Localization of a susceptibility locus for hepatocellular carcinoma to chromosome 4q in a hepatitis B hyperendemic area

Nonsyndromic cleft lip with or without cleft palate and cancer: Evaluation of a possible common genetic background through the analysis of GWAS data

Previous research suggests a genetic overlap between nonsyndromic cleft lip with or without cleft palate (NSCL/P) and cancer. The aim of the present study was to identify common genetic risk loci for NSCL/P and cancer entities that have been reported to co-occur with orofacial clefting. This was achieved through the investigation of large genome-wide association study datasets. Investigations of 12 NSCL/P single nucleotide polymorphisms (SNPs) in 32 cancer datasets, and 204 cancer SNPs in two NSCL/P datasets, were performed. The SNPs rs13041247 (20q12) and rs6457327 (6p21.33) showed suggestive evidence for an association with both NSCL/P and a specific cancer entity. These loci harbor genes of biological relevance to oncogenesis (MAFB and OCT4, respectively). This study is the first to characterize possible pleiotropic risk loci for NSCL/P and cancer in a systematic manner. The data represent a starting point for future research by identifying a genetic link between NSCL/P and cancer.

Relationship between the mechanism of hepatitis B virus father-infant transmission and pregnancy outcome

PURPOSE

This study examined the relationship between the mechanism of hepatitis B virus (HBV) father-infant transmission via reproductive cells and pregnancy outcome.

METHODS

Abandoned in vitro fertilization (IVF) embryos of fathers with chronic HBV infection were taken as study objects. HBV mRNA in embryos was detected, and successfully transplanted embryos were followed up to determine the relationship between HBV-infected embryos and pregnancy outcome.

RESULTS

HBV mRNA signals were detected in one embryo in the group with HBV-positive fathers; the positive rate was 1/18 (5.5%). IVF embryos of HBV-positive fathers with HBV mRNA signals were successfully implanted, but early abortion occurred.

CONCLUSIONS

HBV mRNA was found in abandoned IVF embryos of HBV-infected fathers, which confirmed that HBV could not only enter early cleavage embryos via sperm but also replicate in embryos, resulting in HBV father-infant transmission. HBV may interfere with embryonic development and thus affect pregnancy outcome.

Genetic variation at 8q24, family history of cancer, and upper gastrointestinal cancers in a Chinese population

Genetic variation at 8q24 is associated with prostate, bladder, breast, colorectal, thyroid, lung, ovarian, UADT, liver and stomach cancers. However, a role for variation at 8q24 in familial clustering of upper gastrointestinal cancers has not been studied. In order to explore potential inherited susceptibility, we analyzed epidemiologic data from a population-based case-control study of upper gastrointestinal cancers from Taixing, China. The study population includes 204 liver, 206 stomach, and 218 esophageal cancer cases and 415 controls. Associations between 8q24 rs1447295, rs16901979, rs6983267 and these cancers were stratified by family history of cancer. Odds ratios and 95% confidence intervals were adjusted for potential confounders: age, sex, education, tobacco smoking, alcohol consumption, and BMI at interview. We also adjusted for hepatitis B and aflatoxin (liver cancer) and Helicobacter pylori (stomach cancer). In a dominant model, among those with a family history of cancer, rs1447295 was positively associated with liver cancer (OR(adj) 2.80; 95% CI 1.15-6.80). Heterogeneity was observed (P(heterogeneity) = 0.029) with rs6983267 and liver cancer, with positive association in the dominant model among those with a family history of cancer and positive association in the recessive model among those without a family history of cancer. When considered in a genetic risk score model, each additional 8q24 risk genotype increased the odds of liver cancer by two-fold among those with a family history of cancer (OR(adj) 2.00; 95% CI 1.15-3.47). These findings suggest that inherited susceptibility to liver cancer may exist in the Taixing population and that variation at 8q24 might be a genetic component of that inherited susceptibility.

