IN-VITRO AND IN-VIVO STUDIES OF MURINE SARCOMA-CELLS AFTER PROLONGED TREATMENT WITH PROMOTING PHORBOL ESTER TPA

Murine sarcoma cell line (L-1) treated with promoting phorbol ester (T PA) showed decreased content and activity of protein kinase C (PKC) as measured by Western blotting and histone phosphorylation methods. The PKC depleted line (L-1R) produced bigger, tumors after s.c. transplan tation into syngeneic mice and more spontaneous and artificial metasta ses developing after i.v. injection of tumor cells. The in vitro studi es revealed decreased: adhesiveness, migratory and invasiveness proper ties of PKC depleted cells. Negative correlation between in vitro and in vivo studies were found.