Experimental Therapeutic Investigations with 1-(Morpholinomethyl)-4-phthalimido-piperidindione-2,6 on Dimethylbenzanthracene-induced Tumors of Sprague-Dawley Rats Free

1-(Morpholinomethyl)-4-phthalimido-piperidindione-2,6 (CG 603) had a greater therapeutic effect than bilateral ovariectomy, estrogen (mestranol, 17α-ethinylestradiol-3-methylether), or androgen (drostanolone propionate, 2α-methyldihydrotestosterone propionate, 2α-MDTP) on 7,12-dimethylbenzanthracene-induced tumors in Sprague-Dawley rats. The antitumor activity of CG 603 was equivalent to hypophysectomy. Combined treatment with CG 603 and ovariectomy or estrogen gave no significant increase in antitumor activity over that with CG 603 alone. The combined treatment with CG 603 and 2α-MDTP showed a significantly higher regression of tumor weight and tumor number than the treatment with CG 603 or 2α-MDTP alone. While CG 603 in higher concentrations decreases the body weight of experimental animals, the combination of CG 603 in lower concentration with the anabolically acting 2α-MDTP increases the body weight of the treated animals. CG 603 probably exerts its antitumor activity primarily via endocrine pathways, and this is supported by endocrinologic studies.