Sirinporn Suksawatamnuay

Colon Cancer Prevention by Detection of APC Gene Mutation in a Family with Attenuated Familial Adenomatous Polyposis

BACKGROUND Genetic mutation is a significant factor in colon CA pathogenesis. Familial adenomatous polyposis (FAP) is an autosomal dominant hereditary disease characterized by multiple colorectal adenomatous polyps affecting a number of cases in the family. This report focuses on a family with attenuated familial adenomatous polyposis (AFAP) with exon 4 mutation, c.481C>T p.Q161X of the APC gene. METHODS We analyzed 20 members of a family with AFAP. Clinical and endoscopic data were collected for phenotype determination. Genetic analysis was also performed by direct sequencing of the APC gene. RESULT Five patients with a phenotype of AFAP were found. Endoscopic polyposis was demonstrated among the second generation with genotype mutation of the disease (age > 50 years) consistent with delayed phenotypic adenomatous polyposis in AFAP. APC gene mutation was identified in exon 4 of the APC gene, with mutation points of c.481C>T p.Q161X. Laparoscopic subtotal colectomy was performed to prevent carcinogenesis. CONCLUSION A family with attenuated familial adenomatous polyposis of APC related to exon 4 mutation, c.481C>T p.Q161X, was reported and the phenotypic finding was confirmed by endoscopic examination. Genetic mutation analysis might be advantageous in AFAP for long term colon cancer prevention and management due to subtle or asymptomatic phenotype presentation in early adulthood.

Genetic variation in the vitamin D pathway CYP2R1 gene predicts sustained HBeAg seroconversion in chronic hepatitis B patients treated with pegylated interferon: A multicenter study

Evidence of a role of vitamin D in the immune system is increasing. Low serum vitamin D is associated with increased hepatitis B virus replication. Genome-wide association study (GWAS) data has revealed a number of the single nucleotide polymorphisms (SNPs) within the vitamin D synthetic pathway that affect vitamin D functions. We aimed to determine the association between SNPs in the vitamin D gene cascade and response to pegylated interferon (PegIFN) therapy in hepatitis B e-antigen (HBeAg)-positive patients. One hundred and eleven patients treated for 48 weeks with PegIFN-alfa 2a at 13 hospitals were retrospectively evaluated. Thirteen SNPs derived from vitamin D cascade-related genes, including DHCR7 (rs12785878), CYP27B1 (rs10877012), CYP2R1 (rs2060793, rs12794714), GC (rs4588, rs7041, rs222020, rs2282679), and VDR (FokI, BsmI, Tru9I, ApaI, TaqI), were genotyped. Thirty-one patients (27.9%) seroconverted to HBeAg after 24 weeks of treatment. Multivariate analysis found pretreatment qHBsAg <10,000 IU/mL (OR = 7.73, 95% CI: 2.36–25.31, P = 0.001), CYP2R1 rs12794714 TT genotype (OR = 4.16, 95% CI: 1.07–16.25, P = 0.04), and baseline ALT >2 times the upper limit of normal (OR = 3.83, 95% CI: 1.31–11.22, P = 0.014) predicted sustained HBeAg seroconversion after completion of PegIFN treatment. HBV DNA during study period tended to be lower with the rs12794714 CYP2R1 TT than the non-TT genotype. The rs12794714 CYP2R1 polymorphism may be a useful pretreatment factor predictive of sustained HBeAg seroconversion after PegIFN therapy. This study provides evidence that not only vitamin D level but also genetic variation of CYP2R1 in the vitamin D cascade influences host immune response in chronic HBV infection.

Association between CXCL10 and DPP4 Gene Polymorphisms and a Complementary Role for Unfavorable IL28B Genotype in Prediction of Treatment Response in Thai Patients with Chronic Hepatitis C Virus Infection.