Prospective cohort studies of association between family history of liver cancer and risk of liver cancer

Uncertainty remains on the relationship between a family history of liver cancer and liver cancer risk in prospective cohort studies in a general population. Thus, we examined this association in 133,014 participants in the Shanghai Women's and Men's Health Studies. Family history of liver cancer was categorized through dichotomous and proportional score approaches. Hazard ratios (HRs) and 95% confidence intervals (CIs) were derived using the Cox proportional hazards models with adjustment for potential confounders. A meta-analysis of observational studies through December 2013 on liver cancer risk in relation to family history of liver cancer was also performed. Study-specific risk estimates were combined using fixed or random effects models depending on whether significant heterogeneity was detected. For the Shanghai Women's and Men's Health Studies, 299 liver cancer cases were identified during follow-up through 2010. Family history of liver cancer was associated with liver cancer risk using both binary indicator (HR = 2.60, 95% CI: 1.77-3.80) and proportional score (high-risk vs. minimal-risk category: HR = 3.03, 95% CI: 1.73-5.31), with increasing HRs for increasing score categories. The meta-analysis also showed an increased risk for those with a family history of liver cancer (relative risk = 2.55, 95% CI: 2.05-3.16). Family history of liver cancer was related to increased risk of liver cancer in Chinese population. This risk is particularly high for those with an affected mother. The "dose-response" of risk with an increasing family history score of liver cancer might further facilitate future cancer prevention programs on identifying individuals with the highest potential liver cancer risk.

Deregulation of signalling pathways in prognostic subtypes of hepatocellular carcinoma: novel insights from interspecies comparison

Hepatocellular carcinoma is a frequent and fatal disease. Recent researches on rodent models and human hepatocarcinogenesis contributed to unravel the molecular mechanisms of hepatocellular carcinoma dedifferentiation and progression, and allowed the discovery of several alterations underlying the deregulation of cell cycle and signalling pathways. This review provides an interpretive analysis of the results of these studies. Mounting evidence emphasises the role of up-regulation of RAS/ERK, P13K/AKT, IKK/NF-kB, WNT, TGF-ß, NOTCH, Hedgehog, and Hippo signalling pathways as well as of aberrant proteasomal activity in hepatocarcinogenesis. Signalling deregulation often occurs in preneoplastic stages of rodent and human hepatocarcinogenesis and progressively increases in carcinomas, being most pronounced in more aggressive tumours. Numerous changes in signalling cascades are involved in the deregulation of carbohydrate, lipid, and methionine metabolism, which play a role in the maintenance of the transformed phenotype. Recent studies on the role of microRNAs in signalling deregulation, and on the interplay between signalling pathways led to crucial achievements in the knowledge of the network of signalling cascades, essential for the development of adjuvant therapies of liver cancer. Furthermore, the analysis of the mechanisms involved in signalling deregulation allowed the identification of numerous putative prognostic markers and novel therapeutic targets of specific hepatocellular carcinoma subtypes associated with different biologic and clinical features. This is of prime importance for the selection of patient subgroups that are most likely to obtain clinical benefit and, hence, for successful development of targeted therapies for liver cancer.

Host genetic factors in hepatitis B infection, liver cancer and vaccination response: a review with a focus on Africa

The disease burden due to hepatitis B virus (HBV) infection remains significant; 350 million people are infected world-wide, and around half a million deaths each year are due to HBV-related liver disease and hepatocellular carcinoma (HCC). Infant immunisation against infection was introduced in the early 1980s, the vaccine is routinely administered across regions where the disease is endemic and has been shown to be safe and effective. However, the large number of older individuals with persistent infection means that disease will not be reduced significantly for several decades. Furthermore, failure to respond to the vaccination has been observed in about 5% of vaccinees and to date we have limited information on the durability of vaccine protection against infection. Hepatitis B infection and disease pathogenesis are known to be influenced by a number of factors including host genetics factors. This review aims to give an overview of the role of genetic variation in persistent HBV infection and the development of liver disease including HCC. Vaccine-induced immunity is, at least in part, heritable and we also discuss findings on the genetic control of responses to HBV vaccination. The epidemiology of HBV infection differs by world region, as does the genetic makeup of individuals originating from different regions. This review focuses on the situation in Africa, where hepatitis B is highly endemic.

