scholarly journals The Effects and Underlying Mechanisms of Hepatitis B Virus X Gene Mutants on the Development of Hepatocellular Carcinoma

Author(s):  
Rui Pu ◽  
Wenbin Liu ◽  
Xinyu Zhou ◽  
Xiaomei Hou ◽  
Shiliang Cai ◽  
...  

Abstract Background: We aimed to elucidate the mechanism by which hepatitis B virus X (HBx) gene mutations increase the risk of hepatocellular carcinoma (HCC) and identify novel therapeutic targets.Methods: Wild-type and four HBx mutants (M1, A1762T/G1764A; M2, T1674G+T1753C+A1762T/G1764A; M3, C1653T+T1674G+A1762T/G1764A; Ct-HBx, carboxylic acid-terminal truncated HBx) were delivered into the livers of fumarylacetoacetate hydrolase-deficient mice by using the Sleeping Beauty (SB) transposon system, respectively. Seven liver tissues and seven tumor tissues of the SB mouse models were subjected to HBV-capture sequencing. Three liver tissues from WT-HBx mice, three tumor tissues from M3-HBx mice, and three tumor tissues from Ct-HBx mice were subjected to cDNA microarray analysis. HeLa cells stably expressing WT-HBx and the four HBx mutants were also subjected to cDNA microarray assay.Results: The incidence of HCC was higher in the mice injected with M3-HBx or Ct-HBx. M3-HBx had a stronger capacity of upregulating inflammatory cytokines than other HBx variants. HBV-capture sequencing showed that the HBx fragments were mainly integrated into intergenic and intron regions. No significant difference was observed in the number of insertion sites between tumors and liver tissues. Ectopic expression of the HBx mutants, especially M3-HBx and Ct-HBx, significantly increased cell proliferation and the S phase proportion of HepG2 and HeLa cells, compared to WT-HBx. Liver tissues of the SB mice and the transfected cells were subjected to cDNA microarray analysis. Plasminogen activator inhibitor-1 (PAI1) and cell division cycle 20 (CDC20) were identified as novel effectors. M3-HBx and Ct-HBx significantly upregulated the expression of PAI1 and CDC20 in HepG2 and HeLa cells as well as the livers of the SB mice. PAI1 silencing attenuated the effect of M3-HBx and Ct-HBx on the growth of HepG2 cells and greatly decreased the growth of HeLa cells with Ct-HBx. Conclusion: HBx C1653T+T1674G+A1762T/G1764A mutant and Ct-HBx promote carcinogenesis via upregulating PAI1 and CDC20. PAI1, an important player bridging the HBx mutants and HCC, should be a promising candidate as a predictive and prognostic biomarker and therapeutic target in HBV-related HCC.

2013 ◽  
Vol 30 (4) ◽  
pp. 1906-1912 ◽  
Author(s):  
YONG CHEN ◽  
LIJUAN WANG ◽  
HEXIANG XU ◽  
XINGXIANG LIU ◽  
YINGREN ZHAO

2021 ◽  
Vol 27 (1) ◽  
pp. 207-218
Author(s):  
Jeong Won Jang ◽  
Jin Seoub Kim ◽  
Hye Seon Kim ◽  
Kwon Yong Tak ◽  
Heechul Nam ◽  
...  

Background/Aims: The role of hepatitis B virus (HBV) integration into the host genome in hepatocarcinogenesis following hepatitis B surface antigen (HBsAg) seroclearance remains unknown. Our study aimed to investigate and characterize HBV integration events in chronic hepatitis B (CHB) patients who developed hepatocellular carcinoma (HCC) after HBsAg seroclearance.<br/>Methods: Using probe-based HBV capturing followed by next-generation sequencing technology, HBV integration was examined in 10 samples (seven tumors and three non-tumor tissues) from seven chronic carriers who developed HCC after HBsAg loss. Genomic locations and patterns of HBV integration were investigated.<br/>Results: HBV integration was observed in six patients (85.7%) and eight (80.0%) of 10 tested samples. HBV integration breakpoints were detected in all of the non-tumor (3/3, 100%) and five of the seven (71.4%) tumor samples, with an average number of breakpoints of 4.00 and 2.43, respectively. Despite the lower total number of tumoral integration breakpoints, HBV integration sites in the tumors were more enriched within the genic area. In contrast, non-tumor tissues more often showed intergenic integration. Regarding functions of the affected genes, tumoral genes with HBV integration were mostly associated with carcinogenesis. At enrollment, patients who did not remain under regular HCC surveillance after HBsAg seroclearance had a large HCC, while those on regular surveillance had a small HCC.<br/>Conclusions: The biological functions of HBV integration are almost comparable between HBsAg-positive and HBsAgserocleared HCCs, with continuing pro-oncogenic effects of HBV integration. Thus, ongoing HCC surveillance and clinical management should continue even after HBsAg seroclearance in patients with CHB.


2021 ◽  
Vol 2021 ◽  
pp. 1-5
Author(s):  
Shaoliang Zhu ◽  
Hang Ye ◽  
Xiaojie Xu ◽  
Weiru Huang ◽  
Ziyu Peng ◽  
...  