Pretreatment serum levels of interferon-γ-inducible protein-10 (IP-10, CXCL10) and dipeptidyl peptidase-4 (DPP IV) predict treatment response in chronic hepatitis C (CHC). The association between functional genetic polymorphisms of CXCL10 and DPP4 and treatment outcome has not previously been studied. This study aimed to determine the association between genetic variations of CXCL10 and DPP4 and the outcome of treatment with pegylated interferon-α (PEG-IFN-α) based therapy in Thai patients with CHC. 602 Thai patients with CHC treated using a PEG-IFN-α based regimen were genotyped for CXCL10 rs56061981 G>A and IL28B rs12979860 C>T. In addition, in patients infected with CHC genotype 1, DPP4 (rs13015258 A>C, rs17848916 T>C, rs41268649 G>A, and rs 17574 T>C) were genotyped. Correlations between single nucleotide polymorphisms, genotype, and treatment response were analyzed. The rate of sustained virologic response (SVR) was higher for the CC genotype of IL28B rs12979860 polymorphisms than for non-CC in both genotype 1 (60.6% vs. 29.4%, P < 0.001) and non-genotype 1 (69.4% vs. 49.1%, P < 0.05) CHC. SVR was not associated with the CXCL10 gene variant in all viral genotypes or DPP4 gene polymorphisms in viral genotype1. Multivariate analysis revealed IL28B rs12979860 CC genotype (OR = 3.12; 95% CI, 1.72–5.67; P < 0.001), hepatitis C virus RNA < 400,000 IU/ml (OR = 2.21; 95% CI, 1.22–3.99, P < 0.05), age < 45 years (OR = 2.03; 95% CI, 1.11–3.68; P < 0.05), and liver fibrosis stage 0–1 (OR = 1.64; 95% CI, 1.01–2.65, P < 0.05) were independent factors for SVR. Unfavorable IL28B rs12979860 CT or TT genotypes with the CXCL10 rs56061981 non-GG genotype were associated with a higher SVR than GG genotype (66.7% vs. 33.0%, P = 0.004) in viral genotype 1. In Thai CHC genotype 1 infected patients with an unfavorable IL28B rs12979860 CT/TT genotype, the complementary CXCL10 polymorphism strongly enhances prediction of treatment response.

Vitamin D supplementation improves serum markers associated with hepatic fibrogenesis in chronic hepatitis C patients: A randomized, double-blind, placebo-controlled study

Hepatic fibrosis is the net accumulation of matrix tissue components which controlled by pro-fibrolytic enzymes, matrix metalloproteinases (MMPs), and pro-fibrotic cytokine, TGF-β1, and enzymes, tissue inhibitors of MMPs (TIMPs). Vitamin D (VD) supplementation has been shown to reverse these processes in vitro and in vivo. This study sought to determine the effect of VD supplementation on serum fibrotic markers in chronic hepatitis C (CHC) patients. Fifty-four CHC patients with VD deficiency were randomized into two groups, a VD group (n = 29) and a placebo group (n = 29). The serum levels of 25-hydroxy VD, TGF-β1, TIMP-1, MMP2 and MMP9 were measured at baseline and at the end of the 6-week study period. Upon correction of VD levels, TGF-β1 and TIMP-1 levels were decreased, and the MMP2 and MMP9 levels were significantly increased in the VD group. A comparison of the mean changes (delta) in the markers between groups showed that TGF-β1 and TIMP-1 levels were significantly decreased and the MMP2 and MMP9 were significantly higher in the VD group than in the placebo group. By using CHC patients as a model, this study provides additional evidence that VD plays an important role in the reversal of hepatic fibrogenesis.

Correction of vitamin D deficiency facilitated suppression of IP-10 and DPP IV levels in patients with chronic hepatitis C: A randomised double-blinded, placebo-control trial

Vitamin D deficiency was common among patients with chronic hepatitis C (CHC) and had negative influence on treatment outcome. Correction of vitamin D deficiency improved treatment response. Interferon gamma-induced protein 10 (IP-10) and enzyme dipeptidyl peptidase-4 (DPP IV) involved in inflammatory responses in CHC. Their higher levels at pretreatment of CHC could predict poorer responses. Vitamin D suppressed expression of IP-10 from monocytes in vitro. In CHC patients, DPP IV involved in IP-10 regulation. We hypothesized that correction of vitamin D insufficiency or deficiency in CHC patients might restore immune dysregulation through a pathway linked to the TH1/Th2 cytokines, IP-10 or DPP IV. We conducted a double-blind, placebo-controlled trial. 80 CHC patients with vitamin D levels less than 30 ng/mL were assigned to receive vitamin D (40) or placebo (40) supplements for 6 weeks. The levels of 25-hydroxyvitamin D [25(OH)D], Th1/Th2 cytokines, IP-10 and DPP IV were measured at baseline and at the 6th week. At the end of study, the mean 25(OH)D level in vitamin D group was significantly increased and normalised. There were no changes in the level of Th1/Th2 cytokines. Our important finding revealed that upon correction of vitamin D insufficiency or deficiency, the serum IP-10 and DPP IV levels were decreased significantly as compare to the placebo group (delta changes; 83.27 vs -133.80; 95% CI [-326.910, -40.758], p = 0.0125, and 271.04 vs -518.69; 95% CI [-1179,15, -59.781], p = 0.0305, respectively. As previous evidences suggested that each factor individually influenced and predicted outcome of CHC treatment. Our results offer a new insight and help to piece the puzzle of vitamin D deficiency, IP-10 and DPP IV together in CHC. Trial registration: Thai Clinical Trials Registry TCTR20160429001

