Relationships Between Cell Pathyway Genes Polymorphisms And The Risk Of Hepatocellular Carcinoma

Background and Objective:Single nucleotide polymorphism (SNP) as the third generation of genetic markers, with the characteristics of stability and universality, is widely used in a variety of disease association studies. Cell cycle control genes play a key role in the control of cell cycle. The mutation of genes will cause the change of activity and lead to the occurrence of cancer. It was found that cell cycle signaling pathway genes such as P53, CHEK2 and P21are closely related with human tumors. But the relationship between the cell cycle signaling pathway genes polymorphism and the hereditary susceptibility of HCC (hepatocellular carcinoma) has not been deeply studied. This study was conducted to investigate the frequency distribution of the 12 cell cycle pathway genes 15 SNPs, the association between SNPs and the hereditary susceptibility of HCC and the interaction of gene-gene and gene- environment.Methods:Through the information biology and the existing literature, we finally selected functional SNPs. A hospital-based case-control study was conducted. We collected new HCC patients who were diagnosed by unified diagnostic criteria to be the case group and collected the non-tumor patients for the same period to be the control group. The HCC patients and controls were from the same area and frequency matched by the gender, age and nationality. The general demographic information, behavior factors, medical history and examination information of all the objects were collected by unified questionnaires. The genomic DNA was isolated from peripheral venous blood using the Phenol-Chloroform. The genotyping was performed using the MALDI-TOF-MS.Statistical analyses were performed using the SPSS 16.0 software, Haploview4.2 software and SHEsis. All statistics tests were two-sided. A P value <0.05 was considered to indicate statistical significance.Results:(1) Functional SNPs site conditionIn this study, we selected 15 functional SNPs from 12 cell cycle pathway genes (MCM4 rs2305952, YWHAB rs2425675, CDKN2A rs3088440, TGFB3 rs3917148, RBL2 rs3929, RAD21 rs6987652, SMAD3 rs11556090、rs8025774, KAT2B rs17006625、rs4858770, MCM7 rs2070215、rs2261360, CDKN1A rs3176320, CDC25C rs3734166, CHEK1 rs515255).(2) The General demographic characteristics and behavioral information of the subjectsThere were no significant differences between the HCC patients and the controls in terms of age, gender, and nationality (P>0.05), however, HCC patients had a significantly higher rate of a positive history of HBV infection, a family history of HCC, smoking, and alcohol consumption (P<0.001).(3) The results of SNPs genotypingIn this study, we genotyped 2327 samples, including 1127 case samples and 1200 control samples. Finally we chose 2157 samples including 1019 case samples and 1138 control samples after eliminating the samples which genotyped unclear or no call.(4) Allele frequencies and genotype distribution of the SNPsHardy-Weinberg equilibrium (HWE) was evaluated by a goodness-of-fit x2 test to compare the observed genotype frequencies with the expected ones. In the control group, of the 15 SNPs, all but rs3176320 were in line with the HWE. So the study finally explored the relationship between 14 SNPs polymorphisms and the risk of HCC.(5) Associations of genetic polymorphisms with the risk of HCCWe performed multivariable logistic regression after adjusting for age, gender, nationality, smoking, drinking, family history of HCC, and HBV infection. Compared with the genotype TT, MCM4 rs2305952 genotype CC individuals suffering from HCC risk is 0.22 times (P=0.01, OR=0.22, OR95%CI:0.08-0.63). Compared with the genotype CC, CHEK1 rs515255 genotype TC individuals suffering from HCC risk is 0.73 times (P=0.02, OR=0.73, OR95% CI:0.56-0.96). Compared with the genotype CC, CHEK1 rs515255 genotype TT individuals suffering from HCC risk is 0.67 times (P=0.04, OR=0.67, OR95%CI:0.46-0.97). Compared with the genotype CC, CHEK1 rs515255 genotype TC/TT individuals suffering from HCC risk is 0.72 times (PN).01, OR=0.72, OR95% CI:0.56-0.92). Compared with the genotype AA, KAT2B rs 17006625 genotype GG individuals suffering from HCC risk is 1.64 times (P=0.04, OR=1.64, OR95%CI:1.01-2.64).(6) Stratified analysisWe conducted a stratified analysis based on HBV infection, smoking, drinking alcohol. In the positive HBV infection, no-drinking, no-smoking subjects, MCM4 rs2305952 was associated with a significantly risk of HCC (P<0.05). In the negative HBV infection, no-drinking subjects, CHEK1 rs515255 was associated with a significantly risk of HCC (P<0.05).In the negative HBV infection subjects, KAT2B rs 17006625 was associated with a significantly risk of HCC (P<0.05).(7) Analysis on interaction of gene-gene and gene-environmentGene-gene interactions were found between rsl1556090 and rs2305952, between rs2425675 and rs3929, between rs17006625 and rs3088440, between rs3917148 and rs6987652, between rs3734166 and rs3917148, between rs17006625 and rs2070215 (P<0.05). gene-environment interaction were found between rs8025774 and HBV infection status (P<0.05)。(8) Haplotype analysisThe frequency of the haplotype SMAD (Crs8025774-Grs11556090) was different in HCC cases and control group (x2=M.88,P=0.03, OR=1.18,95%CI:1.02-1.37). The frequency of the haplotype MCM7 (Crs2261360-Grs2070215) was different in HCC cases and control group (x2=5.51,P=0.02, OR=1.17,95%CI:1.03-1.33).Conclusion:(1) The polymorphisms of MCM4 rs2305952, CHEK1 rs515255 and KAT2B rs17006625 may be associated with the risk of HCC.(2) The interactions between gene-gene and gene-environment may be associated with the risk of HCC.(3) Haplotype SMAD (CrS8O25774-Grs11556090) and haplotype MCM7 (Crs2261360-Grs2070215) may increase the risk of HCC.