Effects of topically potent glucocorticoids on human diploid fibroblasts in vitro.

A wide range of concentrations of both cortisol and a topically more potent synthetic derivative, fluocinolone acetonide, was found not to inhibit the growth of cultured human skin fibroblasts; fluocinolone acetonide produced a slight increase in the growth rate. Both steroids had a transient stimulatory effect on fibroblasts, promoting an earlier entry into the period DNA synthesis (S) which was also accompanied by a substantial increase in the length of S.