Objective. To investigate the expression of transient receptor potential (TRP) superfamily genes, especially TRPC7-AS1 in hepatitis B virus- (HBV-) related hepatocellular carcinoma (HCC). Methods. Three cancer samples of HBV-related HCC at phase IV and matched paracancerous liver tissues were included in the study. Total RNA was extracted, and differential expression of RNA was screened by high-throughput transcriptome sequencing. The expression of TRPC7-AS1 was detected by quantitative real-time PCR. The N6-adenosyl methylation RNA in MHCC97H, HepG2, and HL-7702 was enriched by coimmunoprecipitation with m6A antibody, and the relative level of N6-adenosyl methylation RNA in TRPC7-AS1 was detected. Results. The expression of TRP family genes in cancer tissues was higher than that in paracancerous liver tissues, including TRPC7-AS1, TRPC4AP, PKD1P6, and PKD1P1. Moreover, the expression level of TRPC7-AS1 in MHCC97H and HepG2 was also significantly higher than that in L02, a normal liver cell. The methylation level of N6-adenosine of TRPC7-AS1 was lower in HepG2 cells than that in L02 cells. Conclusion. TRP superfamily genes, especially TRPC7-AS1, were highly expressed in HBV-related HCC. TRPC7-AS1 could be a potential therapeutic target or diagnostic marker for HCC.


2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Fugui Bai ◽  
Yoshihiko Yano ◽  
Takumi Fukumoto ◽  
Atsushi Takebe ◽  
Motofumi Tanaka ◽  
...  

Pregenomic RNA (pgRNA) is generated from covalently closed circular DNA (cccDNA) and plays important roles in viral genome amplification and replication. Hepatic pgRNA and cccDNA expression levels indicate viral persistence and replication activity. This study was aimed to measure hepatic pgRNA and cccDNA expression levels in various states of hepatitis B virus (HBV) infection. Thirty-eight hepatocellular carcinoma (HCC) patients, including 14 positive for hepatitis B surface antigen (HBsAg) and 24 negative for HBsAg but positive for anti-hepatitis B core (anti-HBc) antibody, were enrolled in this study. In HBsAg-negative but anti-HBc-positive group, HBV-DNA was detected in 20 of 24 (83%) noncancerous liver tissues for at least two genomic regions based on polymerase chain reaction (PCR) analysis. pgRNA and cccDNA expression levels in occult HBV-infected patients were significantly lower than those in HBsAg-positive patients (P<0.001). pgRNA and cccDNA in cancerous tissues were also detected without significant difference from those in noncancerous tissues. In conclusion, cccDNA and pgRNA are detected and represented HBV replication not only in noncancerous but also in cancerous liver tissues. In addition, the replication is shown in not only patients with HBsAg-positive but also occult HBV-infected patients, suggesting the contribution to HCC development.


2012 ◽  
Vol 1 (1) ◽  
pp. 14-24 ◽  
Author(s):  
Su-zhen Jiang ◽  
Jia-jia Zheng ◽  
Xiang-Mei Chen ◽  
Ting Zhang ◽  
Qiang Xu ◽  
...  

Abstract Objective To identify the difference and significance of dominant types of hepatitis B virus (HBV) pre-S mutation between liver tumor tissues and paired adjacent non-tumor tissues and to test if the mutations were tumor tissue specific. Methods HBV DNA isolated from 34 paired intratumoral and peritumoral tissues of hepatocellular carcinoma (HCC) patients were screened by PCR and direct sequencing. All patients carried HBV with genotype C, except for one B/C heterozygote. The expression, localization and excretion of LHBs mutant carrying pre-S deletions were characterized in vitro. The expression of endoplasmic reticulum (ER) GRP78 mRNA was assayed. Results Four patterns of pre-S mutations were identified: pre-S1 in-frame deletion involving the first start codon; pre-S2 in-frame deletion; pre-S2 start codon mutation with or without in-frame deletion; and S promoter in-frame deletion (ΔSP). The first two types were evenly found in both tumor and non-tumor tissues. They were rarely present as dominant strains. The last two types were frequently found in the dominant strains in tumor tissues. The overall prevalence of HBV carrying ΔSP was 17.64% (6/34) in tumor tissues, but none were dominant in nontumor tissues. HBV carrying ΔSP was unable to produce S protein in vitro. Immunocytofluorescence assay showed that the ΔSP LHBs mutant aggregated in the cytoplasm, accumulating mainly in the ER. Transient transfection and expression of ΔSP mutant caused GRP78 up-regulation in vitro. Conclusions HBV S promoter deletion was found dominantly in HCC tumor tissue. The aggregation of mutant large surface proteins in the ER possibly involved in HBV-related HCC.


1988 ◽  
Vol 25 (3) ◽  
pp. 249-258 ◽  
Author(s):  
Ming-Yang Lai ◽  
Ding-Shinn Chen ◽  
Pei-Jer Chen ◽  
Sheng-Chung Lee ◽  
Jin-Chuan Sheu ◽  
...  

Author(s):  
Ying Li ◽  
Chaomin Wang ◽  
Ting Zhao ◽  
Ranliang Cui ◽  
Linfei Hu ◽  
...  

Background: Hepatitis B virus X protein (HBx) is an indispensable progression factor in hepatocellular carcinoma (HCC). CCL15 could be a peculiar proteomic biomarker of HCC with tumorigenesis and tumor invasion. Objective: The aim of study was to explore the relationship between HBx and CCL15 expression in HCC. Methods: HBV–positive HCC pathological tissue samples and corresponding adjacent non-tumor liver tissues were clearly collected. The expression of HBx and CCL15 was analyzed by immunohistochemistry, real-time polymerase chain reaction (PCR) and western blot analysis in tissues or in vitro. Results: The levels of CCL15 mRNA and protein expression in HCC samples were observably higher than the ones of adjacent non-tumor liver tissues. The CCL15 was significantly associated with the expression of HBx in HBV-positive HCC samples. The up-regulation of HBx induced CCL15 expression in vitro. The high expression score of CCL15 was significant associated with the poor prognosis of HCC patients. Conclusions: The CCL15 expression was observably associated with HBx in HCC patients. The CCL15 may be considered as a indicator in clinical managment of HBV-associated HCC.


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