Mo1023 The Single Nucleotide Polymorphism in the Vitamin D Pathway DHCR7 Gene and Pre-Treatment HBV-DNA Strongly Predict HBeAg Loss in HBeAg-Positive Chronic Hepatitis B Patients Treated With Pegylated Interferon: Multicenter Study

Aim: Clinical outcome after hepatitis B virus (HBV) exposure vary extremely from spontaneous clearance to chronic hepatitis B and often progresses to liver cirrhosis and hepatocellular carcinoma. Host genetic factor plays an important role in the regulation of immune response. The study was designed to investigate whether (HLA) class II DQA1 and DQB1 gene polymorphism are associated with chronic hepatitis B infection and whether it leads to the development of HBV related liver cirrhosis (LC) and hepatocellular carcinoma (HCC) in north Indian population. Methods: We have assessed the DQA1 and DQB1 allele polymorphism in 187 HBV related liver diseases which included (73 chronic hepatitis B, 84 LC, and 30 HCC patients) and 109 controls who had spontaneously recovered from HBV infection by using polymerase chain reaction amplification with sequence specific primers (PCR-SSP). Results: The data suggest that DQA1*0101/2/4 (OR=2.78; P=0.003), DQA1*0103 (OR= 2.64; P=0.0007) and DQB1*0302/3 (OR=2.15; P=0.01) were associated with protection from chronic HBV infection, while DQB1*0402 (OR=0.25; P=0.001) conferred susceptibility to chronic HBV infection, respectively. It was also observed that DQB1*0601 (OR=3.73; P=0.006) conferred protective effect from developing Liver Cirrhosis, similarly DQB1*0302/ 3 (OR=5.53; P=0.05) and DQB1*0402 (OR=0.00; P=0.0001) conferred protective effect from progressing to HCC. Though, DQA1*0601 and DQB1*0503 showed some susceptible effect on chronic HBV infection, these association were no longer significant after Bonferroni correction (P=0.23, P=0.59). Conclusion: The results suggest that various subtypes of HLA-DQA1 and DQB1 does influence the HBV clearance and development of chronic HBV infections in north Indian population.

Su1030 Genetic Variation in Vitamin D Pathway DHCR7 Gene Predicts Poor Response to Pegylated Interferon-Alfa Based Therapy in Asian Chronic Hepatitis C Genotype 1-Infected Patients

were descriptively evaluated for observed self-reportedQOL (SF-36v2) andwork productivity and activity impairment (WPAI) assessments. Assessments were scored such that lower SF36v2 Mental Component Summary (MCS) and Physical Component Summary (PCS) scores corresponded to lower QOL while higher WPAI scores represented higher levels of impairment and work time missed. Results: Among the 71,157 NHWS total respondents, 0.9% reported an HCV diagnosis, 1.3% CHF, 2.8% MI, 5.0% COPD, 10.9% Diabetes, 14.9% Depression, and 17.3%OA. Among these 7 cohorts, the HCV cohort was the second youngest with a mean age of 54 years and had the second highest proportion of male respondents (69.8%). The HCV cohort was observed to have the second lowest average MCS scores (44.6) among the seven cohorts while having mean PCS scores (43.7) that were numerically third highest (Table 1.). Full-time employment was reported by 25.0% of the HCV group, 17.2% COPD, 28.9% Depression, 14.7% MI, 20.2% OA, 11.4% HF, and 24.4% Diabetes. Numerically, the HCV cohort had the second highest reported overall work impairment scores (29.5%) among the seven conditions and was ranked between cohorts for mean total activity impairment scores (39.8%). Conclusions: Results provide further insight into QOL and productivity as reported by a population of US survey respondents with HCV. Although one-fourth of survey respondents with HCV reported full-time employment, these same individuals reported productivity losses in the forms of absenteeism and presenteeism. Further evaluation of the impact of comorbidity burden and HCV treatment on these patient outcomes is warranted. Table 1. Cohort Mean Scores

360 CXCL10 GENE POLYMORPHISM PREDICTS RAPID VIROLOGIC RESPONSE TO PEGYLATED INTERFERON/RIBAVIRIN COMBINATION THERAPY IN ASIAN PATIENTS WITH DIFFICULT-TO-TREAT CHRONIC HEPATITIS C GENOTYPE

