Liping Pan

Evaluation of susceptibility locus for response to interferon-α based therapy in chronic hepatitis B patients in Chinese.

In 2009, three independent genome-wide association studies reported that genetic variation in the interleukin 28B gene to be associated with the response to interferon-α/ribavirin therapy in hepatitis C virus genotype 1 infected patients. We carried out the present study to assess whether such polymorphisms also affect the therapy effect of another interferon-α responsive illness as chronic hepatitis B. Five hundred and twelve interferon-α treatment-naïve HBeAg seropositive chronic hepatitis B patients were enrolled in the present retrospective nested case-control study. All patients received PEG-IFN-α-2a based treatment and were examined for the therapy efficacy. SNP rs8099917 was genotyped using the MassArray system (Sequenom). Interestingly, the frequency of G allele of rs8099917 was significantly higher in response group than in non response group (8.3% vs. 3.9%, p=0.003, OR=0.44, 95%CI=0.25-0.79). The genotype distributions of this SNP also differed significantly between two groups (p=0.003). Our study suggested that the G allele of rs8099917 was associated with higher rate of response in HBeAg seropositive chronic hepatitis B patients treated with interferon α.

Association between polymorphisms of the cytokine and cytokine receptor genes and immune response to hepatitis B vaccination in a Chinese Han population

The immune response to hepatitis B vaccination varies among individuals. It has been reported that polymorphisms in cytokine and cytokine receptor genes are associated with these individual differences. The aim of the current study was to investigate the association between polymorphisms of the Th1/Th2 cytokine and cytokine receptor genes and the response to hepatitis B vaccination in a Chinese Han population. A total of 10 single nucleotide polymorphisms distributed in 6 genes (TNFRSF1A, IL12A, IL12B, IFNG, IL4, and IL10) were genotyped in 214 high‐responders [hepatitis B surface antibody (anti‐HBs) ≥1,000 mIU/ml] and 107 low‐responders (anti‐HBs: 10–99 mIU/ml). The minor CTCTAA allele of rs17860508 in the IL12B gene was associated with a low response to hepatitis B vaccination (P = 0.039, odds ratio = 1.41, 95% confidence interval = 1.00–1.99). In addition, a significant gene–gene interaction was found: the frequency of the combined genotypes IL12A rs2243115 TT and IL12B rs17860508 CTCTAA/CTCTAA was significantly higher in the low‐response group than in the high‐response group (P = 0.008, odds ratio = 2.19, 95% confidence interval = 1.23–3.93). These findings suggest that polymorphisms in the IL12A and IL12B genes might play an important role jointly in determining the response to hepatitis B vaccination. J. Med. Virol. 84:26–33, 2011.

Association of NKG2D genetic polymorphism with susceptibility to chronic hepatitis B in a Han Chinese population

Natural killer (NK) cells are important antiviral effectors of innate immunity because of their contribution to virus elimination. NK cell‐mediated immunological reaction to hepatitis B virus (HBV) infection depends on a fine balance between inhibitory and activating receptors. The aim of the study was to investigate genetic polymorphisms in NK cell receptors (NKR)—KLRD1 (CD94), KLRK1 (NKG2D), KLRC4 (NKG2F), and KLRC1 (NKG2A)—to evaluate the association of NKR genetic polymorphisms with susceptibility to chronic hepatitis B in a Han Chinese population. Twelve single nucleotide polymorphisms (SNPs), including rs2302489 in CD94; rs2255336, rs2617160, rs7980470, rs 2734565, and rs17513986 in NKG2D; rs2617170, rs17549004, and rs3825295 in NKG2F; rs2734414, rs7301582, and rs2734440 in NKG2A, were selected in the present study. SNP genotyping was undertaken in 500 Han Chinese patients (285 patients with chronic hepatitis B and 215 patients who cleared HBV spontaneously) by a polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) and by the TaqMan method. Single marker association analysis was conducted and the SNP rs2617160 with a TT genotype in NKG2D was associated significantly with an increased risk of chronic hepatitis B (P = 0.044; OR = 1.49; 95% CI = 1.01–2.19). Haplotype analysis with multiple loci indicated that there was no significant association between the haplotypes of the NKR genes and susceptibility to chronic hepatitis B. The SNP rs2617160 in NKG2D associated with susceptibility to chronic hepatitis B in a Han Chinese population. J. Med. Virol. 82:1501–1507, 2010.

Polymorphisms in the VEGFA promoter are associated with susceptibility to hepatocellular carcinoma by altering promoter activity.

