EFFECT OF TRIPTORELIN (DECAPEPTYL(R)) COMBINED WITH HEPARIN ON ESTRADIOL LEVELS IN MCF-7 MAMMARY-CANCER CELLS AFTER INCUBATION WITH ESTRONESULFATE

The effects of triptorelin (Decapeptyl(R)) and heparin, alone or in co mbination, on the intracellular concentration of estradiol (E2) after incubation of estrone sulfate (E1S) with the MCF-7 mammary cancer cell s was investigated. Although heparin (10 mg/l culture medium) or Decap eptyl(R) (5 x 10(-7) or 5 x 10(-5) mol/l) did not affect the levels of radioactive E2 after incubation with [H-3]E1S, the combination of Dec apeptyl(R) and heparin significantly decreased the radioactive uptake and the intracellular concentrations of [H-3]E2. tn the absence of Dec apeptyl(R) and heparin incubations with E1S, the resulting E2 concentr ation (in nmol/kg DNA +/- SD) was 558 +/- 44; after heparin (10 mg/l) plus Decapeptyl(R) (5 x 10(-7) or 5 x 10(-5) mol/l) the values were 38 9 +/- 55 and 165 +/- 18, respectively. It is concluded that Decapeptyl (R) with heparin can decrease very significantly the conversion of E1S to E2 in MCF-7 cells, an observation that suggests new possibilities for the control of E2 in hormone-dependent breast cancer.