Regulatory factor X5 promotes hepatocellular carcinoma progression by transactivating tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein theta and suppressing apoptosis / 中华医学杂志(英文版)

Background@#Our previous studies have shown that regulatory factor X5 (RFX5), a classical transcription regulator of MHCII genes, was obviously overexpressed in hepatocellular carcinoma (HCC) tumors. However, the role of RFX5 in the carcinogenesis and progress of HCC remains unknown. This study aimed to reveal its biological significance and the underlying mechanism in HCC.@*Methods@#RFX5 mRNA expression level and copy number variation in HCC tumors and cell lines were determined by analyzing deposited data sets in the Cancer Genome Atlas and Gene Expression Omnibus database. The biological significance of RFX5 in HCC was investigated by monitoring the colony formation and subcutaneous tumor growth capacity when RFX5 was silenced with lentiviral short hairpin RNA and CRISPR/Cas9 system in HCC cell lines. The downstream gene transcriptionally activated by RFX5 in HCC cells was determined by chromatin immunoprecipitation and luciferase reporter assay. The involvement of tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein theta (YWHAQ) in HCC development was further determined by performing colony formation rescue assay and subcutaneous tumor growth rescue experiment. The association of YWHAQ with recurrence-free survival of patients with HCC was assessed by Kaplan-Meier analysis. Moreover, apoptosis level and the protein level of p53 pathway were determined to reveal the mechanism of RFX5 in driving HCC development.@*Results@#RFX5 was amplified and highly overexpressed in HCC tumor tissues compared with the corresponding non-tumor tissues. The mRNA expression level of RFX5 was significantly correlated with its DNA copy number (r = 0.4, P < 0.001). Functional study demonstrated that RFX5 was required for both clonogenic forming in vitro and subcutaneous tumor growth in vivo of HCC cells. Further study identified YWHAQ, namely 14-3-3 tau, as a key downstream transcriptional target gene of RFX5, which was tightly regulated by RFX5 in HCC. Moreover, overexpression of YWHAQ largely rescued the clonogenic growth of HCC cells that was suppressed by RFX5 knockdown. In addition, overexpression of YWHAQ in primary tumor was linked to poor prognosis of patients with HCC. These results demonstrated that YWHAQ was a downstream effector of RFX5 in HCC. Notably, RFX5-YWHAQ pathway could protect cells from apoptosis by suppressing the p53 and Bax in HCC.@*Conclusion@#RFX5 is a putative HCC driver gene that plays an important role in the development and progression of HCC by transactivating YWHAQ and suppressing apoptosis.

Regulatory factor X5 promotes hepatocellular carcinoma progression by transactivating tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein theta and suppressing apoptosis / 中华医学杂志(英文版)

BACKGROUND@#Our previous studies have shown that regulatory factor X5 (RFX5), a classical transcription regulator of MHCII genes, was obviously overexpressed in hepatocellular carcinoma (HCC) tumors. However, the role of RFX5 in the carcinogenesis and progress of HCC remains unknown. This study aimed to reveal its biological significance and the underlying mechanism in HCC.@*METHODS@#RFX5 mRNA expression level and copy number variation in HCC tumors and cell lines were determined by analyzing deposited data sets in the Cancer Genome Atlas and Gene Expression Omnibus database. The biological significance of RFX5 in HCC was investigated by monitoring the colony formation and subcutaneous tumor growth capacity when RFX5 was silenced with lentiviral short hairpin RNA and CRISPR/Cas9 system in HCC cell lines. The downstream gene transcriptionally activated by RFX5 in HCC cells was determined by chromatin immunoprecipitation and luciferase reporter assay. The involvement of tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein theta (YWHAQ) in HCC development was further determined by performing colony formation rescue assay and subcutaneous tumor growth rescue experiment. The association of YWHAQ with recurrence-free survival of patients with HCC was assessed by Kaplan-Meier analysis. Moreover, apoptosis level and the protein level of p53 pathway were determined to reveal the mechanism of RFX5 in driving HCC development.@*RESULTS@#RFX5 was amplified and highly overexpressed in HCC tumor tissues compared with the corresponding non-tumor tissues. The mRNA expression level of RFX5 was significantly correlated with its DNA copy number (r = 0.4, P < 0.001). Functional study demonstrated that RFX5 was required for both clonogenic forming in vitro and subcutaneous tumor growth in vivo of HCC cells. Further study identified YWHAQ, namely 14-3-3 tau, as a key downstream transcriptional target gene of RFX5, which was tightly regulated by RFX5 in HCC. Moreover, overexpression of YWHAQ largely rescued the clonogenic growth of HCC cells that was suppressed by RFX5 knockdown. In addition, overexpression of YWHAQ in primary tumor was linked to poor prognosis of patients with HCC. These results demonstrated that YWHAQ was a downstream effector of RFX5 in HCC. Notably, RFX5-YWHAQ pathway could protect cells from apoptosis by suppressing the p53 and Bax in HCC.@*CONCLUSION@#RFX5 is a putative HCC driver gene that plays an important role in the development and progression of HCC by transactivating YWHAQ and suppressing apoptosis.

