BACKGROUND & AIMS:Different immune cells in tumor microenvironment shape tumor progression. CCL20 over-expression was reported as one of the "stemness" trait in TP53 mutated hepatocellular carcinoma (HCC). We aimed to understand the effect of CCL20 on HCC progression.METHODS:In two HCC cohort patients (n=95, n=85 respectively), serum CCL20 concentration was quantified by using ELISA. Expressions of CCL20 and CCR6 in 41 paired HCC tumor and adjacent non-tumor tissues were determined by quantitative Real-Time PCR, confirmed by immunohistochemistry (CCL20) or by flow cytometry analysis (CCR6). Chemotaxis of splenocytes or purified CD19+ B cells to tumor cell-derived CCL20, and angiogenesis of different CD19+ B subtypes responding to tumor cell-derived CCL20 were measured in vitro. H22 murine hepatoma cells were inoculated into immunocompetent or immunodeficient SCID mice, tumor growth and metastasis were monitored after the mice were treated with anti-CCL20 neutralizing antibody or depleted B cells by anti-CD20.RESULTS:Elevation of pretherapy serum CCL20 in HCC patients and increase of CCR6 expression in HCC tissues were closely associated with tumor metastasis and disease poor prognosis. In HCC tissues, CCL20 expression was positively correlated with CCR6 (R2 =0.3134, P=0.0002), and CCR6 was exclusively identified in tumor infiltrated immune cells. CD19+CD5+ B lymphocytes expressed higher CCR6, responded to tumor cell-derived CCL20 and enhanced angiogenesis in vitro. Neutralizing CCL20 activity in immunocompetent mice, not in SCID mice, attenuated tumor incidence, restrained tumor growth and distal metastasis. Tumor angiogenesis was significantly inhibited after CCL20 activity was blockade. In addition, inhibiting B lymphocyte infiltration into tumor mileum also attenuated tumor growth.CONCLUSIONS:Tumor cell-derived CCL20 interacts with CCR6 highly expressed CD19+CD5+ B cells, to promote HCC progression, which might be via enhancing angiogenesis.
BACKGROUND & AIMS Dietary exposure to aflatoxin is an important risk factor for hepatocellular carcinoma (HCC). However, little is known about the genomic features and mutations of aflatoxin-associated HCCs compared with HCCs not associated with aflatoxin exposure. We investigated the genetic features of aflatoxin-associated HCC that can be used to differentiate them from HCCs not associated with this carcinogen. METHODS We obtained HCC tumor tissues and matched non-tumor liver tissues from 49 patients, collected from 1990 through 2016, at the Qidong Liver Cancer Hospital Institute in China-a high-risk region for aflatoxin exposure (38.2% of food samples test positive for aflatoxin contamination). Somatic variants were identified using GATK Best Practices Pipeline. We validated part of the mutations from whole-genome sequencing and whole-exome sequencing by Sanger sequencing. We also analyzed genomes of 1072 HCCs, obtained from 5 datasets from China, the United States, France, and Japan. Mutations in 49 aflatoxin-associated HCCs and 1072 HCCs from other regions were analyzed using the Wellcome Trust Sanger Institute mutational signatures framework with non-negative matrix factorization. The mutation landscape and mutational signatures from the aflatoxin-associated HCC and HCC samples from general population were compared. We identified genetic features of aflatoxin-associated HCC, and used these to identify aflatoxin-associated HCCs in datasets from other regions. Tumor samples were analyzed by immunohistochemistry to determine microvessel density and levels of CD34 and CD274 (PD-L1). RESULTS Aflatoxin-associated HCCs frequently contained C>A transversions, the sequence motif GCN, and strand bias. In addition to previously reported mutations in TP53, we found frequent mutations in the adhesion G protein-coupled receptor B1 gene (ADGRB1), which were associated with increased capillary density of tumor tissue. Aflatoxin-associated HCC tissues contained high-level potential mutation-associated neoantigens, and many infiltrating lymphocytes and tumors cells that expressed PD-L1, compared to HCCs not associated with aflatoxin. Of the HCCs from China, 9.8% contained the aflatoxin-associated genetic features, whereas 0.4%-3.5% of HCCs from other regions contained these genetic features. CONCLUSIONS We identified specific genetic and mutation features of HCCs associated with aflatoxin exposure, including mutations in ADGRB1, compared to HCCs from general populations. We associated these mutations with increased vascularization and expression of PD-L1 in HCC tissues. These findings might be used to identify patients with HCC due to aflatoxin exposure, and select therapies.
