Interactions Between The Polymorphisms Of PTEN And Hepatitis B Virus Mutations In Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is an important malignant tumor in China, which is the first and second of the malignant tumor mortality in rural and urban. The occurrence of HCC is affected by many factors such as environment exposure, chronic virus infection and host genetic susceptibility. In China, chronic HBV infection is the major risk factor of HCC. The subjects with chronic hepatitis B virus in China account for one-third of that in the world, while HCC cases in this country account for more than50%of the world. In addition, the occurrence of HCC is associated with the HBV contributed liver chronic inflammation. But, the majority of patients with chronic HBV infection don’t develop into HCC, indicating that the genetic susceptibility of Chinese plays an important role in the development of HCC.PTEN (Phosphatase and tensin homologue deleted Chromosome10, PTEN) is the first tumor suppressor gene discovered by human that have double-Specificity to phosphatase. Otherwise, recent researches have indicated that the expression of HBX can regulate the transcriptional activation of PTEN and increase the phosphorylation of AKT. Thus, it can promote the growth and proliferation of tumor, and inhibit the apoptosis of tumor cell. HBX plays important roles in liver cancer. So, it makes great sense to study the interaction between PTEN polymorphisms and HBV mutations in the development of HCC.Objective:This study was aimed to investigate the associations of polymorphisms of PTEN (rs1234220, rs2299939and rs1234213) with the susceptibility of HCC, and then elucidate the interaction between polymorphisms of PTEN and HBV mutations associated with HCC in HBV-positive HCC. It was also aimed to reveal the viral and genetic risk factors of HCC. It would provide clues for the prevention of the risk factors of HCC and lay foundation on specific prophylaxis in China.Methods:Fluorescent probe-Real time quantitative PCR was used to identify the genotypes of three single nucleotide polymorphisms (SNPs) of PTEN gene. This study included1012healthy controls,316Asymptomatic HBsAg carriers (ASCs),316patients with CHB,316patients with LC and1021HCC cases. Hardy-Weinberg equilibrium test was performed on the internet (http://ihg.gsf.de/ihg/snps.htmn. SPSS16.0software was used to enter and analyse the data. Student’s t-test for independent samples, analysis of variance, Chi-square test, and unconditional logistic regression analysis were used to investigate the associations of polymorphisms of PTEN with chronic HBV infection or HCC, and its interaction with the HBV mutations in the development of HCC.Results:1. Associations of polymorphisms of PTEN with chronic HBV infection or HCC(1) Compared with healthy controls, rs1234220CT genotype and C (CT+CC) allele were significantly associated with increased risks of HCC (AOR=1.37,95%CI=1.08-1.73; AOR=1.35,95%CI=1.07-1.69). Rs1234220CT genotype and C (CT+CC) allele were significantly associated with increased risks of HCC (AOR=1.28,95%CI=1.02-1.61;AOR=1.27,1.01-1.57), rs2299939GT genotype and T (GT+TT) allele were significantly associated with reduced risks of HCC (AOR=0.75,95%CI=0.62-0.92; AOR=0.79,95%CI=0.65-0.96), as compared with HBV-related liver diseases without HCC, respectively. Compared with all subjects without HCC, rs1234220CT genotype and C (CT+CC) allele were significantly associated with increased risks of HCC (AOR=1.30,95%CI=1.08-1.56; AOR=1.29,95%CI=1.07-1.54), and rs2299939GT genotype was significantly associated with a reduced risk of HCC (AOR=0.84,95%CI=0.71-0.99).(2) After stratified by gender, we found that in males:Compared with healthy controls, rsl234220CT genotype and C (CT+CC) allele significantly increased risks of HCC (AOR=1.35,95%CI=1.04-1.75; AOR=1.33,95%CI=1.03-1.71). Rs1234220CT genotype and C (CT+CC) allele were significantly associated with increased risks of HCC (AOR=1.31,95%CI=1.01-1.70; AOR=1.30,95%CI=1.01-1.67), and rs2299939GT genotype and T (GT+TT) allele were significantly associated with reduced risks of HCC (AOR=0.72,95%CI=0.57-0.90; AOR=0.76,95%CI=0.62-0.95), as compared with HBV-related liver diseases without HCC, respectively. Compared with all subjects without HCC, rs1234220CT genotype and C (CT+CC) allele were significantly associated with increased risks of HCC (AOR=1.30,95%CI=1.06-1.60; AOR=1.29,95%C1=1.06-1.58), and rs2299939GT genotype was significantly associated with a reduced risk of HCC (AOR=0.81,95%CI=0.68-0.98).In females, there was no significant difference between healthy controls, HBV natural clearance, HBV-related liver diseases without HCC or all subjects without HCC and HCC for PTEN polymorphisms. (3) In all HBV infected subjects, rs2299939T (GT+TT) allele was significantly asscociated with high ALT (AOR=1.26,95%CI=1.01-1.57); rs2299939GT genotype and T (GT+TT) allele were significantly associated with high viral load (≥104copies/ml)(AOR=1.33,95%CI=1.06-1.67; AOR=1.29,95%CI=1.03-1.60). In males with HBV infection, rs2299939GT genotype and T (GT+TT) allele were significantly associated with high ALT (AOR=1.35,95%CI=1.04-1.75; AOR=1.36,95%CI=1.06-1.74) and also associated with high viral load (≥104copies/ml)(AOR=1.38,95%CI=1.07-1.78; AOR=1.29,95%CI=1.01-1.66). There was no significant association with chronic HBV infection.