Genetic polymorphisms of TERT and CLPTM1L and risk of lung cancer--a case-control study in a Chinese population

Background/objectives: Genetic variants of telomerase reverse transcriptase (TERT) and cleft lip and palate trans-membrane 1 like (CLPTM1L) genes in chromosome 5p15.33 region were previously identified to influence the susceptibility to lung cancer. We examined the association of single nucleotide polymorphisms (SNPs) in TERT and CLPTM1L genes with lung cancer and explored their potential modifying effects on the relationship between environmental risk factors and lung cancer in a Chinese population.

Methods: We genotyped rs2736100 (TERT) and rs401681 (CLPTM1L) SNPs in a case-control study with 399 lung cancer cases and 466 controls form Taiyuan, China. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression models. Potential confounders were controlled for in the adjusted models.

Results: We found that the GG genotype of TERT was positively associated with lung cancer (OR=1.47, 95% CI: 1.00-2.16). The association was stronger in participants older than 60years, exposed to low indoor air pollution and adenocarcinoma and squamous cell carcinoma (SCC) in recessive model analysis. The GA genotype of CLPTM1L was inversely associated with lung cancer (OR=0.72, 95% CI: 0.54-0.97). The association was stronger in participants 60 years old or younger, males, heavy smokers, exposed to low indoor air pollution and SCC in dominant model analysis. Individuals carrying both TERT and CLPTM1L risk genotypes had higher risk of lung cancer (OR=1.80, 95% CI: 1.15-2.82). Significant interaction was observed between CLPTM1L and indoor air pollution in association with lung cancer.

Conclusions: Our results reiterate that genetic variants of TERT and CLPTM1L contribute to lung cancer susceptibility in Chinese population. These associations need to be verified in larger and different populations.