[Relationship between genetic polymorphism of promoter region let-7 and genetic susceptibility to hepatocellular carcinoma].

OBJECTIVE

The purpose of this study was to discuss the relationship between genetic polymorphism of promoter region let-7 and genetic susceptibility to hepatocellular carcinoma (HCC) in Chinese population.

METHODS

In this case-control study, 1300 cases of HBV positive patients were recruited in case group and another 1344 cases of persistent chronic HBV carriers were selected as control. 5 ml of blood sample was collected from each subject, from which the DNA was extracted; and rs10877887 and rs13293512 in promoter region let-7 were selected as the study sites. The polymorphism was detected by TaqMan allelic discrimination assay and the OR value (95%CI) was evaluated by Logistic Regression Method to analyze the relationship between susceptibility to HCC and different genotypes.

RESULTS

The frequencies of genotype TT, CT and CC in site rs10877887 were 43.0% (542/1261), 44.7% (564/1261) and 12.3% (155/1261) respectively in case group; while separately 44.0% (581/1319), 44.4% (585/1319) and 11.6% (153/1319)in control group. The frequencies of genotype TT, CT and CC in site rs13293512 were 32.0% (406/1270), 48.1% (611/1270) and 19.9% (253/1270) respectively in case group; while separately 33.1% (427/1291), 49.4% (638/1291) and 17.5% (226/1291) in control group. The results of multifactor logistic regression analysis showed no statistical significance in the relationship between different genotype TT, mutated genotype C in site rs10877887 and susceptibility to HCC (CC + CT vs TT, adjusted OR = 1.05, 95%CI: 0.90 - 1.23); and either no statistical significance in the relationship between different genotype TT, mutated genotype C in site rs13293512 and susceptibility to HCC (CC + CT vs TT, adjusted OR = 1.06, 95%CI: 0.89 - 1.25). The united-analysis of the two sites showed the frequencies of 0, 1, 2 and 3-4 mutated-genotype C were 13.3% (164/1235), 36.2% (447/1235), 33.0% (408/1235) and 17.5% (216/1235) respectively in case group; and separately 14.2% (181/1269), 37.0% (469/1269), 33.1% (420/1269) and 15.7% (199/1269) in control group. The susceptibility to HCC in 1,2,3-4 mutated-genotype C carriers were 1.05 (0.81 - 1.34), 1.07 (0.83 - 1.38) and 1.22 (0.91 - 1.62) times of the non-mutated genotype subjects; but there was no statistical significance (Wald χ(2) = 1.79, P = 0.181).

CONCLUSION

The polymorphism of study sites rs10877887 and rs13293512 may not be the biomarker of susceptibility to HCC in Chinese.