TELOMERASE AND CELL-PROLIFERATION IN MOUSE SKIN PAPILLOMAS

The progression of chemically induced mouse skin papillomas is paralle led by an increase in telomerase activity. In this study, we compared telomerase activity and rate of cell proliferation in papillomas obtai ned early versus late in papilloma progression. Eighteen early papillo mas (after 15 wk of promotion) showed no evidence of telomerase activi ty, and their average cell proliferation index was 26.6% +/- 6.3. On t he other hand, most of the papillomas harvested after 25 wk of promoti on showed high levels of telomerase activity, but their average cell p roliferation index (30.8% +/- 6.2) was not different from that of the early lesions. We concluded that there appears to be no association be tween the level of telomerase activity observed in mouse skin papillom as and the rate of cell proliferation of each individual tumor. Telome rase expression may indicate the existence of more abundant tumor subp opulations in advanced papillomas with proliferative potential for aut onomous growth. (C) 1997 Wiley-Liss, Inc.