Genetic variations at loci involved in the immune response are risk factors for hepatocellular carcinoma

Primary liver cancer is the third most common cause of cancer-related death worldwide, with a rising incidence in Western countries. Little is known about the genetic etiology of this disease. To identify genetic factors associated with hepatocellular carcinoma (HCC) and liver cirrhosis (LC), we conducted a comprehensive, genome-wide variation analysis in a population of unrelated Asian individuals. Copy number variation (CNV) and single nucleotide polymorphisms (SNPs) were assayed in peripheral blood with the high-density Affymetrix SNP6.0 microarray platform. We used a two-stage discovery and replication design to control for overfitting and to validate observed results. We identified a strong association with CNV at the T-cell receptor gamma and alpha loci (P < 1 × 10(-15)) in HCC cases when contrasted with controls. This variation appears to be somatic in origin, reflecting differences between T-cell receptor processing in lymphocytes from individuals with liver disease and healthy individuals that is not attributable to chronic hepatitis virus infection. Analysis of constitutional variation identified three susceptibility loci including the class II MHC complex, whose protein products present antigen to T-cell receptors and mediate immune surveillance. Statistical analysis of biologic networks identified variation in the "antigen presentation and processing" pathway as being highly significantly associated with HCC (P = 1 × 10(-11)). SNP analysis identified two variants whose allele frequencies differ significantly between HCC and LC. One of these (P = 1.74 × 10(-12)) lies in the PTEN homolog TPTE2.

CONCLUSION

Combined analysis of CNV, individual SNPs, and pathways suggest that HCC susceptibility is mediated by germline factors affecting the immune response and differences in T-cell receptor processing.

Risk of HCC: genetic heterogeneity and complex genetics

Hepatocellular carcinoma (HCC) is a common form of cancer that arises from hepatocytes and whose risk may be affected by several known environmental factors, including hepatitis viruses, alcohol, cigarette smoking, and others. Rare monogenic syndromes, such as alpha1-antitrypsin deficiency, glycogen storage disease type I, hemochromatosis, acute intermittent and cutanea tarda porphyria, as well as hereditary tyrosinemia type I are associated with a high risk of HCC. Several common conditions or diseases inherited as polygenic traits e.g. autoimmune hepatitis, type 2 diabetes, a family history of HCC, hypothyroidism, and non-alcoholic steatohepatitis also show an increased risk of HCC compared to the general population. Overall, the genetic susceptibility to HCC is characterized by a genetic heterogeneity; a high individual risk of HCC may thus be caused by several unlinked single gene defects, whose carriers are rare in the general population, or by more common conditions inherited by complex genetics.

Evidence for association with hepatocellular carcinoma at the PAPSS1 locus on chromosome 4q25 in a family-based study

A region on chromosome 4q25 has recently been highlighted as linked to hepatocellular carcinoma (HCC). In this study, we performed a family-based association analysis with 67 single-nucleotide polymorphisms (SNPs) to map this linkage region in 240 families with HCC, 212 (88.3%) of which were ascertained through hepatitis B virus surface antigen (HBsAg)-positive index cases. Individual SNP analysis with correction for multiple testing identified 10 SNPs in two correlated haplotype blocks, located in or around the 3'-phosphoadenosine 5'-phosphosulfate synthetase-1 (PAPSS1) gene (all P-values: <0.0075). Our linkage data and GIST (Genotype identity-by-descent sharing test) indicate that 6 of these 10 SNPs contributed to the linkage signal. The haplotype block of the strongest association with HCC extended from the intron 5 to the 3'-flanking region of PAPSS1; multiple consecutive three-SNP haplotypes in this region were significant. The most significant haplotype showed odd ratios of 3.41 (95% confidence interval (CI)=1.36-8.53) for homozygous individuals in a case-unaffected sibling analysis. This haplotype also revealed an association with elevated serum alpha-fetoprotein and with poor survival in familial cases and an independent series of HBsAg-positive cases with small tumor present at the time of hospital admission. These results implicate PAPSS1 as a candidate HCC-susceptibility gene in hepatitis B carriers.

