Background: Nonsmall cell lung cancer (NSCLC) mainly contains adenocarcinoma (AC) and squamous cell carcinoma (SqCC). This study investigated single nucleotide polymorphism (SNP) of topoisomerase II alpha (TOP2A) and dual-specificity phosphatase 6 (DUSP6) in a hospital-based case and control cohort of individuals for association with risk of different histological subtypes of NSCLC.
Materials and methods: A total of 454 (237 SqCC and 217 AC) NSCLC patients, and 454 healthy controls were recruited for analysis of TOP2A rs471692 and DUSP6 rs2279574 genotypes using the TaqMan polymerase chain reaction technique.
Results: TOP2A rs471692 and DUSP6 rs2279574 SNPs were in complete linkage disequilibrium; however, frequency of DUSP6 rs2279574 genotype was significantly different between the case and control, that is, DUSP6 rs2279574a/A and A/C genotypes might contribute to an increased risk of lung squamous carcinoma compared with the C/C genotype. Moreover, DUSP6 rs2279574 AA genotype was also significantly associated with advanced stages of lung cancer. In contrast, frequency of the TOP2A rs471692 genotype had no association between cases and controls (P = 0.906). Genotype frequency of DUSP6 rs2279574 was 11.9% for C/C, 43.6% for C/A, and 44.5% for A/A in the case versus 16.7% C/C, 43.4% C/A, and 39.9% A/A in the control population (χ2 = 3.136, P= 0.077 by Hardy-Weinberg equilibrium test [HWE]). The genotype frequency of TOP2A rs471692 was 50.0% for C/C, 41.6% for C/T, and 8.4% for T/T in the case versus 50.2% C/C, 43.0% C/T, and 6.8% T/T in the control populations (χ2 = 0.023, P= 0.879 by HWE test).
Conclusion: Individuals are carrying DUSP6 rs2279574 AA and AC genotypes associated with an increased risk in developing lung squamous carcinoma in Han Chinese and with advanced NSCLC stages.
Keywords: Dual specificity phosphatase 6; lung cancer; single nucleotide polymorphism; susceptibility; topoisomerase II alpha.