RESUMEN
BACKGROUND AIMS: Previous genome-wide association studies (GWAS) have indicated the involvement of shared (population-non-specific) and non-shared (population-specific) susceptibility genes in the pathogenesis of primary biliary cholangitis (PBC) among European and East-Asian populations. Although a meta-analysis of these distinct populations has recently identified more than 20 novel PBC susceptibility loci, analyses of population-specific genetic architecture are still needed for a more comprehensive search for genetic factors in PBC. APPROACH RESULTS: Protein tyrosine phosphatase non-receptor type 2 (PTPN2) was identified as a novel PBC susceptibility gene locus through a GWAS and subsequent genome-wide meta-analysis involving 2,181 cases and 2,699 controls from the Japanese population (GWAS-lead variant: rs8098858, p=2.6×10-8). In-silico and in-vitro functional analyses indicated that the risk allele of rs2292758, which is a primary functional variant, decreases PTPN2 expression by disrupting Sp1 binding to the PTPN2 promoter in T follicular helper cells (Tfh) and plasmacytoid dendritic cells (pDCs). Infiltration of PTPN2-positive T-cells and pDCs were confirmed in the portal area of the PBC-liver by immunohistochemistry. Furthermore, transcriptomic analysis of PBC-liver samples indicated the presence of a compromised negative feedback loop in-vivo between PTPN2 and IFNG in patients carrying the risk allele of rs2292758. CONCLUSIONS: PTPN2, a novel susceptibility gene for PBC in the Japanese population, may be involved in the pathogenesis of PBC via an insufficient negative feedback loop caused by the PTPN2 risk allele of rs2292758 in IFNï§ signaling. This suggests that PTPN2 could be a potential molecular target for PBC treatment.
RESUMEN
BACKGROUND AND AIM: While several predictive models for the development of hepatocellular carcinoma (HCC) have been proposed, including those for patients with chronic hepatitis C virus (HCV) infection who have achieved sustained virologic response (SVR), the best model may differ between regions. We compared the ability of six reported models to stratify the risk of post-SVR HCC in Japan, where rigorous surveillance and early detection of HCC is common. METHODS: A total of 6048 patients with no history of HCC who achieved SVR by oral direct-acting antiviral drugs were enrolled in this nationwide study. Patients continued HCC surveillance every 6 months after SVR. The incidence of post-SVR HCC was compared between risk groups using the aMAP score, FIB-4 index, Tahata model, GAF4 criteria, GES score, and ADRES score. RESULTS: During the observation period with a median duration of 4.0 years after SVR, post-SVR HCC developed in 332 patients (5.5%). All six models performed significantly at stratifying the incidence of HCC. However, Harrell's C-index was below 0.8 for all models (range, 0.660-0.748), indicating insufficient stratification ability. CONCLUSION: Although all six proposed models demonstrated a good ability to predict the development of post-SVR HCC, their ability to stratify the risk of post-SVRHCC was unsatisfactory. Further studies are necessary to identify the best model for assessing the risk of post-SVR HCC in regions where early detection of HCC is common.
