WESTERN-BLOT-ANALYSIS OF THYROTROPIN RECEPTOR EXPRESSION IN HUMAN THYROID-TUMORS AND CORRELATION WITH TSH-BINDING

Expression of thyrotropin receptor (TSHr) was analyzed in normal human thyroids and differentiated thyroid tumours by Northern blotting of t otal RNA and by Western blotting of detergent-solubilized membrane pro teins with an antibody specific for the extracellular domain of TSHr. Under nonreducing conditions TSHr stained as a 90-kDa protein in norma l thyroid tissue. Expression varied in differentiated carcinomas from normal to not detectable in parallel to steady state TSHr mRNA levels and TSH binding in a TSH binding assay. The negative expression of TSH r in some patients with differentiated carcinomas may have consequence s for the TSH suppressive treatments of these patients. (C) 1994 Acade mic Press, Inc.