ABSTRACT
<p><b>OBJECTIVE</b>To evaluate whether first-degree family history of liver cancer plays a role in liver cancer incidence by prospective evaluation of a patient cohort in Qidong, China over a 20-year period.</p><p><b>METHODS</b>In May 1992, 708 hepatitis B surface antigen (HBsAg) carriers and 730 HBsAg-negadve controls from Qidong city were enrolled for participation in a prospective cohort study ending in November 2012.Follow-up was carried out every 6 to 12 months, and evaluations included serum assays to measure concentrations of alpha fetoprotein (AFP), HBsAg and alanine aminotransferase (ALT), as well as abdominal ultrasound to assess liver disease.The relationship between baseline (study entry) information of patients with first-degree family history of liver cancer and liver cancer incidence during the two decades of study was statistically assessed.</p><p><b>RESULTS</b>There were 172 newly diagnosed liver cancer cases in the cohort during 25 753 person-years (py) of follow-up, representing an incidence of 667.88/100 000 py.The incidence rates of liver cancer among participants with or without liver cancer family history were 1 244.36/100 000 py and 509.70/100 000 py respectively, and the between-group difference reached the threshold for statistical significance (P less than 0.01, Relative Risk (RR):2.44, 95% Confidence Interval (CI):1.80-3.31).The incidence rates of liver cancer among participants who had a sibling with liver cancer and participants who had a parent with liver cancer were not significantly different (P > 0.05), but the liver cancer incidence among participants who had a mother with liver cancer was significantly higher than that of participants who had a father with liver cancer (P < 0.05, RR:1.86, 95% CI:1.03-3.36). Among the participants with liver cancer family history, 56.52% (39/69) were diagnosed before 50 years old, and this rate was significantly higher than that of participants without a family history of liver cancer (40.78%, 42/103, P less than 0.05).The incidence rate of liver cancer among the participants who were family history-positive and HBsAg-positive was significantly higher than that of participants who were family history-negative but HBsAg-positive (P < 0.01, RR:1.75, 95% CI:1.29-2.38), and was 59.59 times higher than for participants who were family history-negative and HBsAgnegative.Subgroup analysis of liver cancer incidence among participants who were family history-positive but HBsAg-negative and participants who were family history-negative and HBsAg-negative produced anRR of 2.60, but there was no statistically significant difference between the two subgroups (P > 0.05).At the study's end, the incidence rates of liver cancer for the different subgroups were 32.21% for the family history-positive and HBsAgpositive participants, 19.80% for the family history-negative and HBsAg-positive participants, 1.71% for the family history-positive and HBsAg-negative participants, and 0.65% for the family history-negative and HBsAg-negative participants.</p><p><b>CONCLUSION</b>First-degree family history of liver cancer is a risk factor of liver cancer in Chinese patients from Qidong, and exhibits synergism with HBsAg-positivity for incidence of liver cancer.</p>
Subject(s)
Humans , Middle Aged , Alanine Transaminase , Carrier State , China , Cohort Studies , Hepatitis B Surface Antigens , Incidence , Liver Neoplasms , Epidemiology , Prospective Studies , Risk Factors , alpha-FetoproteinsABSTRACT
Objective To determine the factors responsible for failed postnatal immunoprophylaxis for hepatitis B virus(HBV) in Qidong, China. Methods Eleven children who developed into chronic HBV infection after receiving HBIG and HBV recombinant vaccines were recruited into the study. Eleven paired mothers with chronic hepatitis and other 6 mothers whose children successfully generated anti-HBs after im-munoprophylaxis were included as the control in the study. Full-length HBV DNA was amplified through ser-um sample by PCR method and underwent cloning and sequencing. HBV DNA level was quantified by real-time PCR. Results The mean levels of HBV DNA in mothers who had HBV DNA positive children and healthy children were ( 1.2 ×107± 3.1 × 106 ) copies/ml and ( 1.6× 107±8.8×106 ) copies/ml, respec-tively. There was no significant difference between the groups (P >0.05). Meanwhile, viral load in chil-dren was unrelated to that in their mothers (r2 =0.2429). In 11 HBV DNA positive children, 4(36.4% ) demonstrated amino acid substitutions in HBsAg "a" determinant region with 6 different types, I.e. T125A, I126T, Q129H, M133V, D144V and G145A. All of the mothers showed the wild-type sequence in "a" epitope, indicating surface escape mutants were not acquired from the initial infection, but developed under the immune pressure. The mutation rates after immunoprophylaxis for preS1, preS2, S, X, preC/C and P genes were 0.38%, 0. 22%, 0.27%, 0.17%, 0.11%, and 0.11%, respectively, nt2999-3157 in preS1, nt529-677 in S, nt1955-2016 in C, nt923-1001 and nt2489-2602 in P genes were among the hottest muta-tional spots throughout the HBV genome. Conclusion HBV mutation may occur in all the open readingframes after passive and active immunoprophylaxis. In addition to S gene, HBV preS and P genes could alsoassociate with the escape mutants.
ABSTRACT
<p><b>BACKGROUND</b>To study the structure and function of 2.2 kb spliced variant of HBV genome from liver tissues of hepatocellular carcinoma patients.</p><p><b>METHODS</b>HBV genomes were amplified by using PCR from paired hepatocellular carcinoma tissues and peritumor tissues. The 3.2 kb full-length HBV genome and 2.2 kb spliced variant were separately cloned and sequenced. Hep G2 cells were co-transfected with full-length HBV DNA and 2.2 kb spliced variant, and after transfection, HBV DNAs from intracellular core particles were harvested and specific primers were used in PCR to evaluate the interactions between spliced variant and full-length counterpart in replication.</p><p><b>RESULTS</b>Semi-quantification by scanning density showed that 2.2 kb spliced variant was present in all tumor and peri-tumor samples studied. Sequence analyes revealed that the 5 terminus packaging signal for pregenomic and X and PreC/C genes were retained. When full-length HBV DNA was co-transfected with 2.2 kb, the replication signal of 3.2 kb HBV genome was increased 3-7 times.</p><p><b>CONCLUSIONS</b>The 2.2 kb HBV spliced variant was present in liver tissues, and relative content was higher in tumor tissues than that in the peri-tumor tissues. This spliced variant could enhance the replication of full-length HBV genome, which suggested the possible role of the variant in the pathogenesis of development of hepatocellular carcinoma.</p>