kappa-opioid receptor binding varies inversely with tumor grade in human gliomas

BACKGROUND, Opioid agonists can inhibit cell proliferation in various neura l tumor cell lines, including rat gliomas. Because opioid antimitogenic eff ects are mediated by opioid receptors, it was of interest to the authors to determine opioid receptor levels in human brain tumors. METHODS. Specimens obtained at craniotomy from 30 patients with glioma and nonneoplastic brain disorders were evaluated for their kappa-opioid recepto r binding. K-d and B-max values were estimated from homologous competition binding curves with the kappa(1)-selective radioligand [H-3]U69,593. RESULTS, Receptor binding density was greatest in nonneoplastic brain tissu e, less in Grade 2 and 3 astrocytoma, and least in glioblastoma multiforme. CONCLUSIONS. These results suggest that opioid receptor-based stratificatio n of grade may have clinical utility in distinguishing glioblastoma multifo rme from lower grade astrocytomas, and thereby may facilitate diagnosis and treatment. Cancer 1998;83:2561-6, (C) 1998 American Cancer Society.