The role of androgens in human normal and neoplastic bone tissues is still unclear. The paper presents data on metabolism of androgens in homogenates of malignant (osteosarcoma, chondrosarcoma, Ewing and giant cell) and benign primary tumors from 46 male and female patients aged 14-58 years. Using two substrates (testosterone and 5 alpha-dihydrotestosterone) for the first time are shown activities of main enzymes of androgen metabolism in all tumor types. 5 alpha-reductase activity was similar in all tumors, 3 alpha-hydroxysteroid dehydrogenase activity was the highest while that of 17 beta-hydroxysteroid dehydrogenase was the lowest. Unknown metabolite(s) of 5 alpha-dehydrotestosterone was discovered which may be hydroxy-metabolites of 5 alpha-androstane-3 beta, 17 beta-diol. A principal scheme of androgen metabolism in human neoplastic tissue is proposed.

17-Hydroxysteroid Dehydrogenases↗

PubMedDate not supplied

[Bone tumors and androgen metabolism].

The paper provides data of comparative assessment of activity of the key enzymes in metabolism of androgens in various morphological variants of sarcomas and benign bone tumors in 46 patients within the age range from 15 to 61, which were under treatment in the ORC named after N. N. Blokhin, RAMS, from 1996 to 1997. On the basis on publications and our own research results we can suggest that malignant human bone tumors of various histogenesis are subject to metabolic processes of testosterone (T), the principal androgen regulator in the bone tissue, as well as formation in bones of 5 alpha-dihydrotestosterone (DHT). One cannot exclude a possibility that metabolism of androgen in bone tissues is directed towards formation of other androgens (in addition to DHT), which may participate in the bone tissue regulation, for instance, 3 alpha- and 3 beta-diols; specific activity of the latter has recently been intensively scrutinized. One can expect that further research shall disclose the clinical significance of metabolism of androgens and of individual androgens in human bone formations.

Adolescent↗

PubMedDate not supplied

[Prognostic significance of p53, HER-2/neu, Ki-67 and VEGF expression in chondrosarcomas].

Expression of the mutant protein-suppressor of tumor growth p53 and the receptor of epidermal growth factor of type II--HER-2/neu may serve as prognostic factors for patients with chondrosarcoma of malignancy grade II. Combined expression of these proteins in the tumor tissue correlates with shorter 5-year survival of recurrence-free patients. The data obtained may be used for prognosis of chondrosarcoma course and choice of adequate therapy.

Adult↗