Mac-2 binding protein and galectin-3 expression in mucinous tumours of the ovary: An annealing control primer system and immunohistochemical study

Aim:We used a new differential display method, the annealing control primer ACP system, to analyse the differentially expressed genes in mucinous ovarian tumours. To verify the corresponding target gene, immunohistochemical staining was performed on various epithelial tumours of the ovary. Methods and Results: The ACP-based reverse transcriptase-polymerase chain reaction revealed that 21 genes were upregulated in the mucinous ovarian adenoma and 14 genes were upregulated in the mucinous ovarian carcinoma. Among them, we selected one upregulated gene, the Mac-2 binding protein Mac-2 BP, and verified the expression of the Mac-2 BP and its ligand, galectin-3, in a variety of epithelial ovarian tumours by immunohistochemistry. Positive expression of the Mac-2 BP was significantly higher in the mucinous ovarian tumours compared to the other epithelial tumours. Mac-2 BP expression was significantly increased in the borderline and malignant tumours compared to the benign tumours. Galectin-3 expression was more frequent in clear cell carcinomas, serous tumours and mucinous tumours than in endometrioid and transitional tumours. However, there were no differences in galectin-3 expression in comparisons among benign, borderline and malignant mucinous and serous tumours. Conclusion: These data indicate that the Mac-2 BP may play a role in the development and progression of mucinous ovarian tumours.