Effect of Steroids on Growth of Mouse Fibroblastsin Vitro

Abstract

Fibroblasts of Clone 929-L were incubated in medium containing various concentrations of cortisol, tetrahydrocortisol, 11-desoxycortisol, dexamethasone, prednisolone, fluocinolone acetonide and fluocinolone acetonide acetate. Growth curves constructed by counting cells on days 3, 5 and 7 after inoculation into roller tubes showed tetrahydrocortisol to be without growth-inhibitory action below 25 ng/ml, while 11-desoxycortisol inhibited growth at concentrations as low as 1 μg/ml. The order of increasing activity of the other compounds was cortisol, prednisolone, dexamethasone, fluocinolone acetonide and fluocinolone acetonide acetate, the last 2 still having significant growth-inhibitory activity at 0.00075 μg/ml. None of the other steroids studied had such activity at 0.001 μg/ml. Morphologic changes induced by these steroids included disintegration of cytoplasm and nucleus, and loss of cell processes. One of the steroids tested was also found to have growthenhancing effects, and was able to partly reverse the growth depression induced by cortisol. (Endocrinology76: 916, 1965)