Neonatal hepatitis B vaccination has been implemented worldwide to prevent hepatitis B virus (HBV) infections. Its long-term protective efficacy on primary liver cancer (PLC) and other liver diseases has not been fully examined.The Qidong Hepatitis B Intervention Study, a population-based, cluster randomized, controlled trial between 1985 and 1990 in Qidong, China, included 39,292 newborns who were randomly assigned to the vaccination group in which 38,366 participants completed the HBV vaccination series and 34,441 newborns who were randomly assigned to the control group in which the participants received neither a vaccine nor a placebo. However, 23,368 (67.8%) participants in the control group received catch-up vaccination at age 10-14 years. By December 2013, a total of 3,895 (10.2%) in the vaccination group and 3,898 (11.3%) in the control group were lost to follow-up. Information on PLC incidence and liver disease mortality were collected through linkage of all remaining cohort members to a well-established population-based tumor registry until December 31, 2013. Two cross-sectional surveys on HBV surface antigen (HBsAg) seroprevalence were conducted in 1996-2000 and 2008-2012. The participation rates of the two surveys were 57.5% (21,770) and 50.7% (17,204) in the vaccination group and 36.3% (12,184) and 58.6% (17,395) in the control group, respectively. Using intention-to-treat analysis, we found that the incidence rate of PLC and the mortality rates of severe end-stage liver diseases and infant fulminant hepatitis were significantly lower in the vaccination group than the control group with efficacies of 84% (95% CI 23%-97%), 70% (95% CI 15%-89%), and 69% (95% CI 34%-85%), respectively. The estimated efficacy of catch-up vaccination on HBsAg seroprevalence in early adulthood was 21% (95% CI 10%-30%), substantially weaker than that of the neonatal vaccination (72%, 95% CI 68%-75%). Receiving a booster at age 10-14 years decreased HBsAg seroprevalence if participants were born to HBsAg-positive mothers (hazard ratio [HR] = 0.68, 95% CI 0.47-0.97). Limitations to consider in interpreting the study results include the small number of individuals with PLC, participants lost to follow-up, and the large proportion of participants who did not provide serum samples at follow-up.Neonatal HBV vaccination was found to significantly decrease HBsAg seroprevalence in childhood through young adulthood and subsequently reduce the risk of PLC and other liver diseases in young adults in rural China. The findings underscore the importance of neonatal HBV vaccination. Our results also suggest that an adolescence booster should be considered in individuals born to HBsAg-positive mothers and who have completed the HBV neonatal vaccination series. Please see later in the article for the Editors' Summary.
Qidong City, China, has had high liver cancer incidence from endemic hepatitis B virus (HBV) infection and dietary exposure to aflatoxin. Based on etiologic studies, we began interventions in 1980 to reduce dietary aflatoxin and initiate neonatal HBV vaccination. We studied trends in liver cancer incidence rates in the 1.1 million inhabitants of Qidong and examined trends in aflatoxin exposure, staple food consumption, HBV infection markers and annual income. Aflatoxin exposure declined greatly in association with economic reform, increased earnings and educational programs to shift staple food consumption in the total population from moldy corn to fresh rice. A controlled neonatal HBV vaccination trial began in 1983 and ended in November, 1990, when vaccination was expanded to all newborns. Liver cancer incidence fell dramatically in young adults. Compared with 1980-83, the age-specific liver cancer incidence rates in 2005-08 significantly decreased 14-fold at ages 20-24, 9-fold at ages 25-29, 4-fold at ages 30-34, 1.5-fold at ages 35-39, 1.2-fold at ages 40-44 and 1.4-fold at ages 45-49, but increased at older ages. The 14-fold reduction at ages 20-24 might reflect the combined effects of reduced aflatoxin exposure and partial neonatal HBV vaccination. Decrease incidence in age groups >25 years could mainly be attributable to rapid aflatoxin reduction. Compared with 1980-83, liver cancer incidence in 1990-93 significantly decreased 3.4-fold at ages 20-24, and 1.9-fold at ages 25-29 when the first vaccinees were <11 years old.
