EFFECT OF TUMOR PROMOTER PHORBOL ESTERS ON THE INVITRO KERATINIZATION OF RAT EPIDERMAL-CELLS IN NORMAL, PREMALIGNANT AND MALIGNANT STAGES

  • 1 January 1981
    • journal article
    • research article
    • Vol. 72  (1) , 123-131
Abstract
The effects of a skin tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA), and related phorbol esters on primary diploid and 4 established, i.e., 2 aneuploid premalignant and 2 malignant, lines of fetal rat epidermal cells were analyzed. TPA quantitatively or qualitatively affected the keratinization processes of cultured epidermal cells in the concentration range of 10-1000 ng/ml. Its inhibitory effect on keratinization was obvious in the lamellar keratinization processes of aneuploid premalignant epidermal cells. With a few exceptions, the inhibition was reversible. TPA lethally damaged the primary diploid epidermal cells in this range of concentration. TPA did not inhibit the keratinization of malignant epidermal cells but destroyed the polarity in their keratinization processes.