Effect of Upregulated DNA Replication and Sister Chromatid Cohesion 1 Expression on Proliferation and Prognosis in Hepatocellular Carcinoma / 中华医学杂志(英文版)

Background@#DNA replication and sister chromatid cohesion 1 (DSCC1) (also called DCC1) is a component of an alternative replication factor C complex that loads proliferating cell nuclear antigen onto DNA during S phase of the cell cycle. It is located at 8q24 and frequently amplified in hepatocellular carcinoma (HCC). However, the role of DSCC1 in the carcinogenesis and progress of HCC has not been fully investigated. Here, we aimed to assert the importance of DSCC1 in the HCC.@*Methods@#In this study, copy number variation data and RNA sequencing data were used to calculate the DNA copy number and mRNA expression of DSCC1 in HCC. Quantitative polymerase chain reaction, Western blotting, and immunohistochemistry analysis were used to determine the mRNA and protein level of DSCC1 in HCC. The Kaplan-Meier analysis and univariate and multivariate Cox regression analysis were used to assess the association of DSCC1 with the overall survival (OS) of HCC patients. Moreover, lentiviral shRNA was used to knockdown DSCC1, and then, colony-forming assay, cell cycle assay, and cell proliferation assay were performed to evaluate the impact of DSCC1 silencing on HCC cell lines.@*Results@#We found that DSCC1 was amplified and highly expressed in HCC tumor tissues than in nontumor tissues. We then found that the overexpression of both mRNA and protein of DSCC1 was linked to the bad prognosis of HCC patients. Astonishingly, the protein level of DSCC1 was an independent prognostic factor for OS (hazard ratio, 1.79; 95% confidence interval, 1.17-2.74; P = 0.007). Furthermore, the clonogenic capacity of DSCC1-amplified HCC cell lines (MHCC-97H, MHCC-97L, and Hep3B) was significantly inhibited by transduction of a lentiviral shRNA that targets DSCC1. We also showed that knockdown of DSCC1 induced G0-G1 cell cycle arrest (increased from 60% to more than 80%) and greatly inhibited the proliferation of HCC cell lines.@*Conclusion@#These results suggest that DSCC1 is a putative HCC driver gene that promotes proliferation and is associated with poor prognosis in HCC.

Direct-acting Antiviral Agents Resistance-associated Polymorphisms in Chinese Treatment-naïve Patients Infected with Genotype 1b Hepatitis C Virus / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>It has been reported that several baseline polymorphisms of direct-acting antivirals (DAAs) agents resistance-associated variants (RAVs) would affect the treatment outcomes of patients chronically infected with hepatitis C virus (CHC). The aim of this study is to investigate the prevalence of DAAs RAVs in treatment-naÏve GT1b CHC patients.</p><p><b>METHODS</b>Direct sequencing and ultra-deep sequencing of the HCV NS3, NS5A, and NS5B gene were performed in baseline serum samples of treatment-naÏve patients infected with genotype 1b hepatitis C virus (HCVs).</p><p><b>RESULTS</b>One hundred and sixty CHC patients were studied. Complete sequence information was obtained for 145 patients (NS3), 148 patients (NS5A), and 137 patients (NS5B). Treatment-failure associated variants of DAAs were detected: 56.6% (82/145) of the patients presented S122G for simeprevir (NS3 protease inhibitor); 10.1% (14/148) of the patients presented Y93H for daclatasvir and ledipasvir (NS5A protein inhibitors); 94.2% (129/137) of the patients presented C316N for sofosbuvir (NS5B polymerase inhibitor). Nearly, all of the DAAs RAVs detected by ultra-deep sequencing could be detected by direct sequencing.</p><p><b>CONCLUSIONS</b>The majority of genotype 1b CHC patients in China present a virus population carrying HCV DAAs RAVs. Pretreatment sequencing of HCV genome might need to be performed when patients infected with GT1b HCV receiving DAAs-containing regimens in China. Population sequencing would be quite quantified for the work.</p>