Neonatal vaccination against hepatitis B virus (HBV) infection was launched in the 1980s in Qidong, China, where HBV and hepatocellular carcinoma were highly prevalent. Presence of immune memory and immunity against HBV in adults needs to be clarified. From a cohort of 806 who received plasma-derived Hep-B-Vax as neonates and were consecutively followed at ages 5, 10, and 20 years, 402 twenty-four-year-old adults were recruited for booster test. Among them 4 (1%) were found to be HBsAg(+), 27 (6.7%) were HBsAg(-)anti-HBc(+), 121 (30.2%) were HBsAg(-)anti-HBc(-)anti-HBs(+), and 252 (62.4%) were HBsAg(-)anti-HBc(-)anti-HBs(-). Of them, 141 subjects with HBsAg(-)anti-HBc(-) were boosted with 10-μg recombinant HBV vaccine on day-0 and 1-month. The conversion rates of anti-HBs ≥ 10 mIU/ml on D10-12 and 1-month post-booster were 71.4% and 87.3% respectively in the vaccinees who were anti-HBs(+) at age 5, higher than in those who were anti-HBs(-) at age 5, 57.5% and 80.0% respectively, but no statistically significant. After the second dose of booster, all subjects with anti-HBs(+) at age 5 had anti-HBs >500 mIU/ml. However, 6/40 subjects, with anti-HBs(-) at age 5, had anti-HBs <10 mIU/ml, geometric mean concentration was 3.6 (95% CI 2.0-7.7). Of the subjects received booster, 44 subjects were determined the presence of T cell immunity on D10-12, 41 had HBsAg-specific T cells detectable, including 7/10 subjects whose anti-HBs were <10 mIU/ml 10-12 days post-booster. Among 27 HBsAg(-)anti-HBc(+) subjects, 19 had detectable serum HBV-DNA, and an "a" epitope mutation was found in 1/5 HBV isolates. One subject who was anti-HBc(+) at age 20 converted into HBsAg(+) 4 years later. The adults received neonatal HBV vaccination had immune memory and immunity against HBV infection. However, 31.9% of neonatal HBV vaccinees who responded weakly at an early age might be susceptible to HBV infection after childhood.
Previous follow-up on our neonatal HB vaccination cohorts with 80,000 individuals in Qidong, China, showed significant protective efficacy of immunization against HBV infection in childhood. However, some vaccinees were found to be HBsAg negative, but anti-HBs positive and anti-HBc positive at age 10–11 years. To study this phenomenon, 2919 vaccinees at age 19–21 years were sampled from the cohort. HBsAg(−), anti-HBs(+) and anti-HBc(+) were found in 124/2919 (4.2%) of the vaccinees. HBV DNA was detectable in 81/106 sample sera by using nested PCR. The PreS-S regions of HBV were sequenced in 41 randomly sampled sera. All the HBV isolates were HBV genotype C. Twenty one isolates (21/41, 51.2%) were identical to an HBV isolated in this area (GU434374). Only 4/41 (9.8%) showed mutations at the “a” epitope and three of them were G145A. The other mutations were found outside of the “a” epitope. Most of the sera contained <10,000 HBV copies/ml. Occult HBV infection happened in the young adults with HBsAg(−), anti-HBs(+) and anti-HBc(+) status, who received neonatal vaccination in Qidong.
BACKGROUND & AIMS:Mutations in TP53, a tumor suppressor gene, are associated with prognosis of many cancers. However, the prognostic values of TP53 mutation sites are not known for patients with hepatocellular carcinoma (HCC) because of heterogeneity in their geographic and etiologic backgrounds.METHODS:TP53 mutations were investigated in a total of 409 HCC patients, including Chinese (n = 336) and white (n = 73) patients, using the direct sequencing method.RESULTS:A total of 125 TP53 mutations were found in Chinese patients with HCC (37.2%). HCC patients with TP53 mutations had a shorter overall survival time compared with patients with wild-type TP53 (hazard ratio [HR], 1.86; 95% confidence interval [CI]: 1.37-2.52; P < .001). The hot spot mutations R249S and V157F were significantly associated with worse prognosis in univariate (HR, 2.11; 95% CI: 1.51-2.94; P < .001) and multivariate analyses (HR, 1.79; 95% CI: 1.29-2.51; P < .001). Gene expression analysis revealed the existence of stem cell-like traits in tumors with TP53 mutations. These findings were validated in breast and lung tumor samples with TP53 mutations.CONCLUSIONS:TP53 mutations, particularly the hot spot mutations R249S and V157F, are associated with poor prognosis for patients with HCC. The acquisition of stem cell-like gene expression traits might contribute to the aggressive behavior of tumors with TP53 mutation.
