Antiestrogens sensitize human ovarian and lung carcinomas for lysis by autologous killer cells

Background The antiestrogens tamoxifen (TX) and toremefine (TO) were shown previously to enhance the lysis of target cells by natural killer cells (NK ), lymphokine activated killer (LAK) cells, and by cytotoxic T lymphocytes (CTL). Materials and Methods. CTL were cultured from lung cancer tissue and from ascites fluid of ovarian carcinoma patients with the aid of human rec ombinant interleukin-2 (hrIL-2). The target, effector or both cell populati ons were pretreated by TX, TO and/or with human recombinant interferon-alph a (IFN-alpha). Results. Significant enhancement of cytotoxicity occurred wh en the tumor targets or both the target and effector cells were treated wit h TX, TO or when these drugs were used in combination with IFN-alpha. The l yric activity of CTL cultured from draining lymph nodes of lung cancer pati ents, was also observed after similar treatment. The lyric effect of autolo gous LAK; cells derived from peripheral blood was increased to a lesser ext ent, which could be amplified by additional treatment with IFN-alpha. Concl usions. The antiestrogens TX and TO and IFN-alpha enhance the lysis of auto logous tumor cells by CTL and LAK effectors.