Hormone levels in serum. (A) Serum hormone levels after treatment. Serum samples (n = 4 to 5) were analyzed 15 to 22 days and 42 days after mice received an injection of vehicle (control), 5αP, or 3αHP. Data points represent nanograms per milliliter (mean ± SEM). (**P < 0.01 compared with respective controls). (B) Hormone levels in serum from 10 control (vehicle only) mice, six of which had developed tumors spontaneously (With tumor), and four that remained without tumors (No tumor). Hormone levels were determined with RIA and are presented as nanograms per milliliter 5αP, 3αHP, and progesterone (Pro) and (C) as the ratio of 5αP to 3αHP. *P < 0.05; **P < 0.01 for the comparison, as indicated or versus the levels in the "No tumor" mice.