Antiproliferative effects of somatostatin and the somatostatin analog SMS 201-995 on three human breast cancer cell lines.

The antiproliferative effect of somatostatin and the somatostatin analog SMS 201-995 on three human breast cancer cell lines (CG5, T 47 D, and ZR 75-1) is reported. Both peptides markedly inhibited CG5 cell growth with a maximal inhibition of about 40% as compared with control cells. The antiproliferative effect of somatostatin on T 47 D and ZR 75-1 cells was much less evident. These results suggest that somatostatin is a peptide inhibitory factor for human breast cancer cells. Possible therapeutic implications of these findings are still to be investigated.