Analysis of Cyclin D1 G870A Polymorphism in Patients with Head and Neck Cancers

Objective: Head and neck cancer (HNC) is the sixth leading cancer among the most frequent cancers worldwide. Studies indicate that genetic predisposition plays an important role for HNC risk and a polymorphism in cyclin D1 (CCND1) gene taking part in regulation of cell cycle is considered to be the underlying cause of genetic predisposition. A few studies are available in literature on CCND1 gene polymorphism in HNC. No studies are available in literature investigating this polymorphism in Turkish HNC patients. In our study, G870A polymorphism in CCND1 gene was analysed and the relationship between allele and genotype distributions and clinical parameters was evaluated. Material and Methods: Peripheral blood samples of 95 HNC patients and 40 healthy controls were analysed as part of the study. CCND1 gene-specific polymorphic region was reproduced with polymerase chain reaction after DNA was obtained from the collected samples, afterwards it was cut using a proper restriction enzyme and results were assessed with video-gel documentation system. Polymorphic distributions were compared with allele frequencies of healthy individuals using Finetti case-control statistical program and relationships with clinical and pathologic findings of the patients were analysed using chi(2) (Chi-square) tests. Results: While a significant difference was not found between head and neck cancer patients and control group in terms of allele and genotype distributions, GA heterozygot genotype and combined GA + AA genotypes were found associated with low disease risk in patient with non-squamous cell cancer (NSCC). Additionally, A allele was detected significantly frequent in SCC group compared to NCCC patients. Conclusion: Different variants of CCND1 gene are considered to be effective in head and neck carcinogenesis according to tumor histology