Growth hormone and adrenocortical hormones in relation to experimental tumors; a review.

There is a vast literature on the influence of sex hormones and gonadotrophins on the incidence and growth of tumors, particularly those of the gonads and accessory sex organs. Less attention has been paid to the possible influence on tumors of other hormones, although aspects of the field now surveyed have been reviewed elsewhere (74, 76, 115, 150). There is some justification for considering adrenocorticotrophin (ACTH) and adrenocortical hor mones conjointly with growth hormone (GH, sometimes unnecessarily called somatotrophin or STH). This will be evident from the following sur vey of metabolic actions of these hormones in ani mals without tumors. For a fuller treatment of metabolic aspects and of the chemical nature of the hormones, reference may be made to other re views (e.g., 45, 80, 112, 118, 114, 117, 146, 180). With regard to chemical aspects, GH as iso lated from bovine pituitary glands is a protein with a molecular weight of about 47,000. Until re cently ACTH was considered to be a protein with a molecular weight of about 20,000. It now ap pears that a peptide constituent present in ACTH protein preparations is responsible for their activ ity in the Sayers test (lowering of adrenal ascorbic acid) and for some, if not all, of the other activities attributed to ACTH preparations. Until pituitary hormones can be isolated from blood, there must remain some uncertainty (cf. 102) as to the nature of GH and ACTH as actually secreted by the pituitary. This question is now approaching solution in the