Accession Number : ADA320019

Title :   Radiation-Induced Apoptosis in Breast Cancer Cells.

Descriptive Note : Annual rept. 29 Aug 95-28 Aug 96,

Corporate Author : MASSACHUSETTS GENERAL HOSPITAL BOSTON

Personal Author(s) : Held, Kathryn D.

PDF Url : ADA320019

Report Date : SEP 1996

Pagination or Media Count : 15

Abstract : This project is designed to investigate the possible role of apoptosis as a mode of cell death in irradiated and tamoxifen-treated breast cancer cells and to study the potential for using these manipulations to enhance cell killing and, thus, improve radiation therapy of breast cancer. To date, six human breast cancer cell lines and nine human non-breast cancer lines have been treated in vitro with ionizing radiation or tamoxifen, and the ability of the cells to undergo apoptosis has been evaluated using gel electrophoresis. None of the breast lines and only three of the other lines show radiation-induced apoptosis with this assay. Expression of p53 and bcl-2 has been investigated in most of the lines. Studies with four breast cancer lines have shown that high dose tamoxifen or estradiol slows growth or causes cell death, and in the two lines studied to date this treatment increases radiation sensitivity. These data suggest that breast cancer cells may contain strong anti-apoptotic mechanisms or have lost the ability to undergo apoptosis, perhaps as part of their neoplastic development. In the next year we will confirm and extend these observations and continue to investigate possible mechanisms for this apparent resistance to apoptosis, with emphasis on p53, bcl-2 and related genes.

Descriptors :   *CELLS(BIOLOGY), *IONIZING RADIATION, *RADIOTHERAPY, *BREAST CANCER, RADIATION, NEOPLASMS, SENSITIVITY, DOSAGE, GENES, DEATH, ELECTROPHORESIS, RESISTANCE(BIOLOGY).

Subject Categories : Anatomy and Physiology
      Medicine and Medical Research

Distribution Statement : APPROVED FOR PUBLIC RELEASE