Grubbs C J, Peckham J C, McDonough K D
Carcinogenesis. 1983;4(4):495-7. doi: 10.1093/carcin/4.4.495.
The concomitant administration of 20 micrograms 17 beta-estradiol and 4 mg progesterone/injection (5 days/week) over a 40-day treatment period beginning 10 days after methylnitrosourea (MNU) treatment was as effective as ovariectomy in inhibiting mammary cancers (an 84% reduction from non-hormone treated rats). The primary action of the hormones must have been directed at preneoplastic cells since the hormones were not given until 10 days after MNU (a direct-acting carcinogen with a short half-life).
在甲基亚硝基脲（MNU）处理10天后开始的40天治疗期内，每周5天同时给予20微克17β-雌二醇和4毫克孕酮/注射，在抑制乳腺癌方面与卵巢切除术效果相同（与未接受激素治疗的大鼠相比减少了84%）。激素的主要作用必定是针对癌前细胞，因为直到MNU处理10天后（MNU是一种半衰期短的直接作用致癌物）才给予激素。