Accumulated evidences indicate that single nucleotide polymorphisms (SNP) in angiogenesis and tumorigenesis related genes are associated with risk of hepatocellular carcinoma (HCC). Vascular endothelial growth factor A (VEGFA), one of the most significant mediators of angiogenesis, plays an important role in carcinogenesis and development via promoting tumor growth. We carried out a two‐stage association study in 1,838 chronic hepatitis B (CHB) patients and 1,207 hepatitis B virus (HBV) related HCC patients in Han Chinese populations from Beijing, Guangxi and Jiangsu. We systematically screened polymorphisms in the VEGFA gene and examined the association between the SNPs and susceptibility to HCC. Functional analyses were conducted to verify biological significances of associated SNPs. We identified two promoter SNPs (rs833061 and rs1570360) were associated with susceptibility to HCC (rs833061: ptrend = 0.008 in Youan_Beijing samples, ptrend = 0.01 in Guangxi samples, ptrend = 0.01 in Jiangsu samples. rs1570360: ptrend = 0.00003 in Youan_Beijing samples, ptrend = 0.006 in Guangxi samples, ptrend = 0.02 in Jiangsu samples). These two SNPs were further validated in four independent groups of major HBV outcomes, indicating rs833061 and rs1570360 may associate exclusively to HCC. Functional analyses show that CA haplotype constructed by rs833061 and rs1570360 had higher luciferase activity compared with TG haplotype (p < 0.05). A 18 bp insert/del polymorphism was in absolute linkage disequilibrium (LD) with rs833061. The 18 bp insert allele created a Sp1 binding site. We observed higher VEGFA transcription in peripheral blood of HCC patients compared with CHB patients and healthy individuals (p < 0.05). These findings indicate that VEGFA promoter SNPs may contribute to susceptibility of HCC by altering promoter activity.

CD3Z genetic polymorphism in immune response to hepatitis B vaccination in two independent Chinese populations.

Vaccination against hepatitis B virus is an effective and routine practice that can prevent infection. However, vaccine-induced immunity to hepatitis B varies among individuals. CD4+ T helper cells, which play an important role in both cellular and humoral immunity, are involved in the immune response elicited by vaccination. Polymorphisms in the genes involved in stimulating the activation and proliferation of CD4+ T helper cells may influence the immune response to hepatitis B vaccination. In the first stage of the present study, a total of 111 single nucleotide polymorphisms (SNPs) in 17 genes were analyzed, using the iPLEX MassARRAY system, among 214 high responders and 107 low responders to hepatitis B vaccination. Three SNPs (rs12133337 and rs10918706 in CD3Z, rs10912564 in OX40L) were associated significantly with the immune response to hepatitis B vaccination (P = 0.008, 0.041, and 0.019, respectively). The three SNPs were analyzed further with the TaqMan-MGB or TaqMan-BHQ probe-based real-time polymerase chain reaction in another independent population, which included 1090 high responders and 636 low responders. The minor allele ‘C’ of rs12133337 continued to show an association with a lower response to hepatitis B vaccination (P = 0.033, odds radio = 1.28, 95% confidence interval = 1.01–1.61). Furthermore, in the stratified analysis for both the first and second populations, the association of the minor allele ‘C’ of rs12133337 with a lower response to hepatitis B vaccination was more prominent after individuals who were overweight or obese (body mass index ≥25 kg/m2) were excluded (1st stage: P = 0.003, 2nd stage: P = 0.002, P-combined = 9.47e-5). These findings suggest that the rs12133337 polymorphism in the CD3Z gene might affect the immune response to hepatitis B vaccination, and that a lower BMI might increase the contribution of the polymorphism to immunity to hepatitis B vaccination.

Evaluation of the Association Between the ADRA2A Genetic Polymorphisms and Type 2 Diabetes in a Chinese Han Population

Alpha-2-adrenergic receptor (ADRA2A) is involved in the sympathetic nervous system and plays a role in the regulation of insulin secretion and lipolysis. Recent studies have indicated that the ADRA2A polymorphisms are associated with type 2 diabetes (T2DM) in Caucasians and African Americans. The present study aimed to evaluate the association between the ADRA2A polymorphisms and T2DM in a Chinese Han population. Two single-nucleotide polymorphisms (SNPs) rs521674 and rs553668 in the ADRA2A gene were genotyped in 2094 Chinese subjects (1042 T2DM patients and 1052 nondiabetic controls) by using the TaqMan allelic discrimination technique. A single-locus analysis indicated that SNP rs553668 was associated with T2DM (p=0.04). Further analysis indicated that the association of SNP rs553668 was found in T2DM patients with body mass index (BMI)<25 kg/m(2) (p=0.03), but not in the patients with BMI≥25 kg/m(2) (p=0.56). This association was still significant in a recessive model (p=0.01, odds ratio=0.68, 95% confidence interval=0.51-0.92). In conclusion, the present study provides evidence that the ADRA2A polymorphism, rs553668, is associated with lean T2DM patients in a Chinese Han population. Further investigation to explore the role of ADRA2A in the regulation of body weight has been taken into our consideration.

