A TRIAL TO KILL TUMOR-CELLS THROUGH FAS (CD95)-MEDIATED APOPTOSIS IN-VIVO

We tried to induce tumor cell death in vivo through Fas (CD95)-mediate d apoptosis. Murine hepatoma MH 134 (Fas(-)) was transfected with muri ne Fas antigen cDNA. Fas(+) F6b but not Fas(-) N1d cells underwent apo ptosis after treatment with anti-Fas antibody in vitro. The possibilit y of eradicating tumor cells in vivo with anti-Fas antibody was invest igated using double-mutant gld/gld lpr/lpr mice which lack both Fas li gand (Fast) and Fas to avoid cytotoxic activity of the antibody to the liver and interference from endogenous Fast. A single administration of anti-Fas antibody efficiently suppressed the growth of F6b tumors b ut not that of Nld tumors in these mice. Thus, the therapy with Fas-Fa sL system may be a promising approach for cancer treatment, and this m odel is useful for study on in vivo apoptosis-mediated antitumor activ ity. (C) 1996 Academic Press, Inc.