These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Inverse correlation between RER+ status and p53 mutation in colorectal cancer cell lines.
    Author: Cottu PH, Muzeau F, Estreicher A, Fléjou JF, Iggo R, Thomas G, Hamelin R.
    Journal: Oncogene; 1996 Dec 19; 13(12):2727-30. PubMed ID: 9000147.
    Abstract:
    The high point mutation rate of replication error-prone (RER+) cells could theoretically lead to inactivation of the p53 gene by polyclonal mutations, which might explain the conflicting results that have been published on the p53 status of RER+ colon cancers. To address this issue, we tested the p53 status of 21 human colorectal cancer cell lines, including four showing microsatellite instability (RER+ phenotype). Denaturing gradient gel electrophoresis (DGGE) followed by sequencing showed that all four RER+ cell lines were wild type for p53 while 15 of the 17 RER- cell lines contained p53 mutations (P=0.001). Eight cell lines (four RER+ and four RER-) were analysed using three complementary methods to test more rigorously the polyclonal mutation hypothesis. (i) Of 87 single-cell clones (seven to 14 per cell line) examined by DGGE, only those derived from known p53 mutant cell lines showed altered profiles. (ii) Antibody DO-7 stained more than 80% of nuclei from the p53 mutant cell lines, but only 15% of nuclei from the RER+ cell lines. (iii) A yeast functional assay which can simultaneously detect polyclonal mutations at over 500 different sites in the p53 cDNA scored all four RER+ cell lines as containing only transcriptionally active p53. These data thus do not support the polyclonal mutation hypothesis and instead suggest that mismatch repair deficiency provides a p53-independent pathway for development of colorectal cancers.
    [Abstract] [Full Text] [Related] [New Search]