SELENIUM INHIBITION OF DNA-SYNTHESIS IN MOUSE MAMMARY EPITHELIAL-CELL LINE YN-4

  • 1 January 1984
    • journal article
    • research article
    • Vol. 44  (10) , 4361-4365
Abstract
Previous results have documented that Na2SeO3 has a biphasic effect on the growth of mammary cells in vitro. The effects of Se on several parameters of cell proliferation in the YN-4 mouse mammary cell line were investigated. The biphasic effect of Se on cell growth was confirmed; i.e., 5 .times. 10-8 M Se stimulated cells growth, whereas 5 .times. 10-6 M delayed cell growth and 5 .times. 10-5 M was cytotoxic. The inhibition of cell growth by 5 .times. 10-6 Se was reversible when this dose was removed from the growth medium. The increased cell growth at 5 .times. 10-8 M Se was reflected by an increased cell number, increased uptake of [3H]thymidine into DNA, increased DNA labeling index and an increased rate of DNA synthesis. The decreased cell growth at 5 .times. 10-6 M Se was reflected by a decrease in all of these parameters of cell growth kinetics. The differential effects of Se were mainfested by 48 h after addition of S to the cell culture medium. One of the mechanisms of Se-mediated inhibition of carcinogenesis may be due to an inhibition of cell proliferation of responsive cells.