Expression of somatostatin type 2A receptor correlates with estrogen receptor in human breast carcinoma

Somatostatin type 2A receptor (sstr2A) has been shown to be directly involv ed in the transduction of antiproliferative effects and also to be the most predominant sstr subtype in human normal breast epithelium, as well as in human breast carcinoma. We investigated the immunoreactivity of sstr2A in 3 4 cases of human breast carcinoma and correlated these findings with the im munoreactivity of the estrogen receptor (ER), epidermal growth factor recep tor (EGFR), transforming growth factor a (TG Fa) and insulin like growth fa ctor I (IGF-I). We detected sstr2A immunoreactivity in normal mammary tissu e, and in 27 of 34 (79%) breast carcinomas. The sstr2A immunoreactivity was localized on the cellular membrane, however, weak cytoplasmic immunoreacti vity was also observed. Sstr2A immunoreactivity was heterogenously distribu ted in the whole tumor section. There was a statistically significant corre lation between sstr2A and ER immunoreactivity in the same tumor. No statist ically significant correlation was found between sstr2A immunoreactivity an d immunoreactivity for EGFR, TGF alpha and IGF-I or the patients' age.