(4) After stratified by HBV genotypes, in HBV genotype B, compared with HBV-related liver diseases without HCC, rs1234220CT genotype and C (CT+CC) allele significantly increased risks of HCC (AOR=2.02,95%CI=1.14-3.59; AOR=2.02,95%CI=1.14-3.59). However, this result needs to be validated using more samples.(5) After stratified by HBeAg status, in the HBV-infected subjects with negative HBeAg, rs2299939GT genotype and T (GT+TT) allele were significantly associated with reduced risks of HCC (AOR=0.68,95%CI=0.53-0.87; AOR=0.72,95%CI=0.57-0.92), as compared with HBV-related liver diseases without HCC.2. Interactions between the polymorphisms of PTEN and HBV mutations or HBV genotypes(1) Interactions between the polymorphism of rs1234220and HBV mutationsrsl234220TT genotype and "wild-type" of A1762T/G1764A, A3054T or C3116T served as controls, respectively, after adjusted for age and gender, we found1762T/1764A was significantly associated with an increased risk of HCC (AOR=3.71,95%CI=2.69-5.11), the combined effects of rs1234220C (CT+CC) and1762T/1764A significantly increased the risks of HCC (AOR=2.44,95%CI=1.93-3.07). But there was no significant interation between the polymorphism of rs1234220and A1762T/G1764A, A3054T or C3116T. The same results were in males and females.(2) Interactions between the polymorphism of rs2299939and HBV mutationsrs2299939GG genotype and "wild-type" of A1762T/G1764A, A3054T or C3116T served as controls, respectively, after adjusted for age and gender, we found both1762T/1764A and3116T significantly associated with increased risks of HCC (AOR=3.55,95%CI=2.48-5.08; AOR=2.17,95%CI=1.42-3.32), the combined effects of rs2299939T (GT+TT) and1762T/1764A significantly increased the risks of HCC (AOR=1.70,95%CI=1.39-2.08). When rs2299939GG genotype and "wild-type" of A3054T were controls, we found rs2299939T (GT+TT) was significantly associated with a reduced risk of HCC (AOR=0.62,95%CI=0.44-0.87). However, no significant interaction was found between the polymorphism of rs2299939and A1762T/G1764A. There were significant interactions between the polymorphism of rs2299939and A3054T or C3116T respectively (AOR=2.41,95%CI=1.08-5.35; AOR=0.34,95%CI=0.18-0.66). There was significant interaction between the polymorphism of rs2299939and C3116T in males.(3) Interactions between the polymorphism of rs1234213and HBV mutationsrs1234213CC genotype and "wild-type" of A1762T/G1764A, A3054T or C3116T served as controls, respectively, after adjusted for age and gender, we found1762T/1764A was significantly associated with an increased risk of HCC (AOR=3.95,95%CI=2.23-7.01),3116T significantly associated with reduced risks of HCC (AOR=0.51,95%CI=0.27-0.97). However, there was no significant interaction between the polymorphism of rs1234213and A1762T/G1764A or A3054T, we found a significant interaction between the polymorphism of rsl234213and C3116T, which significantly associated with an increased risk of HCC (AOR=3.68,95%CI=1.74-7.76). There was significant interaction between the polymorphism of rsl234213and C3116T in males.(4) Interactions between the polymorphisms of PTEN and HBV genotypesHBV genotype B, rs1234220TT, rs2299939GG or rs1234213CC served as controls, respectively, after adjusted by age and gender, we found the combined effects between HBV genotype C and rsl234220C (CT+CC), rs2299939T (GT+TT) or rsl234213T (CT+TT) were significantly associated with increased risks of HCC (AOR=1.68,95%CI=1.38-2.05; AOR=1.32,95%CI=1.10-1.60; AOR=1.29,95%CI=1.01-1.66);rs1234220C (CT+CC) significantly increased risks of HCC (AOR=2.02,95%CI=1.14-3.59); When HBV genotype B and rs1234220TT or rs2299939GG were controls, we found HBV genotype C was significantly associated with increased risks of HCC respectively (AOR=2.37,95%CI=1.72-3.28; AOR=2.11,95%CI=1.47-3.01). However, there was no significant interaction between the polymorphisms of PTEN and HBV genotypes in the development of HCC. 4. Association of haplotype of PTEN with HCCThe haplotype frequcency of PTEN rs1234220C-rs2299939G-rs1234213T was significantly higher in HCC than in healthy controls (AOR=1.32,95%CI=1.06-1.63).Conclusions:1. rs1234220CT genotype and C (CT+CC) allele were significantly associated with increased risks of HCC, rs2299939GT genotype was significantly associated with reduced risks of HCC. The same results were in males. There was no significant association with chronic HBV infection.2. In HBV genotype B, rs1234220CT genotype and C (CT+CC) allele significantly increased the risks of HCC, but it needs to validate using larger sample size.3. In HBV-infected subjects with negative HBeAg, rs2299939GT genotype and T (GT+TT) allele significantly reduced the risks of HCC.4. There were significant interactions between the polymorphism of rs2299939and A3054T or C3116T in all HBV infected subjects. In males, there was significant interaction between the polymorphism of rs2299939and C3116T.5. A significant interaction was found between the polymorphism of rs1234213and C3116T in all HBV infected subjects or in males.