FAS-INDUCED CHANGES IN CDC2 AND CDK2 KINASE-ACTIVITY ARE NOT SUFFICIENT FOR TRIGGERING APOPTOSIS IN HUT-78 CELLS

Recent evidence suggested a role for the cell cycle dependent kinases cdc2 and cdk2 in apoptosis. An important mechanism by which many cell types could undergo apoptosis is through the activation of the Fas mol ecule on the cell membrane. To investigate whether Fas-induced cell de ath activated cdc2 and cdk2 kinases inappropriately, the human T lymph oma cells HUT-78, which express a high copy number of Fas, and two oth er previously characterized subclones of the same cell line which expr ess mutant, cell death-deficient dominant-negative forms of Fas, were Fas-challenged and the changes in cdc2 and cdk2 kinase activity monito red. In both wild-type and Fas-mutated HUT-78 cells, apoptosis was ass ociated simultaneously with decreased cdc2 and increased cdk2 activity . This association suggested that changes in cdc2 and cdk2 kinase acti vity are secondary events in cell death mediated by Fas. (C) 1997 Wile y-Liss, Inc.