Beta-catenin mutations and expression, 249serine p53 tumor suppressor gene mutation, and hepatitis B virus infection in southern African Blacks with hepatocellular carcinoma.
OBJECTIVE
To ascertain the prevalence of deregulating mutations of beta-catenin gene, and to correlate this with the occurrence of 249(serine) p53 gene mutation and hepatitis B virus infection in southern African Blacks with hepatocellular carcinoma.


METHODS
Paired cancer/non-cancerous liver tissues from 21 and cancer tissues alone from 20 Black Africans with hepatocellular carcinoma were studied. RT-PCR-SSCP and sequencing were used to detect mutations in exon 3 of the beta-catenin gene, and PCR, restriction endonuclease analysis, and sequencing to detect the p53 gene mutation. Immunostaining was used to identify beta-catenin protein expression in hepatocytes.


RESULTS
No mutations in exon 3 of the beta-catenin gene were found in tumor or non-tumorous tissues. Immunohistochemical staining showed beta-catenin protein expression in membranes and cytoplasm of hepatocytes but not in the nuclei. The 249serine p53 gene mutation was detected in 27.2% of the hepatocellular carcinoma tissues but not in non-cancerous tissues. No correlation was found between beta-catenin mutation and over-expression and 249serine p53 gene mutations or hepatitis B virus surface antigenemia.


CONCLUSIONS
Unlike hepatocellular carcinomas in China, Japan, and Europe, deregulating beta-catenin gene mutations do not appear to occur in southern African Blacks with this tumor and do not therefore interact with either the 249serine p53 gene mutation or hepatitis B virus infection in its pathogenesis.
Elmileik
Hashim
H
MRC/University Molecular Hepatology Research Unit, Department of Medicine, University of the Witwatersrand, Johannesburg, South Africa.
Paterson
Alan C
AC
Kew
Michael C
MC
D000353:Africa, Southern; D044383:Black People / Q000235:genetics*; D006528:Carcinoma, Hepatocellular / Q000235:genetics* / Q000503:physiopathology / Q000821:virology*; D003598:Cytoskeletal Proteins / Q000235:genetics*; D004252:DNA Mutational Analysis; D016158:Genes, p53; D006509:Hepatitis B / Q000150:complications*; D006801:Humans; D007150:Immunohistochemistry; D008113:Liver Neoplasms / Q000235:genetics* / Q000503:physiopathology / Q000821:virology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015534:Trans-Activators / Q000235:genetics*; D051176:beta Catenin
C495270:CTNNB1 protein, human; D003598:Cytoskeletal Proteins; D015534:Trans-Activators; D051176:beta Catenin