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HORMONE RECEPTORS AND CYCLIC NUCLEOTIDE METABOLISM IN CANCER CELLS
Author(s) -
MARTIN T. J.,
HUNT N. H.,
BOYD HELEN,
ELLISON MORAG,
MICHELANGELI V. P.,
ATKINS D.
Publication year - 1976
Publication title -
clinical endocrinology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.055
H-Index - 147
eISSN - 1365-2265
pISSN - 0300-0664
DOI - 10.1111/j.1365-2265.1976.tb03846.x
Subject(s) - endocrinology , medicine , adenylate kinase , cyclase , parathyroid hormone , calcitonin , renal cortex , hormone , chemistry , biology , kidney , metabolism , receptor , stimulation , calcium
SUMMARY The possibility of a relationship between cyclic AMP formation and metabolic processes in tumours has been investigated. Changes in basal activity and hormone‐responsiveness of adenylate cyclase were demonstrated in plasma membranes and intact cells from pre‐cancerous liver of rats fed a diet containing the carcinogen 3′‐methyl‐4‐dimethylaminoazobenzene. Basal adenylate cyclase activity in hyperplastic parathyroid gland membranes was 200% higher than that in parathyroid adenoma membranes, corresponding with their relative rates of parathyroid hormone secretion in vitro . Membrane adenylate cyclase activity in hypernephromas was consistently 100–300% higher than in adjacent human renal cortex. Furthermore the adenylate cyclase activity of the tumour membranes was not influenced by a wide range of hormones which were effective stimulants in ‘normal’renal cortex membranes. Conversion of 25‐hydroxycholecalciferol to 1,25‐dihydrocholecalciferol could not be demonstrated in either hypernephroma or adjacent renal cortical tissue. However, three of the four hypernephromas tested secreted a bone‐resorbing factor. Cyclic AMP formation was increased by salmon, human and porcine calcitonins in both plasma membranes and intact cells from a poorly differentiated epidermoid cell carcinoma which was itself secreting calcitonin in culture. This phenomenon might be related to a feedback regulation of calcitonin production in this cell line. The observations are consistent with the concept of a relationship between cyclic AMP formation and certain metabolic functions (e.g. hormone production) in tumour cells.