as one of the cell surface markers for SCCHN. In this study, we investigated the identification, expansion, and characterization of CD44+ cancer stem-like cells from a SCCHN cell line. Under serum-free medium culture conditions, we enriched a subpopulation of CD44+ cells that possesses a marked capacity for forming tumor spheres, proliferation, migration, and invasion in vitro. Furthermore, the CD44+ cell population that had been purified using immunomagnetic beads was significantly more resistant to various chemotherapeutic agents including carboplatin, docetaxel, paclitaxel, 5-FU, and cisplatin than the CD44 cell population. Gene expression analysis demonstrated that CD44+ cells expressed a higher level of ABCB1, ABCG2, CYP2C8, and TERT than CD44 cells. Moreover, the CD44+ cell population was also resistant to apoptosis induced by other proapoptotic stimuli. Thus, various molecular mechanisms appear to be involved in the treatment resistance of CD44+ cells. Our findings suggest that the presence of such CSCs with the potential to survive conventional treatment regimens has important clinical implications for head and neck cancer treatment. Further study of CSCs in SCCHN may facilitate the development of novel therapies against this devastating disease. doi:10.1016/j.oos.2009.06.594
P3.69. Cytokeratins as prognostic markers in oral cancer D. Chaukar a,*, P. Pai a, M. Vaidya b, P. Chaturvedi a, V. Sawant b, A. Dcruz a a
Tata Memorial Hospital, India Advanced Centre for Treatment, Research and Education in Cancer, India b
Introduction: The search for prognostic factors in oral cancers is ongoing. Intermediate filaments (IFs) have proved to be valuable markers because of their high order of cell and tissue specificity. We present a Prospective study to define the expression pattern of cytokeratin 1, 5,8,18 and Vimentin in squamous cell carcinoma of oral cavity, cut margins, surrounding normal mucosa and correlate the expression patterns with clinical parameters. Methods: Study included 48 patients who underwent surgery with neck dissection between 2003–2004. Immunohistochemistry was done on formalin fixed, paraffin embedded sections by using monoclonal antibodies specific for CK 1, 5, 8, 18 and vimentin. Results: Tumor showed aberrant expression of CK1 in 30%, CK8 in 54%, CK18 in 44% and vimentin in 85%. CK5 non expression seen in
29%. In patients with tumor expressing 8, 18 and vimentin, 57% were poorly, 36% moderately, and 7% well differentiated. 43% showed nodal involvement when all 3 markers were positive and 36% of patients developed recurrence. In cut margins, When 8, 18 were not expressed with CK5 expression, 13% developed recurrence as compared to 33% when they were expressed. CK18 was expressed in 35% of the cut margins specimen of which 53% developed recurrence (8 pts). CK 5 expression was seen in all patients with recurrence. In patients who developed recurrence within 6 months, cut margins showed CK 8 or 18 expressions with Vimentin in 88% (7/8) patients. Conclusions: Cytokeratin 8, 18 and vimentin expression patterns exhibit definite relationship with oral cancers. CK18 expression in cut margins is reliable marker to predict recurrence. Vimentin, although a diagnostic tool, had limited value as a prognostic indicator. CK 5 aberrant expression was seen in all patients with recurrence. The aberrant expression of keratin like CK 8 and 18 seems to have a greater prognostic value than the non expression of CK5. doi:10.1016/j.oos.2009.06.595
P3.70. Transforming growth factor beta-1 (TGF beta-1) polymorphisms are infrequent but exist in selected loci in oral submucous fibrosis R. Rajendran *, R.K. Harish, P. Vidhyadharan, S. Anil, M. Banerjee College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia Aim: Oral submucous fibrosis (OSF) is a potent precancerous condition of the oral mucosa, assuming epidemicproportions in the Indian subcontinent. The nature of this disease remains enigmatic and the pathogenesis remains obscure. An attempt is made here to investigate the role of transforming growth factor beta-1 gene polymorphism inthe pathogenesis of oral submucous fibrosis. Materials