title: Wild-type function of the p53 tumor suppressor protein is not required for apoptosis of mouse hepatoma cells.
abstract: The role of the tumor suppressor protein p53 in apoptosis of mouse hepatoma cells was studied. Different lines were used which were either p53 wild-type or carried various types of heterozygous or homozygous p53 mutations. The presence of mutations was demonstrated to correlate with a lack in transactivating activity of p53. While UV-light effectively produced apoptosis in cells of all lines, irrespective of their p53 mutational status, gamma-irradiation induced the formation of micronuclei but failed to induce apoptosis. Both UV- and gamma-irradiation led to nuclear accumulation and increases in p53 protein in p53 wild-type cells. Similarly, no significant differences in apoptotic response between p53 wild-type and p53 mutated cells were seen with other apoptotic stimuli like CD95/APO-1/Fas or TNFalpha. These data suggest that wild-type p53 is not required for induction of apoptosis in mouse hepatoma cells which may explain the apparent lack of p53 mutations in mouse liver tumors.
authors: Institute of Toxicology, University of Tübingen, Wilhelmstr. 56, 72074 Tübingen, Germany.
authors: C
authors: C
authors: Unger
authors: A
authors: A
authors: Buchmann
authors: C L
authors: CL
authors: Bünemann
authors: S
authors: S
authors: Kress
authors: M
authors: M
authors: Schwarz
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology* / Q000528:radiation effects; D006528:Carcinoma, Hepatocellular; D053938:DNA Fragmentation; D015972:Gene Expression Regulation, Neoplastic; D008099:Liver / Q000166:cytology; D051379:Mice; D018807:Polymorphism, Single-Stranded Conformational; D011518:Proto-Oncogene Proteins / Q000032:analysis; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D014162:Transfection; D014407:Tumor Cells, Cultured / Q000737:chemistry / Q000166:cytology; D016159:Tumor Suppressor Protein p53 / Q000032:analysis / Q000235:genetics*; D051028:bcl-2-Associated X Protein; D051020:bcl-X Protein; D019014:fas Receptor / Q000032:analysis / Q000235:genetics
chemical_list: C494812:Bcl2l1 protein, mouse; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; D051020:bcl-X Protein; D019014:fas Receptor