Differentiated expression of myosin VI in diverse human carcinomas

AIM: To investigate the expression profile of myosin VI in various human carcinomas and adjacent normal tissues. METHODS: A piece of cancer profiling array containing 154 matched cDNA pairs from 19 tumors and the adjacent normal tissues and 10 diverse tumor cell lines were separately hybridized with radiolabeled probes for myosin VI and housekeeping gene ubiquitin. Immunohistochemistry (IHC) was used to confirm the expression profile of myosin VI in 40 cases of ovarian adjacent normal tissues, 8 cases of cystadenoma, 16 cases of borderline tumors and 52 cases of endometrioid carcinoma by tissue microarray. RESULTS: Myosin VI was expressed in all the tissues and cell lines. The expression of myosin VI was significantly higher in ovarian and colon cancer tissues than that in matched normal tissues. The results of IHC confirmed that myosin VI expression rates were 100% (52/52), 81.3% (13/16) and 10.4% (5/48) in the ovarain carcinoma, boderline tumor and nomal ovarian epithelium or cystadenoma, respectively. The expression of myosin VI protein was significantly higher and stronger in ovarain carcinoma than that in the borderline tumor, benign tumor or normal ovary tissues. A significant correlation was also found between the expression of myosin VI and the tumor grade of ovarain carcinoma. CONCLUSION: Differentiated expression of myosin VI is found in diverse malignant tumor tissues and cell lines, suggesting myosin VI plays an important role in the tumor development and progression.