REVERSIBLE INHIBITION OF NORMAL HUMAN PROKERATINOCYTE PROLIFERATION BY TYPE-BETA TRANSFORMING GROWTH FACTOR-GROWTH INHIBITOR IN SERUM-FREE MEDIUM

  • 1 April 1986
    • journal article
    • research article
    • Vol. 46  (4) , 2068-2071
Abstract
Type .beta. transforming growth factor-growth inhibitor (TGF.beta./GI) causes normal human prokeratinocytes to arrest growth predominantly in the G1 phase of the cell cycle within 48 h after log phase cultures are exposed to the factor in serum-free medium. The growth arrest induced by TGF.beta./GI is reversible because the cells from treated cultures can be replated into fresh medium and grown into large colonies. Normal prokeratinocytes are demonstrated to secrete TGF.beta./GI-like molecules into the culture medium and to have specific cell surface receptors for this molecule. In contrast, a human squamous cell carcinoma, SCC-25, does not arrest growth when exposed to TGF.beta./GI. These cells, unlike the normal prokeratinocytes, do not exhibit detectable cell surface receptors for the factor.