Correlation between interleukin-28B genetic polymorphisms and primary hepatocellular carcinoma / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the correlation between single nucleotide polymorphisms (SNPs) of interleukin-28B (IL-28B) gene and the susceptibility to primary hepatocellular carcinoma (HCC).</p><p><b>METHODS</b>A total of 300 histologically confirmed HCC cases (from November 2001 to April 2010) and 310 healthy controls with no history of chronic hepatitis B or hepatocellular carcinoma (2009-2010) were selected from a hospital in Guilin and a hospital in Beijing for this case-control study.139 HCC patients in the case group had complete clinical tracking data. All the subjects were Han Chinese, with no age or gender restrictions.2 ml peripheral blood samples were drawn from each subject with informed consent. SNP of rs12972991, rs4803223, rs8099917 and rs12979860 four loci in IL-28B gene were analyzed by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF).</p><p><b>RESULTS</b>The frequencies of C allele at rs12972991, G allele at rs8099917 and G allele at rs4803223 were 6.7% (40/598), 7.9% (47/598) and 10.0% (59/588) respectively in case group; all higher than the corresponding frequencies in control group, separately 2.9% (18/618), 4.1% (25/616) and 3.6% (21/608). The differences were statistically significant (χ2=9.542, 7.858, 20.736, P values all<0.05). The above alleles could increase the risk of HCC, and the OR (95%CI) values were separately 1.67 (1.13-2.46), 1.49 (1.08-2.06) and 2.91 (1.79-4.72). The genotype frequencies of AC+CC at rs12972991, GT+GG at rs8099917, GA+GG at rs4803223 were 13.0% (39/299), 14.7% (44/299) and 19.0% (56/296) respectively in case group; while the frequencies were lower in control group, separately 5.8% (18/309), 8.1% (25/308) and 6.6% (20/304). The differences were statistically significant (χ2=9.319, 6.557, 20.948, P values all<0.05). These genotypes may increase the risk of HCC, and the adjusted OR (95%CI) values were 2.24 (1.31-3.83), 1.81 (1.14-2.88) and 2.90 (1.78-4.70), respectively. The stratified analysis of the clinical data indicated that the frequency of genotype GA+GG at rs4803223 was 50.0% (13/26) in patients of tumor thrombosis in portal vein (TTPV), higher than the frequency of genotype AA (21.1%, 23/109). The difference was statistically significant (χ2=8.965, P=0.003).</p><p><b>CONCLUSION</b>The results suggested that IL-28B gene polymorphisms was correlated to the susceptibility to HCC in Chinese Han ethnic population. Among them, GA + GG genotype at rs4803223 could increase the risk of TTPV in HCC patients.</p>

Intestinal immune barrier integrity in rats with nonalcoholic hepatic steatosis and steatohepatitis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Nonalcoholic fatty liver disease (NAFLD) has emerged as the major cause of chronic liver injury. Intestinal barrier plays an important role in the pathogenis of NAFLD. The aim of this article was to assess intestinal immune barrier function during the development of NAFLD.</p><p><b>METHODS</b>Totally 60 male Sprague-Dawley (SD) rats were divided into 2 groups: normal diet (ND) group and high-fat diet (HFD) group. NAFLD rat model was established in the HFD rat group. Portal blood endotoxin level was assessed by limulus test. The percentage of CD4+ cells and CD8+ cells in peripheral blood mononuclear cells (PBMC) and lymphocytes in Peyer's patches (PP) were analysed by flow cytometry. Intestinal secretory immunoglobulin A (SIgA) level was evaluated by enzyme-linked immunosorbent assay. Paired Student's t test was used for the statistic analysis.</p><p><b>RESULTS</b>HFD rats presented with simple steatosis at the 4th and 8th week and progressed to nonalcoholic steatohepatitis at the 12th week. Elevated lipopolysaccharides (LPS) level in HFD rats was observed at the 8th week ((1.54 ± 0.30) times of ND group, P < 0.01). CD4/CD8 ratios in PBMC and PP of HFD rats were increased at the 4th week ((1.50 ± 0.47) and (1.63 ± 0.34) times of ND group, P < 0.05) and decreased at the 8th week ((0.50 ± 0.16) and (0.61 ± 0.26) times of ND group, P < 0.05). At the 12th week, CD4/CD8 ratio ((1.47 ± 0.46) times, P < 0.05) in PP increased to levels observed in the 4th week. Intestinal SIgA expression of HFD rats was remarkably up-regulated at 12th week ((2.70 ± 1.65) times, P < 0.05).</p><p><b>CONCLUSION</b>Liver-gut axis in rats with NAFLD may mediate and improve intestinal immune function by increased CD4/CD8 ratio in PP and increased production of SIgA.</p>