The Diagnosis of Hypovascular Hepatic Lesions Showing Hypo-intensity in the Hepatobiliary Phase of Gd-EOB- DTPA-enhanced MR Imaging in High-risk Patients for Hepatocellular Carcinoma

The aim of this study was to evaluate the histologic diagnosis of hypovascular hepatic lesions showing hypointensity on hepatobiliary phase images of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI (EOB-MRI). In 38 patients with hepatocellular carcinoma (HCC) after curative treatments and 18 patients with liver cirrhosis, 105 hypovascular nodules that were hypointense at the hepatobiliary phase of EOB-MRI were biopsied and the clinical usefulness of these EOB-MRI findings for the diagnosis of HCC was examined. Of the 105 nodules (median diameter＝12mm), 78 (74.3%), 11 (10.5%), and 16 (15.2%) were diagnosed as HCC, dysplastic, and non-neoplastic, respectively. The positive predictive value (PPV) of hypointensity at the hepatobiliary phase of EOB-MRI for the diagnosis of HCC increased to 77-90% when combined with the following factors: washout appearance on the delayed phase of triple-phase CT, hyperintensity in diffusion-weighted image of MRI, or the appearance of a hypoechoic part in ultrasonography. PPV increased to 100% when all 3 factors were positive. A relatively large proportion of hypovascular lesions that showed hypo-intensity in the hepatobiliary phase were confirmed to be HCC, and the accuracy of HCC increased when combined with other imaging findings

Prognostic Model for Hepatocellular Carcinoma with Time-Dependent Factors

The purpose of this study was to build a prognostic model of hepatocellular carcinoma (HCC) using time-dependent covariates to re-evaluate the prognosis at any stage of the disease. The subjects were consecutive HCC patients who were treated at our institute between 1995 and 2007. We constructed time-fixed and time-dependent prognostic models with a training group (n＝336) and compared the prognostic abilities between conventional Cancer of the Liver Italian Program (CLIP) scores, Japan Integrated Staging (JIS) scores, an Okuda classification, and our prognostic models in the testing group (n＝227) with the c-index. The time-dependent prognostic model consisted of main tumor size, tumor number, portal vein invasion, distant metastasis, alpha-fetoprotein, des-gamma-carboxy prothrombin (DCP), bilirubin, and albumin and the weighted scores were set for each factor depending on the hazard ratio for the prognosis. The prognostic index was determined by summing the scores. The c-index values for the CLIP scores, JIS scores, Okuda classification, and our time-dependent model were 0.741, 0.727, 0.609, and 0.870, respectively. These results indicate that our time-dependent model can estimate the prognosis of HCC more precisely than traditional time-fixed models and can be used to re-predict the prognosis of HCC

Mixed HCV Infection of Genotype 1B and Other Genotypes Influences Non-response during Daclatasvir + Asunaprevir Combination Therapy

Daclatasvir (DCV) + asunaprevir (ASV) combination therapy has become available for patients with hepatitis C virus (HCV) serogroup 1 infection. We studied the efficacy of this therapy by focusing on the factors associated with sustained virological responses (SVR) including resistance-associated variants (RAVs) and mixed infection of different HCV genotypes. We enrolled 951 HCV serogroup 1-positive patients who received this combination therapy at our hospital or affiliated hospitals. The presence of RAVs in non-structural (NS) regions 3 and 5A was analyzed by direct sequencing. HCV genotypes were determined by PCR with genotype-specific primers targeting HCV core and NS5B regions. SVR was achieved in 91.1% of patients. Female sex, age > 70 years, and RAVs were significantly associated with non-SVR (p<0.01 for all). Propensity score-matching results among the patients without RAVs regarding sex, age, and fibrosis revealed that mixed HCV infection determined by HCV NS5B genotyping showed significantly lower SVR rates than 1B-mono infection (p=0.02). Female sex and RAVs were significant factors associated with treatment failure of this combination therapy for patients with HCV serogroup 1 infection. Mixed HCV infection other than 1B-mono infection would be useful for predicting treatment failure

Common Variants in the COL4A4 Gene Confer Susceptibility to Lattice Degeneration of the Retina

Lattice degeneration of the retina is a vitreoretinal disorder characterized by a visible fundus lesion predisposing the patient to retinal tears and detachment. The etiology of this degeneration is still uncertain, but it is likely that both genetic and environmental factors play important roles in its development. To identify genetic susceptibility regions for lattice degeneration of the retina, we performed a genome-wide association study (GWAS) using a dense panel of 23,465 microsatellite markers covering the entire human genome. This GWAS in a Japanese cohort (294 patients with lattice degeneration and 294 controls) led to the identification of one microsatellite locus, D2S0276i, in the collagen type IV alpha 4 (COL4A4) gene on chromosome 2q36.3. To validate the significance of this observation, we evaluated the D2S0276i region in the GWAS cohort and in an independent Japanese cohort (280 patients and 314 controls) using D2S0276i and 47 single nucleotide polymorphisms covering the region. The strong associations were observed in D2S0276i and rs7558081 in the COL4A4 gene (Pc = 5.8×10−6, OR = 0.63 and Pc = 1.0×10−5, OR = 0.69 in a total of 574 patients and 608 controls, respectively). Our findings suggest that variants in the COL4A4 gene may contribute to the development of lattice degeneration of the retina

Loss of runt-related transcription factor 3 expression leads hepatocellular carcinoma cells to escape apoptosis

Background: Runt-related transcription factor 3 (RUNX3) is known as a tumor suppressor gene for gastric cancer and other cancers, this gene may be involved in the development of hepatocellular carcinoma (HCC). Methods: RUNX3 expression was analyzed by immunoblot and immunohistochemistry in HCC cells and tissues, respectively. Hep3B cells, lacking endogenous RUNX3, were introduced with RUNX3 constructs. Cell proliferation was measured using the MTT assay and apoptosis was evaluated using DAPI staining. Apoptosis signaling was assessed by immunoblot analysis. Results: RUNX3 protein expression was frequently inactivated in the HCC cell lines (91%) and tissues (90%). RUNX3 expression inhibited 90 +/- 8% of cell growth at 72 h in serum starved Hep3B cells. Forty-eight hour serum starvation-induced apoptosis and the percentage of apoptotic cells reached 31 +/- 4% and 4 +/- 1% in RUNX3-expressing Hep3B and control cells, respectively. Apoptotic activity was increased by Bim expression and caspase-3 and caspase-9 activation. Conclusion: RUNX3 expression enhanced serum starvation-induced apoptosis in HCC cell lines. RUNX3 is deleted or weakly expressed in HCC, which leads to tumorigenesis by escaping apoptosis

The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force

「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection

DOCK2 is involved in the host genetics and biology of severe COVID-19

「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements