Relationship Between Polymorphisms Of HLA And Susceptibility To Hepatitis B Virus Related Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), which leads to700,000dealths anually is one of thetop ten cancers released by WHO. China has a high incidence of HCC and accounts for55%of the world's newly diagnosed HCC cases. It is generally considered that theoccurrence of HCC was a stepwise course during which multi-factors and multi-genesco-functioned. Of these factors, chronic hepatitis B virus (HBV) infection is thepredominant risk factors for HCC. More than85%of HCC cases in China are positive forHBV, and chronic HBV infection and the related HCC have been heavy burden for publichealth. The factor that Chinese people have greater possibility to develop HCC after HBVinfection indicates that host genetic susceptibility plays an important role in thedevelopment of HCC.Human leucocyte antigen (HLA) is closely related to the immune response after HBVinfection, of which HLA-â…¡ genes play a key role in the presentation of antigens andimmune response. Some specific HLA may affect the chronification of HBV infection andintensity of immune response.Objectives: This study was to investigate the associations of polymorphisms ofHLA-DP (rs3077, rs3135021, rs2281388, and rs9277535) with chronic HBV infection andHBV related HCC, and then elucidate the interaction between polymorphisms of HLA-DPand HCC associated HBV mutations or HBV genotypes in the development of HCC. It wasalso aimed to provide clue for HCC susceptible alleles in the development of chronic HBVinfection and HCCMethods: Fluorescent probe-real-time quantitative PCR method was used to determinthe genotypes of four single nucleotide polymorphisms (SNPs) of HLA-DP from1012healthy subjects,316asymptomatic HBsAg carriers (ASCs),316patients with chronichepatitis B (CHB),358patients with liver cirrhosis (LC), and1021HCC patients.Multiplex PCR was used to genotype HBV from ASCs, CHB, LC, and HCC. The Hardy-Weinberg equilibrium test was performed on the internet (http://ihg. gsf. de/ihg/snps.html). SPSS16.0software was used to enter and analyse the data. Student's t-test forindependent samples, analysis of covariance, Chi-square test, and unconditional logisticregression analysis were used to investigate the associations of polymorphisms of HLA-DPwith chronic HBV infection or HCC, and elucidate the multiplicative interaractions between polymorphisms of HLA-DP and HBV mutations or HBV genotypes in thedevelopment of HCC.Results:1. Associations of polymorphisms of HLA-DPwith chronic HBV infection or HCCWhen the healthy subjects were treated as the control, C/T or T/T genotype or T allele(C/T+T/T) of rs3077significantly decreased the risks of HBV infection without HCC(odds ratio [OR]=0.57,95%confidence interval [CI]=0.47-0.68; OR=0.50,95%CI=0.37-0.67; OR=0.55,95%CI=0.46-0.66) and HBV related HCC (OR=0.60,95%CI=0.49-0.72;OR=0.40,95%CI=0.30-0.55; OR=0.55,95%CI=0.46-0.66), as compared with C/Cgenotype. G/A genotype or A allele (G/A+A/A) of rs3135021significantly decreased therisks of HBV infection without HCC (OR=0.74,95%CI=0.61-0.89; OR=0.74,95%CI=0.62-0.89) and HBV related HCC (OR=0.80,95%CI=0.66-0.96; OR=0.79,95%CI=0.66-0.94), as compared with G/G allele. C/T or T/T genotype or T allele (C/T+T/T) ofrs2281388significantly increased the risks of HBV infection without HCC (OR=1.50,95%CI=1.23-1.83; OR=2.19,95%CI=1.69-2.83; OR=1.67,95%CI=1.38-2.01) and HBVrelated HCC (OR=1.38,95%CI=1.13-1.68; OR=2.02,95%CI=1.57-2.61; OR=1.54,95%CI=1.28-1.85), as compared with C/C allele. G/A or AA genotype or A allele (G/A+A/A) ofrs9277535significantly decreased the risks of HBV infection without HCC (OR=0.70,95%CI=0.57-0.85; OR=0.39,95%CI=0.30-0.51; OR=0.60,95%CI=0.50-0.72) and HBVrelated HCC (OR=0.62,95%CI=0.51-0.76; OR=0.46,95%CI=0.36-0.60; OR=0.57,95%CI=0.48-0.69), as compared with G/G allele. However, when the HBV-infected subjectswithout HCC were treated as the control, no significant