Identification of novel susceptibility loci associated with hepatitis B surface antigen seroclearance in chronic hepatitis B
PLOS ONE
Authors: Kim, Tae Hyung; Lee, Eun-Ju; Choi, Ji-Hye; Yim, Sun Young; Lee, Sunwon; Kang, Jaewoo; Lee, Yoo Ra; Lee, Han Ah; Choi, Hyuk Soon; Kim, Eun Sun; Keum, Bora; Seo, Yeon Seok; Vim, Hyung Joon; Jeen, Yoon Tee; Chun, Hoon Jai; Lee, Hong Sik; Kim, Chang Duck; Woo, Hyun Goo; Um, Soon Ho
Abstract
Background/Aims The seroclearance of hepatitis B virus (HBV) surface antigen (HBsAg) is regarded as a functional cure of chronic hepatitis B (CHB) although it occurs rarely. Recently, several genome-wide association studies (GWASs) revealed various genetic alterations related to the clinical course of HBV infection. However, all of these studies focused on the progression of HBV infection to chronicity and had limited application because of the heterogeneity of HBV genotypes. In the present study, we aimed to determine susceptibility genetic markers for seroclearance of HBsAg in CHB patients with a homogenous viral genotype. Methods One hundred patients with CHB who had experienced HBsAg seroclearance before 60 years of age and another 100 with CHB showing high serum levels of HBsAg even after 60 years of age were enrolled. Extreme-phenotype GWAS was conducted using blood samples of participants. Results We identified three single nucleotide polymorphisms, rs7944135 (P=4.17 x 10(-6), odds ratio [OR] = 4.16, 95% confidence interval [CI] = 2.27-7.63) at 11q12.1, rs171941 (P=3.52x10(-6), OR = 3.69, 95% CI = 2.13-6.42) at 5q14.1, and rs6462008 (P = 3.40 x 10(-6), OR = 0.34, 95% CI = 0.22-0.54) at 7p15.2 as novel susceptibility loci associated with HBsAg seroclearance in patients with CHB. The flanking genes at these loci including MPEG1, DTX4, MTX3, and HOXA13 were suggested to have functional significance. In addition, through functional analysis, CXCL13 was also presumed to be related. Conclusions To the best of our knowledge, this study is the first GWAS regarding the seroclearance of HBsAg in CHB patients. We identify new susceptibility loci for cure of CHB, providing new insights into its pathophysiology.
E3 ubiquitin ligase DTX4 is required for adipogenic differentiation in 3T3-L1 preadipocytes cell line
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Authors: Wang, Zonggui; Dai, Zhong; Pan, Yaqiong; Wu, Simin; Li, Zhengli; Zuo, Changqing
Abstract
Deltex4 (DTX4) is a member of the Deltex family of proteins. To date several lines of evidences suggest that Deltex family of proteins is closely linked to cell development and cell differentiation. However, little is known about the role of DTX4 in adipogenic differentiation. In this study, we assessed the impact of DTX4 on adipogenic differentiation in vitro, we found that DTX4 protein expression gradually increased during adipogenic differentiation of 3T3-L1 preadipocytes cell line. While DTX4 stable knockdown by recombinant shRNA lentivirus (sh-DTX4) notably reduced the number of lipid droplets and down regulated the expression of adipogenic transcription factors C/EBP alpha and PPAR gamma and adipogenic markers gene FABP4 and Adipsin. Besides, cell numbers and incorporation of 5-Ethynyl-2'-deoxyuridine (EdU) into cells were significantly decreased during mitotic clonal expansion (MCE) in sh-DTX4 cells postinduction. Furthermore, compared to recombinant shRNA lentivirus control group (sh-CON), the mRNA levels of Wnt signaling genes such as Wnt6, Wnt10b and beta-catenin, were obviously elevated in sh-DTX4 group at day 3 of postinduction. Taken together, our results indicate that DTX4 stable knockdown inhibits adipogenesis of 3T3-L1 cells through inhibiting C/EBPa and PPAR gamma, arresting mitotic clonal expansion and regulating Wnt signaling pathway. (C) 2017 Elsevier Inc. All rights reserved.