The Ratio of Splicing Variants of MGC-24/CD164, a Sialomucin, Correlates with the Metastatic Potential of Colorectal Carcinomas

Abstract

MGC-24/CD164 is a sialomucin expressed in many normal and cancerous tissues. In humans, soluble and transmembrane forms of MGC-24 are produced by alternative splicing. The total MGC-24 RNA level was found to be lower in human colorectal carcinomas as compared with the adjacent normal mucosal tissues. Lower MGC-24 mRNA levels in colon carcinomas and in the adjacent normal mucosa epithelium correlate with lymphatic vessel invasion by the carcinoma. The ratio of the soluble form to the transmembrane form of the mRNA in colorectal carcinomas was determined by ribonuclease protection assay. Higher ratios were correlated with less venous invasion and less remote metastasis, which became evident during postoperative observation.