BTNL2 associated with the immune response to hepatitis B vaccination in a Chinese Han population

No response to hepatitis B vaccination is a complex phenomenon, which is induced by the combinations of environmental and genetic factors. The aim of the study was to investigate the association between the polymorphisms of the butyrophilin‐like 2 (BTNL2) gene and the immune response to hepatitis B vaccination in a Chinese Han population. A total of 7 single nucleotide polymorphisms in the BTNL2 gene were analyzed in 566 non‐responders and 1,040 high‐responders to hepatitis B vaccination. The alleles T, T, C, A, G of rs3763316, rs3763311, rs9268494, rs3806156, and rs2076530 were associated with no response to hepatitis B vaccination (P = 0.015, odds ratio (OR) = 1.20; P = 0.029, OR = 1.18; P = 2.00E−07, OR = 1.58; P = 0.002, OR = 1.27; P = 2.90E−06, OR = 1.41, respectively). Whereas, the alleles T, C of rs9268501 and rs3763313 played significantly protective roles in the immune response to hepatitis B vaccination (P = 0.007, OR = 0.81; P = 0.004, OR = 0.74). Besides, the risks of no response to hepatitis B vaccination were increased significantly among individuals harbored the haplotypes of G‐T‐A‐T‐C‐A‐G (P = 0.038, OR = 1.48), G‐T‐A‐T‐C (P < 0.0001, OR = 2.34), A‐A (P < 0.0001, OR = 4.08), and C‐G (P < 0.0001, OR = 4.75). However, the haplotype of G‐C‐A‐T‐C (P = 1.00E−04, OR = 0.54) exhibited a protective role in the immune response to hepatitis B vaccination in the study. These findings suggest that polymorphisms in the BTNL2 gene might play a vital role in determining the outcome of the immune response to hepatitis B vaccination. J. Med. Virol. 86:1105–1112, 2014.

Association of Polymorphisms in Mitofusin-2 Gene with Type 2 Diabetes in Han Chinese

MFN2 and ESRRA are candidate genes involved in the pathogenesis of T2D. Five tag-SNPs in MFN2 gene and three in ESRRA gene were selected and genotyped with TaqMan or PCR-RFLP method in stage 1 populations (555 patients with T2D and 649 control subjects) and stage 2 populations (546 patients with T2D versus 419 control subjects) in Han Chinese. And combining our published data, we estimated the interactions between genetic variants in the MFN2, ESRRA, and PGC-1α genes on the T2D risk using MDR. rs873458 (G > A) and rs2878677 (C > T) in MFN2 gene were significantly associated with T2D (P = 0.005 and 0.01) in stage 1 populations, and the association of other SNPs with T2D was not found. In stage 2 populations, we further confirmed the association between rs2878677 and T2D (P = 0.01). Combining the two stage populations, the data supported more significant effect of rs873458 and rs2878677 on T2D risk (P = 0.003 and 0.0001). A-C-G-T-C and G-T-C-T-C in MFN2 had significant association with T2D (P = 0.007 and 0.009). The present study also provided the evidence that MFN2 had interactions with PGC-1α (P < 0.0001) or ESRRA (P < 0.0001). This study suggested a role of MFN2 polymorphism in the risk of T2D; however, further studies are needed.

Polymorphisms in ADAR1 gene affect response to interferon alpha based therapy for chronic hepatitis B in Han Chinese

Host genetic polymorphisms in interferon pathway genes are reported to be associated with response to interferon therapy. Five hundred and forty-eight α interferon treatment-naïve chronic hepatitis B patients were enrolled in the retrospective nested case-control study. All patients received α interferon based treatment and were examined for therapy efficacy. We genotyped 115 polymorphisms from 16 interferon pathway genes using the MassArray system. We identified rs4845384 in ADAR1 gene is strongly associated with the outcome of interferon therapy allele dose-depended (P=0.0005), with decreased odds ratios of 0.69 and 0.27 for GA and AA genotypes, respectively (95% confidence interval, 0.47-0.99 for GA; 0.11-0.64 for AA). Our study suggested that rs4845384 in ADAR1 associates with treatment-induced clearance of chronic hepatitis B.

Human leukocyte antigen class I and class II genes polymorphisms might be associated with interferon α therapy efficiency of chronic hepatitis B

Certain host genetic polymorphisms in human leukocyte antigen (HLA) genes are reported to be associated with response to interferon α (IFNα) therapy. Two hundred and eighteen IFNα treatment-naïve chronic hepatitis B (CHB) patients were enrolled in the present study. HLA-A, B, C and DQA1, DQB1, DRB1 gene alleles were detected by polymerase chain reaction-sequencing based typing (PCR-SBT) and PCR-sequence specific primer (PCR-SSP), respectively. Frequencies of HLA-DQB1*0303 and DRB1*08 in response group were clearly lower than those in nonresponse group (P=0.019, OR=1.81, 95%CI=1.07-3.15; P=0.031, OR=2.43, 95%CI=1.02-5.98, respectively). Frequencies of haplotype *1101-*4601-*0102 (HLA-A, B, C) and haplotype *0302-*0303-*09 (HLA-DQA1, DQB1, DRB1) were clearly lower than those in nonresponse group (P=0.009, OR=4.84, 95%CI=1.29-19.48; P=0.031, OR=1.94, 95%CI=1.01-3.73, respectively). These results suggest that patients with HLA-DQB1*0303 or DRB1*08 alleles, and haplotype *1101-*4601-*0102 (HLA-A, B, C) or haplotype *0302-*0303-*09 (HLA-DQA1, DQB1, DRB1), might be less responsive to IFNα treatment.