EFFECTS OF NEW SOMATOSTATIN ANALOGS ON THE CELL-PROLIFERATION OF COLONIC CRYPTS AND COLONIC CANCERS IN RATS

The antiproliferative activity of two new somatostatin (SS) analogs: A SS-51 and ASS-52 have been tested in this study. We assessed their abi lity to inhibit the DNA synthesis in normal colon crypt cells and in t he cells of chemically (dimethylhydrazine)-induced colon cancer in the rats. The incorporation of bromodeoxyuridine (BrDU) into appropriate cell nuclei was used as an index of DNA synthesis. It was found that: 1) Only ASS-51 significantly decreases the colon crypt cell proliferat ion in the rat when compared to controls. Since both analogs were prev iously shown to inhibit GH release, these data indicate that the antip roliferogenic effect of ASS-51 is independent of the inhibition of GH release. 2) Both examined analogs did not significantly effect the BrD U incorporation into cell nuclei of chemically-induced colon cancer.