Antiproliferative effect of leuprorelin acetate, alone or combined with tamoxifen or medroxyprogesterone acetate, on human breast cancer cell lines.
We have investigated the antiproliferative action of leuprorelin acetate (TAP-144) on human breast cancer cells, cultured in medium supplemented with charcoal-treated fetal calf serum. The analogue had no effect on cell growth of oestrogen receptor-negative MDA-MB-231 cells. Although ineffective when used alone, TAP-144 inhibited in a dose-dependent fashion the oestradiol-induced cell growth in oestrogen receptor-positive and oestrogen-sensitive MCF-7, ZR-75-1 and CG-5 cells. TAP-144 did not modify the growth inhibitory activity of tamoxifen on CG-5 cells. A high concentration of TAP-144 (10(-6) M) seemed to increase the antioestrogenic effect of medroxyprogesterone acetate (MPA) (10(-7) M) in the same model. The data reported indicate that, in our culture conditions, TAP-144 has a direct antitumour effect on breast tumour cells. Our findings concerning the promotion of the antiproliferative effect of MPA merit further investigation.
Sica
G
G
Istituto di Istologia ed Embriologia, Università Cattolica del Sacro Cuore, Rome, Italy.
Iacopino
F
F
Marini
L
L
Robustelli della Cuna
G
G
D000970:Antineoplastic Agents / Q000494:pharmacology*; D001943:Breast Neoplasms / Q000188:drug therapy*; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D003692:Delayed-Action Preparations; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D006801:Humans; D016729:Leuprolide / Q000494:pharmacology*; D008525:Medroxyprogesterone / Q000031:analogs & derivatives* / Q000494:pharmacology; D017258:Medroxyprogesterone Acetate; D013629:Tamoxifen / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000187:drug effects
D000970:Antineoplastic Agents; D003692:Delayed-Action Preparations; D013629:Tamoxifen; D004958:Estradiol; D017258:Medroxyprogesterone Acetate; D016729:Leuprolide; D008525:Medroxyprogesterone