Aim: The cell cycle regulator cyclin D1 (CCND1) is a critical regulator of the G1/S phase transition and plays an important part in several tumor types. This study aimed at investigating the association of CCND1 with and examining the interaction among CCND1 genotype and individual smoking habit in nasopharyngeal carcinoma susceptibility.
Patients and methods: A total of 352 native Taiwanese consisting of 176 cases and 176 controls were enrolled in this hospital-based study, and CCND1 A870G (rs9344) and C1722G (rs678653) genotyping were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and partially verified by direct sequencing.
Results: The results showed that there were significant differences between nasopharyngeal carcinoma and control groups in the distribution of the genotypic (p=0.0222) and allelic (p=0.0322) frequencies in the CCND1 A870G genotype. Individuals who carried at least one G allele (GG or AG) had a 0.71-fold lower risk of developing nasopharyngeal carcinoma compared to those who had the AA genotype (95% confidence interval=0.53-0.96). In addition, there is an obvious joint effect of CCND1 A870G genotype with smoking habit on nasopharyngeal carcinoma susceptibility.
Conclusion: These findings support the conclusion that the cell cycle regulation may play a role in nasopharyngeal carcinoma development and that CCND1 A870G polymorphism maybe a useful biomarker for nasopharyngeal carcinoma progression.