INDUCTION OF TUMOR-SUPPRESSOR P21 PROTEIN BY KINASE INHIBITORS IN MCF-7 CELLS

The expression level of tumor suppressor p21 protein in response to pr otein kinase inhibitors was examined in MCF-7 cells. Both H7 (serine/t hreonine kinase inhibitor) and staurosporine (protein kinase C inhibit or) were able to induce p21 protein in a time- and dose-dependent mann er. Induction of p21 by H7 but not staurosporine required the inductio n of p53 protein. Induction of p21 was preceded by the induction of p5 3 protein. Based on FAGS analysis, both H7 and staurosporine act as an timitogenic agents. (C) 1995 Academic Press, Inc.