Dendritic cells (DCs) have different subtypes with distinct phenotypes and biological functions. Meloyiod dendritic cell subtype is one of the most important DCs subtypes. Recent studies have revealed that human monocytes were composed of CD14++CD16-and CD14+CD16+ subtypes,and mouse monocytes consisted of CD115+Ly6Chigh and CD115+Ly6Clow/-subtypes. Different monocyte subsets differentiate into different dendritic cells subsets with distinct phenotypes and induce different types of immune responses in vivo or in vitro. Under steady state,mouse CD115+Ly6Clow monocyte subtype is an important precursor of dendritic cells in peripheral organs and tissues,but in inflammatory response,CD115+Ly6Chigh monocyte subtype is the main precursor of dendritic cells in peripheral lymphoid organs. CD115+Ly6Chigh monocyte derived dendritic cells can directly present antigens that acquired in peripheral tissues after differentiating into dendritic cells,and transfer their MHC-Ⅰ/peptide complex to residential dendritic cells as well. The cooperation and interaction of dendritic cells from different sources enable the immune system to respond to different stimuli properly.
OBJECTIVE:To identify the association strength of the prevalence of HBeAg, covalently closed circular DNA (cccDNA) and 1762/1764 nucleotide mutations of hepatitis B virus (HBV) with the occurrence of hepatocellular carcinoma (HCC) in Qidong high risk male cohort.METHODS:A cohort of 377 middle aged HBV infected men in Qidong was followed from January 1989 to December 2002. Incident HCC cases were carefully registered. A matched case-controlled study was conducted on 32 pairs of inherent HCC cases with their matched non-HCC controls. Serum HBeAg was measured by ELISA. cccDNA was detected by primer selected PCR. 1762/1764 nucleotide mutations of HBV was identified by PCR of X gene segment spanning the mutation region. Standard statistical comparison between the prevalence of each HBV marker in HCC versus in control group provided the odds ratio with P value to evaluate its association strength with HCC occurrence.RESULTS:Serum HBeAg prevalence was 53.1% (17/32) in HCC group versus and 15.6% (5/32) in controls (OR = 6.12, P < 0.01). Prevalence of serum cccDNA was detected in 62.5% (21/32) of HCC cases but in 25.0% (8/32) of controls (OR = 5.73, P < 0.01). Sequence of detected cccDNA was repeatedly found to be over 90% homologous with HBV. However, the mutation rate of nucleotide 1762/1764 was not found to be statistically higher in the HCC group versus its controls (OR = 1.54, P = 0.425).CONCLUSIONS:The Qidong male case-controlled cohort had shown that serum HBeAg and cccDNA prevalence were tightly associated with hepatocellular carcinoma occurrence in HBV infected men. These biomarkers may have predictive value in earlier diagnosis and therapeutic effect monitoring.
Objective To identify the association strength of the prevalence of HBeAg, cccDNA with the occurrence of HBV related hepatocellular carcinoma (HCC) in high risk male cohort in Qidong area in China. Methods A cohort of 377 middle aged HBV infected men in Qidong was followed from 1989 for 13. 25 years. HCC cases were registered. A matched case-controlled study was conducted on 32 pairs of inherent HCC cases with non-HCC controls. Serum HBeAg was measured by ELISA. cccDNA was detected by semi-nested PCR and verified by DNA sequencing. Standard statistical comparison between the prevalence of each HBV marker in HCC versus control group provided the odds ratio and P-value was used to evaluate its association strength with HCC occurrence. Results Serum HBeAg prevalence was 53. 1% (17/32) in HCC group versus 15. 6% (5/32) in controls, odds ratio (OR) =6. 12, P <0. 01. Prevalence of serum cccDNA was detected in 62. 5% (21/32) of HCC cases and in 21. 8% (8/32) of controls, with OR of 5. 73 and P <0. 01. Sequence of detected cccDNA was, found to be over 90% homologous with HBV. Conclusions A case-controlled study in this cohort showed that serum HBeAg and cccDNA prevalence were highly associated with hepatocellular carcinoma occurrence in HBV infected men. These viral markers may be of predictive value for early HCC diagnosis.
