Further, the acid in these compartments helps to trap various environmental toxins away from the cytosol. Reducing the acid in these compartments may sensitize cells to these toxins thereby increasing the incidence of various cancers. In their follow-up study, the researchers detail the mechanisms by which tamoxifen affects the cell. They show that tamoxifen accumulates into the membranes that both surround cells and separate the compartments of a cell. Of greatest clinical significance is their demonstration that these actions of tamoxifen are independent of the cell's estrogen receptor.
Tamoxifen blocks the growth of breast tumors by interacting with the receptors for estrogen.
Thus, the researchers have developed a way to select for those drugs that should inhibit the growth of breast tumors in the absence of the other effects of tamoxifen. Individuals with breast cancer should seriously consult with their physician concerning the appropriateness of the drug for them. However, until variants are found that do not have these side-effects, I would recommend a more cautious approach for any healthy woman who is considering treatment with tamoxifen to prevent the development of breast cancer. Simon's co-authors on the paper are Yu Chen, B.S., at Rockefeller, and Melvin Schindler, Ph.D., at Michigan State University. This research was supported in part by the National Cancer Institute, part of the federal government's National Institutes of Health, by the American Cancer Society, and by the Wolfensohn, William and Helen Mazer, Pardee and Irving A. Hansen Memorial Foundations.