Somatostatin receptors in differentiated ovarian tumors

Published on Thursday, 30 July 2015


The presence of somatostatin receptors was investigated in 57 primary human ovarian tumors using in vitro receptor autoradiography with three different somatostatin radioligands, 125I-[Tyr11]-somatostatin-14, 125I-[Leu8, D-Trp22, Tyr25]-somatostatin-28, or 125I-[Tyr3]-SMS 201-995.

Three cases, all belonging to epithelial tumors, were receptor positive; specifically 1 of 42 adenocarcinomas, 1 of 3 borderline malignancies, and 1 of 2 cystadenomas. Four other epithelial tumors (3 fibroadenomas, 1 Brenner tumor), 4 sex cord-stromal tumors (2 fibrothecomas, 2 granulosa cell tumors), and 2 germ cell tumors (1 dysgerminoma, 1 teratoma) were receptor negative.

In the positive cases, the somatostatin receptors were localized on epithelial cells exclusively, were of high affinity (KD = 4.6 nmol/l [nanomolar]), and specific for somatostatin analogs. These receptors bound somatostatin-14 and somatostatin-28 radioligands with a higher affinity than the octapeptide [Tyr3]-SMS 201-995.

Healthy ovarian tissue had no somatostatin receptors.

A subpopulation of relatively well-differentiated ovarian tumors, therefore, was identified pathobiochemically on the basis of its somatostatin receptor content.

This small group of somatostatin receptor-positive tumors may be a target for in vivo diagnostic imaging with somatostatin ligands.



About this publication.


See also Somatostatin in oncology, the overlooked evidences.