The variability in the prognosis of individuals with hepatocellular carcinoma (HCC) suggests that HCC may comprise several distinct biological phenotypes. These phenotypes may result from activation of different oncogenic pathways during tumorigenesis and/or from a different cell of origin. Here we address whether the transcriptional characteristics of HCC can provide insight into the cellular origin of the tumor. We integrated gene expression data from rat fetal hepatoblasts and adult hepatocytes with HCC from human and mouse models. Individuals with HCC who shared a gene expression pattern with fetal hepatoblasts had a poor prognosis. The gene expression program that distinguished this subtype from other types of HCC included markers of hepatic oval cells, suggesting that HCC of this subtype may arise from hepatic progenitor cells. Analyses of gene networks showed that activation of AP-1 transcription factors in this newly identified HCC subtype might have key roles in tumor development.
BACKGROUND:Hepatocellular carcinoma (HCC) is the second most common cancer in China. Hepatitis B and C viruses (HBV and HCV) and aflatoxins are known risk factors for HCC, but the etiological status of these factors in HCC development is not clear. This study was undertaken to define the absolute importance of HBV in hepatocarcinogenesis of North China.METHODS:A consecutive series of 119 patients with pathologically proven HCC were collected from North China during January 1998 to December 2000 by the Cancer Hospital of the Chinese Academy of Medical Sciences, Beijing. Serum HBsAg, anti-HBc and anti-HCV were negative HBV sero-markers. The HBV X gene was analyzed for its expression by PCR, DNA sequencing, and immunohistochemistry.RESULTS:In the 119 HCC patients, 82.4% (98/119) were HBsAg seropositive. When a comprehensive set of HBV markers were detected, the HBV infection rate in these HCC patients was 99.2% (118/119). Of the patients, 11.8%(14/119) were found to be anti-HCV positive. But all the anti-HCV positive HCC patients were co-infected with HBV.CONCLUSIONS:HBV infection is virtually ubiquitous in HCC patients in North China. The tight association of HBV with HCC strongly suggests the dominant role of HBV infection in causing hepatocellular carcinoma. About 11.8% of HCC patients being HCV-related are co-infected with HBV.
The current metastasis paradigm suggests that the primary tumor starts off benign but over time slowly acquires changes that provide a few rare cells within the tumor the ability to metastasize. However, this concept has been challenged by several recent studies using the microarray-based approach. We have recently found that the molecular signature of primary hepatocellular carcinoma (HCC) is very similar to that of their corresponding metastases, while it differs significantly in primary HCCs with or without metastasis. Similar findings are also evident in primary cancers of the lung, breast, and prostate. Such a signature can be used to predict the prognosis of HCC patients. Moreover, there are significant differences in the gene expression profiles of liver parenchyma among HCC patients with or without intrahepatic metastases. These findings imply that many of the metastasis-promoting genes are embedded in the primary tumors and that the ability to metastasize may be an inherent quality of the tumor from the beginning. In addition, the condition of liver parenchyma may dictate the intrahepatic metastasis potential, which is consistent with the hypothesis that the degree of viral-hepatitis-mediated liver damage or possibly the genetic makeup of individuals may play an important role in metastasis.
This is the first report that a Fusarium toxin nivalenol (NIV) naturally existing at high levels in dietary food in high-risk areas of cancer of esophagus and gastric cardia in China induced benign and malignant tumors in mice. The levels of two Fusarium toxins, nivalenol and deoxynivalenol (DON) were quantitated using high performance liquid chromatography (HPLC) in a total of 97 samples of dietary wheat flour, barley and corn collected from families in two areas with high mortality rate of cancer of esophagus and gastric cardia (132/100,000), Linxian, Henan province and Cixiang, Hepei province, China. The mean level of NIV and DON in three dietary foods was 830+/-927 microg/kg (range 584-1,780 microg/kg) and 4,281+/-6,114 microg/kg (range 732-10,980 microg/kg) respectively. The highest mean level of NIV was 1,780+/-1,705 microg/kg found in barley from Linxian, that of DON was 10,980+/-10,139 microg/kg found in corn from Cixiang. NIV was undetectable in 2 samples of rice from USA. The mean levels of NIV in three main dietary foods in those two high-risk areas were estimated at 400 to 800-fold higher than that in the USA, where NIV was undetectable in dietary food, and the mortality rate of esophageal cancer is <5/100,000 in white Caucasians in the USA, (odds ratio was estimated at 17-34, p<0.000005). These data suggest that Linxian and Cixiang peasants who consumed a diet with high NIV had significantly higher risk for developing esophageal cancer than the US residents who consumed food without or with negligible amounts of NIV. Three repeated experiments were performed using Balb/C mice with inter-mittent application of NIV, alternate with 12-Tetradeconoyl-phorbol-13-acetate (TPA) application on skin. Papillomas and carcinomas developed in a total of 23/49 (47%) mice that survived 11-60 weeks of experiments. Among all the tumors, 4 carcinomas in 3 mice were identified. No tumors were found in the 60 control mice applying either TPA or acetone (solvent) only on skin.
