title: Anti-tumour efficacy of calusterone against DMBA-induced rat mammary adenocarcinoma in vivo and in organ culture.
abstract: The effect of calusterone (7beta,17alpha-dimethyltestosterone) on rat mammary DMBA-induced adenocarcinoma was studied both in vivo and in organ culture. In vivo all 8 tumours with a diameter of less than 30 mm regressed following calusterone injection (10 mg/day for 2-3 weeks). In organ culture calusterone (20 mug/ml medium) inhibited the synthesis of DNA and RNA in all 7 cases examined. Testosterone also inhibited the synthesis of DNA and RNA in organ culture in 12 out of 14 and 10 out of 14 tumours respectively. Oestradiol-17beta on the other hand had no effect on DNA and RNA synthesis in organ culture although 70% of the tumours examined were ovarian dependent, i.e. regressed following castration. This could be explained by the direct effect of calusterone on rat adenocarcinoma compared with the indirect effect of oestradiol-17beta which probably exerts its action by activating the secretion of prolactin which acts on the tumour.
mesh_terms: D015127:9,10-Dimethyl-1,2-benzanthracene; D000230:Adenocarcinoma / Q000139:chemically induced* / Q000188:drug therapy*; D000818:Animals; D002369:Castration; D004273:DNA, Neoplasm / Q000096:biosynthesis; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced / Q000188:drug therapy*; D008777:Methyltestosterone / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use*; D009924:Organ Culture Techniques; D012334:RNA, Neoplasm / Q000096:biosynthesis; D051381:Rats; D011917:Rats, Inbred Lew; D013739:Testosterone / Q000494:pharmacology
chemical_list: D004273:DNA, Neoplasm; D012334:RNA, Neoplasm; D013739:Testosterone; D004958:Estradiol; D015127:9,10-Dimethyl-1,2-benzanthracene; D008777:Methyltestosterone