Mutation analyses of integrated HBV genome in hepatitis B patients

Little has been learnt in the last 30 years about detection of HBV genome as well as its mutation analysis between hepatitis B fathers (HBF) and their children. In this study, we used nest polymerase chain reaction (PCR), fluorescence in situ hybridization (FISH), and DNA sequencing analysis, to examine the integrated HBV genome in paraffin-embedded testis tissues, which were taken as samples from HBF, and in peripheral blood mononuclear cells (PBMC) from 74 cases of HBFs and their children who were born after their fathers' HBV infection (caHBF). We found that HBV DNA existed in testis tissues, mainly in the basilar parts of the seminiferous tubules, and also in PBMC of HBF. It was also documented that there were point mutations of poly-loci, insertions and deletions of nucleotides in integrated HBV genomes, and the types of gene mutations in the HBFs were similar to those in caHBF. This study addresses the major types of gene mutations in integrated HBV genome in human patients and also presents reliable evidence of possible genetic transmission of hepatitis B.

Genetic control of resistance to hepatocarcinogenesis by the mouse Hpcr3 locus

The genome of the BALB/c mouse strain provides alleles that dominantly inhibit hepatocellular tumor development in F1 crosses with the highly hepatocarcinogenesis-susceptible C3H/He strain. Genome-wide linkage analysis using a 1536-single-nucleotide polymorphism array in a (C3H/He x BALB/c)F2 intercross population treated with urethane to induce hepatocellular tumor development revealed a locus with a major role in the resistance to hepatocarcinogenesis. This locus, designated hepatocarcinogen resistance 3 (Hpcr3) and mapping to central chromosome 15, showed a linkage at LOD score = 16.52 and accounted for 40% of the phenotypical variance. The BALB/c-derived allele at Hpcr3 reduced tumor-occupied area of the liver up to 25-fold, in a semidominant way. Additional minor loci were mapped to chromosomes 1, 10, and 18. A gene expression profile of normal adult mouse liver showed a significant association with susceptibility of BALB/c, C3H/He, and F1 mice to hepatocarcinogenesis and identified the genes expressed in the Hpcr3 locus region; moreover, this analysis implicated the E2F1 pathway in the modulation of the phenotype susceptibility to hepatocarcinogenesis.

CONCLUSION

These findings, indicating the complex genetics of dominant resistance to hepatocarcinogenesis, represent a step toward the identification of the genes underlying this phenotype.

Preoperative assessment of hepatocellular carcinoma tumor grade using needle biopsy: implications for transplant eligibility

OBJECTIVE

To examine the diagnostic agreement of preoperative needle core biopsy (NCB) grading of hepatocellular carcinoma (HCC) compared with the final surgical pathologic tumor grade.

SUMMARY BACKGROUND DATA

Some centers have adopted protocols for selecting patients with HCC for transplantation based on tumor grade as determined by preoperative NCB. The validity of NCB to predict final tumor grade has not been previously assessed.

METHODS

A total of 211 patients who underwent hepatic resection, open radiofrequency, or transplantation for HCC between 1998 and 2004 were identified. Clinicopathologic, NCB, and surgical data were collected and analyzed using chi and kappa statistics.

RESULTS

A total of 120 (67.4%) of the 178 who underwent resection or transplantation had an NCB. On preoperative NCB, the majority of HCC cases were classified as well-differentiated (n = 35; 37.6%) or moderately differentiated (n = 44; 47.3%), while 14 (15.1%) cases were categorized as poorly differentiated. In contrast, when tumor grading was based on the final surgical specimen, there was a significantly higher proportion of HCC cases graded as poorly differentiated (well-differentiated, n = 34; 36.6%; moderately differentiated, n = 33; 35.5%; poorly differentiated, n = 26; 27.9%) (P < 0.05). The overall percent agreement of NCB and surgical pathology to determine tumor grade was poor (kappa = 0.18, P < 0.0001). Whereas final pathologic tumor grade predicted the presence of microscopic vascular invasion (well, 15.7%; moderate; 31.9%, poor; 58.4%; P = 0.001), NCB grade did not (well, 23.7%; moderate, 28.0%; poor, 25.4%; P = 0.65).

CONCLUSIONS

Selection of candidates for transplantation based on NCB tumor grade may be misleading, as NCB tumor grade often did not correlate with grade or presence of microscopic vascular invasion on final pathology. Clinicomorphologic criteria (tumor size, number) should remain the major determinants of eligibility for transplantation.