Objective To define the importance of HBV and HCV infection in pathogenesis of hepatocellular carcinoma (HCC) in North China. Methods A consecutive series of 119 patients with HCC living in North China who were treated in our hospital were included in this study. Serum HBsAg, anti-HBc and anti-HCV were detected by Abbotts AxSym System. For those patients with negative detection of HBV sero-markers, HBV X gene was analyzed with nested PCR, DNA sequencing and immunohistochemistry for its expression. Results Amongst the 119 patients, 98 (82.4%) were HBsAg sero-positive. When a comprehensive set of HBV markers were detected, the rate of HBV infection in these patients reached the level of 99.2% (118/119). Of the 119 cases, 14 (11.8%) were found to be anti-HCV positive. However, all the anti-HCV positive cases had co-infection of HBV. Conclusions In North China, HBV infection is closely related to pathogenesis of HCC. Meanwhile, HBV infection is the major cause for HCC in this region. HCV is an important auxiliary factor for HCC.
OBJECTIVE:To study the inhibitory effect of RNA interference (RNAi) on c-myc expression in hepatocellular carcinoma cell line, HepG2.METHODS:Expression vector of c-myc gene-targeting small interference RNA (siRNA) was constructed (psilencer-c-myc) and transfected into HepG2 cells by lipofectamine, and the unloaded vector was used as control (mock). The expression of c-myc mRNA and protein was identified by quantitive PCR and Western blot. Apoptosis of the transfected cells was examined by flow cytometry and immunofluorescent microscopy.RESULTS:After HepG2 cells were transfected with psilencer-c-myc, the expression of c-myc mRNA and protein was suppressed with an inhibition rate of 67% compared with the mock-transfected cells. Apoptosis was identified in the transfected HepG2 cells.CONCLUSION:The expression of c-myc at transcriptional and translational levels in HepG2 cells transfected with siRNA is markedly inhibited, which may be associated with the induction of apoptosis.
We analyzed global gene expression patterns of 91 human hepatocellular carcinomas (HCCs) to define the molecular characteristics of the tumors and to test the prognostic value of the expression profiles. Unsupervised classification methods revealed two distinctive subclasses of HCC that are highly associated with patient survival. This association was validated via 5 independent supervised learning methods. We also identified the genes most strongly associated with survival by using the Cox proportional hazards survival analysis. This approach identified a limited number of genes that accurately predicted the length of survival and provides new molecular insight into the pathogenesis of HCC. Tumors from the low survival subclass have strong cell proliferation and antiapoptosis gene expression signatures. In addition, the low survival subclass displayed higher expression of genes involved in ubiquitination and histone modification, suggesting an etiological involvement of these processes in accelerating the progression of HCC. In conclusion, the biological differences identified in the HCC subclasses should provide an attractive source for the development of therapeutic targets (e.g., HIF1a) for selective treatment of HCC patients.
Objective To investigate the expression status of HBV X gene,TGF-alpha,c-myc,beta-catenin and 249 codon mutation of p53 in HCC cell lines for exploring their possible role in hepatocarcinogenesis in area of prevalence.Methods Cell lines 7701 and 7703 derived from Qidong HCC were used.HBV X gene in cell DNA was identified by PCR and sequencing.X gene expression was assessed by RT-PCR and Western Blot.249 codon mutation status of p53 gene was analyzed by PCR-RFLP.The expression level of TGF-alpha,c-myc and beta-catenin was determined by immuno-cytochemistry.Results Presence of partical HBV X gene sequence was identified by PCR and confirmed by DNA sequencing in both cell lines.This was consistent with negative findings at transcriptional and translational level by RT-PCR and Western Blot.130、131 codon variation of X gene was found in both cell line.PCR-RFLP demonstrated that the 249 codon of p53 gene was of wild type.Strong expression of TGF-alpha,c-myc,beta-catenin protein was shown in both cell lines by immunocytochemistry.Conclusion In both cell lines,HBV X gene sequences are identified as a genetic marker of previous HBV exposure.The X gene is not expressed,possibly as a result of truncation near 3′end.The 249 codon of p53 gene is of wild type.Strong expression of TGF-alpha,c-myc and beta-catenin suggests their possible role in hepatocarcinogenesis.