Abnormal structure and expression of p53 gene in human hepatocellular carcinoma (hepatocarcinogenesis/recessive oncogene/gene expression)
Résumé
There is little information regarding the molecular mechanisms of hepatocarcinogenesis. We studied the p53 gene at the DNA, RNA, and protein level in seven human hepatocellular carcinoma (HCC)-derived cell lines; six of seven showed p53 abnormalities. By Southern blotting, the p53 gene was found to be partially deleted in Hep 3B and rearranged in SK-HEP-1 cells. Transcripts of the p53 gene were undetectable in Hep 3B as well as in FOCUS cells that had no apparent deletion or rearrangement of the p53 gene. Immunoprecipitation after [35Sjmethionine labeling of HCC cells demonstrated that p53 protein was absent in Hep 3B and FOCUS and reduced in concentration in PLC/PRF/5 cells. p53 synthesized by