Abstract
A comparative study was made of the effects of the hormone hydrocortisone (Hy) on [rat] C6 glioma cells grown in monolayer and in suspension in cultures. Hy reversibly rendered c6 cells anchorage- and serum-dependent for their growth. In monolayer cultures, Hy inhibited cell cycle traversing exclusively at G1 phase. In agarose suspension, Hy blocked colony development. Hy-resistant variants were selected and isolated in agarose suspension. Examination of these variants showed that cells selected for Hy-resitance in suspension can be Hy sensitive when anchored to a solid substrate. Resistance to Hy in suspension and resistance to it in monolayer culture are apparently 2 independent phenotypes.