This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Nair, B. K. Articles by DeOme, K. B. Search for Related Content PubMed PubMed Citation Articles by Nair, B. K. Articles by DeOme, K. B.

A Growth-stimulating Factor from Solid Mouse Mammary Tumors¹

Department of Zoology and its Cancer Research Laboratory, University of California, Berkeley, California 94720

A soluble fraction (SF) prepared from solid spontaneous primary mouse mammary tumors stimulated the growth of density-inhibited mouse embryo cells in monolayer culture. Dialysis of the SF increased its growth-stimulating activity. At higher concentrations, both nondialyzed and dialyzed SF's were inhibitory to cell growth. A similar preparation from normal mouse mammary gland showed some growth-stimulating activity. SF from the kidney of tumor-bearing or multiparous old mice showed high activity, while that from tumor-free virgin young mice did not show significant activity. Hyperplastic alveolar nodules of the mammary gland showed activity as high as that of tumors. The growth-stimulating factor in the SF was precipitated with 60% saturated ammonium sulfate, and the ammonium sulfate precipitate was further separated by Sephadex G-100 column chromatography.

¹ This work was supported by USPHS Grants CA-05388 and CA-05045 from the National Cancer Institute.

² Present address: Department of Community and Environmental Medicine, University of California, Irvine, College of Medicine, Irvine, Calif. 92664.

Received 6/ 1/73. Accepted 9/18/73.