Racca S, Conti G, Crispino A, Gallo E, Di Carlo F
Chemioterapia. 1985 Jun;4(3):236-8.
Rats with DMBA-induced mammary tumors were treated for 30 days i.m. with medroxyprogesterone acetate (MPA) at doses of 7.5, 15 or 75 mg/kg. Complete regression (disappearance of tumor) was observed in 60% and 20% of tumors from rats treated with 75 or 15 mg/kg MPA respectively. Partial regression (50% decrease in tumor area) was found in the remaining 20% of tumors from rats treated with 15 mg/kg MPA. The dose of 7.5 mg/kg MPA resulted in being devoid of effectiveness. Estrogen receptor (ER) levels were significantly reduced at all doses of MPA injected both in responsive and non-responsive tumors. However, only tumors with ER levels above 15 fmol/mg before therapy resulted in being responsive to MPA treatment. Progesterone receptors were so reduced at the end of the experiment as to not be detectable in all treated groups. It was concluded that MPA is effective as an antitumoral drug also in DMBA-induced mammary tumors and that this effect is at least in part related to ER levels before treatment.
用二甲基苯并蒽（DMBA）诱导产生乳腺肿瘤的大鼠，通过肌肉注射醋酸甲羟孕酮（MPA），剂量分别为7.5、15或75mg/kg，持续治疗30天。分别用75mg/kg或15mg/kg MPA治疗的大鼠，其肿瘤中60%和20%出现完全消退（肿瘤消失）。在用15mg/kg MPA治疗的大鼠剩余20%的肿瘤中发现部分消退（肿瘤面积减少50%）。7.5mg/kg MPA剂量未产生效果。在注射所有剂量MPA的反应性和非反应性肿瘤中，雌激素受体（ER）水平均显著降低。然而，只有治疗前ER水平高于15fmol/mg的肿瘤对MPA治疗有反应。在实验结束时，所有治疗组的孕激素受体均降低至无法检测到的水平。得出的结论是，MPA在DMBA诱导的乳腺肿瘤中作为一种抗肿瘤药物也是有效的，并且这种作用至少部分与治疗前的ER水平有关。
