You are not currently logged in.
Access your personal account or get JSTOR access through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Chemical Carcinogen-Mouse Mammary Tumor Virus Interactions in Cell Transformation
David K. Howard, Jeffrey Schlom and Paul B. Fisher
Vol. 19, No. 1 (Jan., 1983), pp. 58-66
Published by: Society for In Vitro Biology
Stable URL: http://www.jstor.org/stable/4292641
Page Count: 9
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
We have studied the process of mammary cell transformation in vitro using a single cell clone (Clone 18) from a presumptive epithelial cell line, C57MG, derived from a normal mammary gland; a mouse mammary tumor virus (MMTV) host-range variant (RIII)vp4; and the potent initiating carcinogen 7,12-dimethylbenz(a)anthracene (DMBA). After several serial subcultures, cells treated with virus and then with carcinogen exhibited an altered (transformed) morphology, a dramatic increase in anchorage independence, an increase in multinucleation after exposure to cytochalasin B, an enhanced ability to proliferate in low Ca2+ (0.01 mM) medium, and tumorigenicity when inoculated sub-cutaneously into athymic (nude) mice. Although some of these phenotypic alterations were observed also in cultures treated singly with MMTV or DMBA and in cultures exposed to DMBA before infection with MMTV, enhanced cytochalasin B multinucleation and tumorigenicity were properties observed only in mass cultures of cloned cells first infected with MMTV and then exposed to DMBA. This demonstrates for the first time that exposure of presumptive mammary epithelial cells to MMTV followed by DMBA, but not to either agent alone or to DMBA followed by MMTV, results in malignant transformation of these cells.
In Vitro © 1983 Society for In Vitro Biology