Distinct experimental efficacy of anti-Fas/APO-1/CD95 receptor antibody inhuman tumors

Ligation of the Fas receptor (FasR) is a key step in apoptosis induction. U sing a series of human tumor cells (SNB19, SNB79,143N2, and SHEP), we obser ved a distinct efficacy of human anti-FasR antibody with an apparent correl ation with Fas cell surface antigen expression. In contrast, all cells stud ied expressed detectable FasR mRNA transcripts. For all anti-FasR antibody- sensitive tumor cells, we showed a similar efficacy of Mab according to dos e fractionation and injection site. We showed that, when injected into nude mice bearing human osteosarcoma 143N2, neuro. blastoma SHEP, prostatic can cer PAC120, and the two glioblastomas SNB19 and SNB79, anti-FasR Mab induce s significant inhibition of the growth rate of 143N2, SHEP, and PAC120 tumo rs, but has no efficacy on SNB19 and SNB79 tumors, with a relationship betw een in vitro and in vivo sensitivity to anti-FasR antibody. Altogether, the se results suggest the antitumor potential of anti-FasR antibody in human n eoplasms. (C) 2001 Academic Press.