associations were found betweenpolymorphisms of HLA-DP and susceptibility to HCC.2. Associations of polymorphisms of HLA-DP with chronic HBV infection or HCCin different sex groupsWhen the study subjects were stratified by sex and male healthy subjects were treated asthe control, C/T or T/T genotype or T allele of rs3077significantly decreased the risks ofHBV infection without HCC (OR=0.54,95%CI=0.43-0.67; OR=0.47,95%CI=0.33-0.66;OR=0.52,95%CI=0.42-0.65) and HBV related HCC (OR=0.60,95%CI=0.49-0.72; OR=0.40,95%CI=0.30-0.55; OR=0.55,95%CI=0.46-0.66), as compared with C/C genotype.G/A or A/A genotype or A allele of rs3135021significantly decreased the risks of HBVinfection without HCC (OR=0.64,95%CI=0.51-0.80; OR=0.50,95%CI=0.30-0.82; OR= 0.62,95%CI=0.50-0.77) and HBV related HCC (OR=0.75,95%CI=0.61-0.92; OR=0.59,95%CI=0.38-0.92; OR=0.73,95%CI=0.59-0.88), as compared with G/G allele. C/T or T/Tgenotype or T allele of rs2281388significantly increased the risks of HBV infectionwithout HCC (OR=1.60,95%CI=1.26-2.03; OR=2.78,95%CI=2.04-3.81; OR=1.86,95%CI=1.49-2.32) and HBV related HCC (OR=1.47,95%CI=1.18-1.83; OR=2.53,95%CI=1.88-3.40; OR=1.70,95%CI=1.38-2.09), as compared with C/C allele. G/A or A/Agenotype or A allele of rs9277535significantly decreased the risks of HBV infectionwithout HCC (OR=0.70,95%CI=0.56-0.89; OR=0.35,95%CI=0.25-0.48; OR=0.59,95%CI=0.47-0.73) and HBV related HCC (OR=0.60,95%CI=0.48-0.74; OR=0.42,95%CI=0.31-0.55; OR=0.54,95%CI=0.44-0.66), as compared with G/G allele.When the female healthy subjects were treated as the control, female subjects with C/Tgenotype or T allele of rs3077had decreased risks of HBV infection without HCC(OR=0.64,95%CI=0.45-0.92; OR=0.64,95%CI=0.46-0.90), as compared with those withC/C genotype. Female subjects with A/A genotype or A allele of rs9277535had decreasedrisks of HBV infection without HCC (OR=0.52,95%CI=0.31-0.85; OR=0.64,95%CI=0.45-0.91). However, when the female healthy subjects or HBV-infected subjects withoutHCC were treated as the control separately, no significant associations were found betweenpolymorphisms of HLA-DP and susceptibility to HCC.3. Associations of polymorphisms of HLA-DP with HBV related HCC in differentHBV genotype groupsWhen the HBV-infected subjects were stratified by HBV genotypes, HBV-infectedsubjects without HCC were treated as the control to investigate the associations ofpolymorphisms of HLA-DP with HBV related HCC. TT genotype of rs3077wasassociated with a decreased risk of HCC in HBV genotype C (OR=0.60,95%CI=0.38-0.95), as compared with C/C genotype, meanwhile, A/A genotype of rs9277535wasassociated with an increased risk of HCC in HBV genotype C (OR=1.88,95%CI=1.26-2.80), as compared with G/G genotype. However, no significant associations werefound between polymorphisms of HLA-DP and susceptibility to HCC in HBV genotype B.4. Interactions between polymorphisms of HLA-DP and HBV mutations in thedevelopment of HCCWhen the combinations of C/C genotype of rs3077with wild-type of T1674C/G,A1762T/G1764A, or G1896A were termed as references, among the HBV-infected subjects carrying C/C genotype of rs3077, T1674C/G, A1762T/G1764A, or G1896Amutation significantly increased the risks of HCC (AOR=2.42,95%CI=1.49-3.93; AOR=4.12,95%CI=2.68-6.34; AOR=2.05,95%CI=1.36-3.09) after adjustment for age, sex,HBV genotypes, and HBeAg status. The combination of C/T genotype of rs3077with thementioned HBV mutations separately also significantly increased the risks of HCC (AOR=1.73,95%CI=1.31-2.29; AOR=2.02,95%CI=1.59-2.58; AOR=1.69,95%CI=1.32-2.15).When the combinations of G/G genotype of rs3135021with wild-type of T1674C/G,A1762T/G1764A, or G1896A were termed as references, among the HBV-infectedsubjects carrying G/G genotype of rs3135021, T1674C/G, A1762T/G1764A, or G1896Amutation significantly increased the risks of HCC (AOR=2.84,95%CI=1.81-4.46; AOR=5.08,95%CI=3.35-7.72; AOR=2.34,95%CI=1.59-3.45) after adjustment for age, sex,HBV genotypes, and