Background and Aims: HLA-diversity is a major host genetic risk factor in infectious diseases. In particular, several studies have described associations between distinct HLA alleles and outcomes of HCV and HIV infection. The objective of this study was to analyse the distribution of HLA Class I alleles in HIV/HCV co-infected individuals in order to identify HLA-disease associations that reflect the impact of this dual infection. Methods: Clinical data from 1110 Caucasian patients (HCV: n =477, HIV: n =181, HIV and HCV: n =346, healthy controls: n = 106) were retrieved by retrospective chart review. HLA-A and B allele distribution were determined by molecular methods (SSO and SSP) with HLA-resolution reduced to the 2-digit level to enable uniform comparisons. Fisher’s exact test and Chi-square tests with Yates correction for multiple testing were applied for statistical analysis. Results: Patients with HCV mono-infection were significantly older than patients in each other group (p < 0.001). MSM was the predominant risk factor for HIV infection (52%), while most HIV/HCV and HCV-infected patients had been infected via blood exposure (83%). The frequency of HLA alleles HLA-A*30 (p =0.023), HLA-B*08 (p =0.003), HLA-B*39 (p =0.003), and HLAB*49 (p =0.032) did not differ between the patient groups but was significantly reduced in infected patients as compared to healthy controls irrespective from the underlying type of infection. In contrast, HLA-B*57, which is assumed to increase chances of spontaneous HCV resolution and delay HIV progression, was selectively increased in patients with HIV mono-infection (13%) as compared to each other group (healthy controls: 9%, HIV/HCV and HCV mono-infection: 6% each; p =0.022). Conclusion: Reduced detection rates in HIVor HCV-monoand HIV/HCV co-infected patients indicate that alleles HLA-A*30, HLAB*08, HLA-B*39, and HLA-B*49 carry a poor prognosis but do not reflect interactions between HIVand HCV-infections. Patients with blood-borne infections usually acquire HCV first and HIV later on. Thus, finding a high HLA-B57 carrier rate in HIV+ patients but in none of the other groups indicates a protective role of this allele for both HIV and HCV infection. Taken together long-term exposure of Caucasian patients to HIV and HCV infection seems to induce subtle footprints in their HLA class I repertoire.

610 The Promoter Polymorphism of Cyp27b1 Gene Predicts Poor Response to Interferon-Alfa Based Therapy in Difficult-to-Treat Chronic Hepatitis C Genotype in Asian Population

Background and aims: Vitamin D plays an important role in both innate and adaptive immune systems. Recently, vitamin D deficiency has been proposed as a novel predictor of poor-response of treatment with pegylated interferon-alfa and ribavirin in patients with chronic hepatitis C. CYP27B1 or 25-hydroxyvitamin D3-1α-hydroxylase catalyzes metabolic activation of 25-hydroxyvitamin D3 into 1α, 25-dihydroxyvitamin D3, an active form of vitamin D. The CYP27B1-1260 promoter polymorphisms are known to influence 1 α, 25dihydroxyvitamin D3 serum level. This study was performed to determine the association between the CYP27B1 gene polymorphism and outcome of treatment with pegylated interferon-alpha based therapy in patients with chronic hepatitis C in Asian population. Methods: 261 patients with chronic hepatitis C treated with pegylated interferon-alfa based regimen were genotyped for the promoter (-1260) polymorphism rs 10877012 C.A of the CYP27B1 gene. The definitions of rapid viral response (RVR), early viral response (EVR), end of treatment viral response (EOT) and sustained viral response (SVR) were made according to the American Association for the Study of Liver Diseases (AASLD). Results: Of these, 177 patients (67.8%) achieved SVR. 101 patients (38.7%) were genotype 1 or 4. Baseline characteristics including age, gender, body mass index, alcohol consumption, genotypes, baseline HCV RNA viral load, serum alanine aminotransferase and advanced fibrosis were not statistically different between patients with SVR and non-SVR. The overall SVR rate were 58.9%, 72.4% and 67.1 for CC, CA, and AA genotype, respectively, p=0.20. SVR was not different in CC genotype compared to non-CC genotype (58.9% vs 70.2%, p=0.15). However, in genotype 1/4-infected patients, SVR rate was significant lower in CC genotype than nonCC genotype (36.4% vs 65.8%, p=0.016), (Figure 1). Patients with EVR had lower AA genotype than non-EVR (28.7% vs 53.8%, p=0.01). There were no association between CYP27B1-1260 promoter polymorphism and rate of RVR and EOT. In difficult-to-treat HCV genotype (1/4), proportion of CC genotype was significant higher in patients with non-SVR than SVR (34.1% vs 13.3%, p=0.01). In these cases, age and CC genotype were significantly associated with non-SVR. Multivariate logistic regression analysis found CC genotype (Odds ratio = 4.8, 95% CI = 1.61-14.54, p = 0.005) and age (Odds ratio = 1.07, 95%CI = 1.021.12, p=0.01) were independent predictor of non-SVR. Conclusions: This study suggested that in Asian population, the CYP27B1 promoter (-1260) CC polymorphism was a strong predictor of poor response of treatment with pegylated interferon-alfa based regimen in patients with difficult-to-treat genotype chronic hepatitis C.