Tumour calcitonin. Interaction with specific calcitonin receptors.
The human epidermoid bronchial carcinoma (BEN) cell line has been shown to have specific membrane binding sites for calcitonin and to secrete high-molecular-weight forms (ranging from 40000 to 10000) of immunoreactive calcitonin. Synthetic salmon and human calcitonins and a thyroid extract of porcine calcitonin have been shown to displace 125I-labelled salmon calcitonin from the receptors in a dose-related fashion. The binding to these receptors of calcitonins derived from the BEN cell line and a medullary thyroid carcinoma with molecular weights ranging from 28000 to 3500 (both separated by gel-filtration chromatography) has been investigated. Neither major peaks of BEN-cell-line calcitonin showed receptor binding activity. Only one form of medullary thyroid carcinoma calcitonin, that which co-eluted with synthetic calcitonin monomer on gel-filtration chromatography, caused any significant displacement of labelled hormone from the receptors.
D000818:Animals; D001984:Bronchial Neoplasms / Q000378:metabolism*; D002116:Calcitonin / Q000276:immunology / Q000378:metabolism*; D002294:Carcinoma, Squamous Cell / Q000378:metabolism*; D002460:Cell Line; D002850:Chromatography, Gel; D006801:Humans; D018003:Receptors, Calcitonin; D011956:Receptors, Cell Surface / Q000378:metabolism*; D012474:Salmon; D013552:Swine; D013964:Thyroid Neoplasms / Q000378:metabolism
D018003:Receptors, Calcitonin; D011956:Receptors, Cell Surface; D002116:Calcitonin