HBeAg status. The combination of G/A genotype of rs3135021withthe mentioned HBV mutations separately also significantly increased the risks of HCC(AOR=1.71,95%CI=1.28-2.29; AOR=2.34,95%CI=1.82-3.00; AOR=1.71,95%CI=1.33-2.19). When the combinations of C/C genotype of rs2281388with wild-type of T1674C/G,A1762T/G1764A, or G1896A were termed as references, among the HBV-infectedsubjects carrying C/C genotype of rs2281388, T1674C/G, A1762T/G1764A, or G1896Amutation significantly increased the risks of HCC (AOR=2.72,95%CI=1.37-5.39;AOR=4.16,95%CI=2.19-7.81; AOR=2.53,95%CI=1.41-4.55) after adjustment for age,sex, HBV genotypes, and HBeAg status. The combination of C/T genotype of rs2281388with the mentioned HBV mutations separately also significantly increased the risks ofHCC (AOR=1.66,95%CI=1.27-2.19; AOR=2.11,95%CI=1.58-2.82; AOR=1.67,95%CI=1.31-2.14). When the combinations of G/G genotype of rs9277535with wild-type ofT1674C/G, A1762T/G1764A, or G1896A were termed as references, among theHBV-infected subjects carrying G/G genotype of rs9277535, T1674C/G, A1762T/G1764A,or G1896A mutation significantly increased the risks of HCC (AOR=2.53,95%CI=1.45-4.43ï¼›AOR=3.35,95%CI=2.09-5.38ï¼›AOR=3.12,95%CI=1.94-5.02) after adjustment forage, sex, HBV genotypes, and HBeAg status. The combination of A/A genotype ofrs9277535with A1762T/G1764Aalso significantly increased the risk of HCC (AOR=1.86,95%CI=1.30-2.67). However, no significant multiplicative interactions betweenpolymorphisms of HLA-DP and T1674C/G, A1762T/G1764A, or G1896Awere found.After stratified by HBV genotypes, the combinations of G/G genotype of rs9277535 with wild-type of T1674C/G, A1762T/G1764A, or G1896A were termed as references, thecombinations of A/A genotype of rs9277535with A1762T/G1764A or G1896A bothsignificantly increased the risks of HCC adjusted with age and sex (AOR=1.77,95%CI=1.25-2.49; AOR=1.28,95%CI=0.85-1.93). Moreover, rs9277535significantly interactedwith T1674C/G in the devlopment of HCC in genotype C (AOR=0.31,95%CI=0.10-0.97).5. Interactions between polymorphisms of HLA-DP and HBV genotypes in thedevelopment of HCCAmong the HBV-infected subjects carrying C/C genotype of rs3077, HBV genotype Csignificantly increased the risks of HCC after adjustment for age, sex, and HBeAg status(AOR=2.18,95%CI=1.51-3.15). The combination of C/T genotype of rs3077with HBVgenotype C also significantly increased the risks of HCC (AOR=1.48,95%CI=1.22-1.80).Among the HBV-infected subjects carrying G/G genotype of rs3135021, HBV genotype Csignificantly increased the risks of HCC after adjustment for age, sex, and HBeAg status(AOR=1.90,95%CI=1.33-2.70). The combination of G/A genotype of rs3135021withHBV genotype C also significantly increased the risks of HCC (AOR=1.49,95%CI=1.23-1.81). Among the HBV-infected subjects carrying C/C genotype of rs2281388, HBVgenotype C significantly increased the risks of HCC after adjustment for age, sex, andHBeAg status (AOR=3.05,95%CI=1.60-5.82), The combination of C/T genotype ofrs2281388with HBV genotype C also significantly increased the risks of HCC (AOR=1.74,95%CI=1.28-2.37). Among the HBV-infected subjects carrying G/G genotype ofrs9277535, HBV genotype C significantly increased the risks of HCC after adjustment forage, sex, and HBeAg status (AOR=2.17,95%CI=1.43-3.28), The combination of G/Agenotype of rs9277535with HBV genotype C also significantly increased the risks of HCC(AOR=1.32,95%CI=1.08-1.62). However, no significant multiplicative interactions werefound between HBV genotypes and polymorphisms of HLA-DP in male or femalesubjects.Conclusions:1. T allele of rs3077, A allele of rs3135021, and A allele of rs9277535were associatedwith decreased risks of HBV infection, while T allele of rs2281388increased the risk ofHBV infection.2. AA genotype of rs9277535was associated with an increased risk of HCC in HBVgenotype C. 3. rs9277535significantly interacted with T1674C/G in the development of HCC ingenotype C.