Influence of orchidectomy or oestrogen treatment on serum levels of pregnancy associated alpha 2-glycoprotein and sex hormone binding globulin in patients with prostatic cancer.

Peripheral serum levels of testosterone, immunoreactive oestrogens (E2), FSH, LH, prolactin and growth hormone (hGH) and two steroid-sensitive proteins, 'pregnancy-associated alpha 2-glycoprotein' (alpha 2-PAG) and sex hormone binding globulin (SHBG), were measured in patients with prostatic cancer before treatment and after orchidectomy or during combined oral and intramuscular oestrogen treatment. Following orchidectomy, the serum levels of testosterone and E2 decreased whilst the levels of FSH and LH increased significantly. No changes were noted in the serum levels of alpha 2-PAG, SHBG or prolactin. Oestrogen treatment significantly decreased the serum levels of testosterone, FSH and LH whilst levels of alpha 2-PAG, SHBG and prolactin were increased significantly. Serum levels of hGH during oestrogen treatment were significantly higher than in patients subjected to orchidectomy. These data are at variance with the established dogma of the oestrogen/androgen balance as a physiological regulator or liver protein synthesis, and indicate that factors other than the endogenous steroids may be operative. hGH may play an important role in this respect.