ACTIVATION BUT NOT INACTIVATION OF THE MTSI GENE IS ASSOCIATED WITH PRIMARY COLORECTAL CARCINOMAS

Several investigators have reported that alterations of the multiple t umor suppressor 1 (MTS1) gene frequently occurred in certain types of tumors. We examined the expression levels and somatic mutations of the MTS1 gene in primary colorectal carcinomas. The MTS1 transcript was q uantitatively detected in 14 of 17 tumors, but in only one case of adj acent normal mucosa. Direct sequencing of the amplified MTS1 gene show ed no somatic mutation in 17 primary colorectal carcinomas. These resu lts indicate that inactivation of the MTS1 gene is not involved in pat hogenesis of primary colorectal carcinomas, and that its enhanced expr ession is, instead, associated with primary colorectal carcinomas, esp ecially markedly in the early stage of tumor progression. (C) 1996 Aca demic Press, Inc.