and methods: The current study included 24 patients withoral submucous fibrosis and 24 healthy controls. Seven polymorphisms in TGFb 1 gene were selected for the study.They include three polymorphisms [Arg25Pro, Leu10Pro, and Glu47Gly] in exon 1, two polymorphisms (G-800A and C-509T) in promoter region and two polymorphisms in 50 UTR region (rs13306708 (C > T)andrs9282871(G > A)). Blood samples were collected from the patients as well as controls and DNA was isolated from it. Specificprimers were used for amplifying the target regions and following it sequencing was performed. The polymorphisms were analysed by checking the sequenced data using BioeditÒ software. Results: The significance of thepolymorphisms was analysed using Hardy Weinberg equilibrium. A p value less than 0.05 is considered to besignificant. There was no statistically significant difference in the genotypic or allelic frequency distributionsbetween patient and control group in all the three polymorphisms of exon 1, two polymorphisms of promoter regionand one polymorphism (rs9282871) in 50 UTR region. But a p value of 0.03 was obtained for the C to T polymorphism (rs13306708) in 50 UTR region and hence it can be considered to be significant. The role of thispolymorphism in the pathogenesis of oral submucous fibrosis is discussed. Conclusion: The polymorphism in 50 UTR C–T in TGF b1 gene has a significant association with OSF, being a prime determinant in the pro-angiogenicpathway which has got direct bearing with the pathophysiology of the disease. The proximity of this polymorphism to the transcription binding site and the associated risk factor is discussed. doi:10.1016/j.oos.2009.06.596
224
Poster session III et al. / Oral Oncology Supplement 3 (2009) 201–236
Stat3: A risk predictor in oral carcinogenesis. doi:10.1016/j.oos.2009.06.593
P3.68. Cancer stem cells as mediators of treatment resistance in squamous cell carcinoma of the head and neck A. Okamoto a,*, K. Chikamatsu a, K. Sakakura b, K. Hatsushika b, G. Takahashi a, K. Masuyama a a b
University of Yamanashi, Japan University of Pittsburgh Cancer Institute, United States
Squamous cell carcinoma of the head and neck (SCCHN) contains a heterogenous population of cancer cells. Evidence has accumulated indicating that only a minority of cancer cells with stem cell properties, cancer stem cells (CSCs), is responsible for initiating, maintaining, and expanding the tumor growth. CD44 is currently used to identify CSCs as one of the cell surface markers for SCCHN. In this study, we investigated the identification, expansion, and characterization of CD44+ cancer stem-like cells from a SCCHN cell line. Under serum-free medium culture conditions, we enriched a subpopulation of CD44+ cells that possesses a marked capacity for forming tumor spheres, proliferation, migration, and invasion in vitro. Furthermore, the CD44+ cell population that had been purified using immunomagnetic beads was significantly more resistant to various chemotherapeutic agents including carboplatin, docetaxel, paclitaxel, 5-FU, and cisplatin than the CD44 cell population. Gene expression analysis demonstrated that CD44+ cells expressed a higher level of ABCB1, ABCG2, CYP2C8, and TERT than CD44 cells. Moreover, the CD44+ cell population was also resistant to apoptosis induced by other proapoptotic stimuli. Thus, various molecular mechanisms appear to be involved in the treatment resistance of CD44+ cells. Our findings suggest that the presence of such CSCs with the potential to survive conventional treatment regimens has important clinical implications for head and neck cancer treatment. Further study of CSCs in SCCHN may facilitate the development of novel therapies against this devastating disease. doi:10.1016/j.oos.2009.06.594
P3.69. Cytokeratins as prognostic markers in oral cancer D. Chaukar a,*, P. Pai a, M. Vaidya b, P. Chaturvedi a, V. Sawant b, A. Dcruz a a
Tata Memorial Hospital, India Advanced Centre for Treatment, Research and Education in Cancer, India b
