Resistance to p53-mediated growth suppression in human ovarian cancer cells retain endogenous wild-type p53

Anticancer Res. 2002 Mar-Apr;22(2A):659-64.

Abstract

Cancer cells containing mutated p53 are sensitive to the re-introduction of the wild-type (wt) p53. We sought to determine whether ovarian cancer cells that retain wt p53 are sensitive to the re-introduction of wt p53. Our results demonstrated that A2780 and PA-1 cells, which retain wt p53, are more resistant to apoptosis and growth suppression induced by exogenous expression of wt p53 than SKOV-3 and Caov-3 cells that contain mutated p53. All cell lines, except PA-1, showed induction of the p53-targeted genes. Further, inhibitors of p53-dependent apoptosis, mdm2 and Bcl-xL were not overexpressed in A2780 and PA-1 cells. These results suggest that one major defect in PA-1 cells is due to abrogation of induction of the p53-targets which is independent of mdm2 and Bcl-xL. Although A2780 cells showed induction of the p53-targeted genes, the cleavage of caspase-9 was undetectable. Therefore, p53-dependent apoptosis may be blocked upstream or at the caspase-9 level in A2780 cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviridae / genetics
  • Apoptosis / genetics
  • Caspases / biosynthesis
  • Caspases / genetics
  • Cell Division / genetics
  • Cell Division / physiology
  • Female
  • Gene Expression Regulation, Neoplastic / genetics
  • Genes, p53
  • Genetic Therapy / methods
  • Genetic Vectors / genetics
  • Humans
  • Mutation
  • Nuclear Proteins*
  • Ovarian Neoplasms / genetics
  • Ovarian Neoplasms / metabolism
  • Ovarian Neoplasms / pathology*
  • Proto-Oncogene Proteins / biosynthesis
  • Proto-Oncogene Proteins / genetics
  • Proto-Oncogene Proteins c-bcl-2 / biosynthesis
  • Proto-Oncogene Proteins c-bcl-2 / genetics
  • Proto-Oncogene Proteins c-mdm2
  • Transfection
  • Tumor Cells, Cultured
  • Tumor Suppressor Protein p53 / antagonists & inhibitors
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / physiology*
  • bcl-X Protein

Substances

  • BCL2L1 protein, human
  • Nuclear Proteins
  • Proto-Oncogene Proteins
  • Proto-Oncogene Proteins c-bcl-2
  • Tumor Suppressor Protein p53
  • bcl-X Protein
  • MDM2 protein, human
  • Proto-Oncogene Proteins c-mdm2
  • Caspases