EVALUATION OF THE 5'-SPLICED FORM OF HUMAN CATHEPSIN-B MESSENGER-RNA IN COLORECTAL MUCOSA AND TUMORS

To evaluate the 5' spliced form of human cathepsin B mRNA in colorecta l mucosa and tumors, we have determined the ratio of the spliced form for the exon 2/the complete form of cathepsin B mRNAs obtained by RT-P CR. Such ratio is significantly higher in colorectal tumors than in co lorectal mucosa (p<0.05, Kruskal-Wallis test) or in skeletal muscle (p <0.05). Moreover, 2-fold more complete form than the spliced mRNA was found in the tumors than in the colorectal mucosa. Our data indicate t hat the alternative splicing of human cathepsin B mRNA in the 5'UTR ma y be considered as an indicator of the cellular transformation, in col orectal cancer.