Introduction: The search for prognostic factors in oral cancers is ongoing. Intermediate filaments (IFs) have proved to be valuable markers because of their high order of cell and tissue specificity. We present a Prospective study to define the expression pattern of cytokeratin 1, 5,8,18 and Vimentin in squamous cell carcinoma of oral cavity, cut margins, surrounding normal mucosa and correlate the expression patterns with clinical parameters. Methods: Study included 48 patients who underwent surgery with neck dissection between 2003–2004. Immunohistochemistry was done on formalin fixed, paraffin embedded sections by using monoclonal antibodies specific for CK 1, 5, 8, 18 and vimentin. Results: Tumor showed aberrant expression of CK1 in 30%, CK8 in 54%, CK18 in 44% and vimentin in 85%. CK5 non expression seen in
29%. In patients with tumor expressing 8, 18 and vimentin, 57% were poorly, 36% moderately, and 7% well differentiated. 43% showed nodal involvement when all 3 markers were positive and 36% of patients developed recurrence. In cut margins, When 8, 18 were not expressed with CK5 expression, 13% developed recurrence as compared to 33% when they were expressed. CK18 was expressed in 35% of the cut margins specimen of which 53% developed recurrence (8 pts). CK 5 expression was seen in all patients with recurrence. In patients who developed recurrence within 6 months, cut margins showed CK 8 or 18 expressions with Vimentin in 88% (7/8) patients. Conclusions: Cytokeratin 8, 18 and vimentin expression patterns exhibit definite relationship with oral cancers. CK18 expression in cut margins is reliable marker to predict recurrence. Vimentin, although a diagnostic tool, had limited value as a prognostic indicator. CK 5 aberrant expression was seen in all patients with recurrence. The aberrant expression of keratin like CK 8 and 18 seems to have a greater prognostic value than the non expression of CK5. doi:10.1016/j.oos.2009.06.595
P3.70. Transforming growth factor beta-1 (TGF beta-1) polymorphisms are infrequent but exist in selected loci in oral submucous fibrosis R. Rajendran *, R.K. Harish, P. Vidhyadharan, S. Anil, M. Banerjee College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia Aim: Oral submucous fibrosis (OSF) is a potent precancerous condition of the oral mucosa, assuming epidemicproportions in the Indian subcontinent. The nature of this disease remains enigmatic and the pathogenesis remains obscure. An attempt is made here to investigate the role of transforming growth factor beta-1 gene polymorphism inthe pathogenesis of oral submucous fibrosis. Materials and methods: The current study included 24 patients withoral submucous fibrosis and 24 healthy controls. Seven polymorphisms in TGFb 1 gene were selected for the study.They include three polymorphisms [Arg25Pro, Leu10Pro, and Glu47Gly] in exon 1, two polymorphisms (G-800A and C-509T) in promoter region and two polymorphisms in 50 UTR region (rs13306708 (C > T)andrs9282871(G > A)). Blood samples were collected from the patients as well as controls and DNA was isolated from it. Specificprimers were used for amplifying the target regions and following it sequencing was performed. The polymorphisms were analysed by checking the sequenced data using BioeditÒ software. Results: The significance of thepolymorphisms was analysed using Hardy Weinberg equilibrium. A p value less than 0.05 is considered to besignificant. There was no statistically significant difference in the genotypic or allelic frequency distributionsbetween patient and control group in all the three polymorphisms of exon 1, two polymorphisms of promoter regionand one polymorphism (rs9282871) in 50 UTR region. But a p value of 0.03 was obtained for the C to T polymorphism (rs13306708) in 50 UTR region and hence it can be considered to be significant. The role of thispolymorphism in the pathogenesis of oral submucous fibrosis is discussed. Conclusion: The polymorphism in 50 UTR C–T in TGF b1 gene has a significant association with OSF, being a prime determinant in the pro-angiogenicpathway which has got direct bearing with the pathophysiology of the disease. The proximity of this polymorphism to the transcription binding site and the associated risk factor is discussed. doi:10.1016/j.oos.2009.06.596