EFFECTS OF HUMAN RECOMBINANT ALPHA-2 ARG-INTERFERON AND GAMMA-INTERFERON ON HUMAN-BREAST CANCER CELL-LINES - DISSOCIATION OF ANTIPROLIFERATIVE ACTIVITY AND INDUCTION OF HLA-DR ANTIGEN EXPRESSION

  • 1 January 1985
    • journal article
    • research article
    • Vol. 45  (7) , 2957-2961
Abstract
Human recombinant .gamma.-interferon (rhu-IFN-.gamma.) and human recombinant .alpha.-interferon (rhu-IFN-.alpha.2 arg) with a chemical purity of over 95% were compared for their antiproliferative and HLA-DR-inducing activity in 5 human breast cancer cell lines (BT 20, ZR 75.1, MCF 7, 734B, Hs578T). Cytostatic effects on tumor cells were evaluated in monolayer cultures. HLA-DR antigen expression was examined by an indirect immunofluorescence technique using 2 different anti-HLA-DR monoclonal antibodies (anti-HLA-DR, VID-1) against framework determinants. rhu-IFN-.gamma. and rhu-IFN-.alpha.2 arg differed in their antiproliferative efficiency in terms of both dose dependency and the spectrum of sensitive target cells. Combinations of the rhu-IFN-.gamma. and rhu-IFN-.alpha.2 always resulted in higher cytostatic effects. HLA-DR expression was exclusively inducible by rhu-IFN-.gamma. and did not correspond to its antiproliferative activity. HLA-DR expression did not depend on proliferation but did require intact RNA and protein syntheses as shown by inhibition with cycloheximide and actinomycin D. HLA-DR antigen expression in mammary cancer lines was dependent on time, dose and the continued presence of rhu-IFN-.gamma.. In particular combinations type I and type II interferons might be useful in the treatment of breast cancer because they provide effective cytostatic and cell membrane-modulating properties.