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

Search MEDLINE/PubMed


  • Title: X-ray-induced changes in gene expression in normal and oncogene-transformed rat cell lines.
    Author: Lambert M, Borek C.
    Journal: J Natl Cancer Inst; 1988 Nov 16; 80(18):1492-7. PubMed ID: 2903253.
    Abstract:
    As an approach to identifying specific cellular markers for the cytotoxic action of x rays in mammalian cells, we used the QUEST system of high-resolution, two-dimensional protein gel electrophoresis and a computerized data base on proteins to score quantitative changes in patterns of protein synthesis. We measured the responses elicited after x irradiation of cells from the normal rat cell line REF52 as well as two oncogene-transformed REF52 cell lines with E1a or E1a plus the mutated c-Harvey-ras T24 (HRAS1 T24) allele. The transformed cell lines differed substantially in the patterns of changes in protein synthesis seen immediately after DNA damage. In addition, we identified a specific subset of growth-regulated cellular polypeptides that are correlated with the observed increase in x-ray-induced cell killing in the transformed cell lines. One of these polypeptides was cyclin (proliferating-cell nuclear antigen), a cell-cycle-specific DNA polymerase delta auxiliary factor. Synthesis of this set of coregulated polypeptides was rapidly suppressed by x irradiation in normal REF52 cells only. The inability of x irradiation to induce suppression of protein synthesis in cells from the transformed cell lines correlated with the increased susceptibility to x-ray-induced cell killing. This finding suggests that the cellular processes that underlie regulation of DNA-damage-induced growth arrest at the level of replicative elongation plays a role in determining the survival of x-irradiated cells.
    [Abstract] [Full Text] [Related] [New Search]