ABSTRACT
<p><b>OBJECTIVE</b>To study the expression of inhibitor-1 of DNA binding/differentiation-1 (Id-1) and thrombospondin-1 (TSP-1) genes in mucoepidermoid carcinoma of different malignant degree and analyze the relationship between them.</p><p><b>METHODS</b>Using immunohistochemistry (IHC) staining technique, TSP-1 and Id-1 proteins in the mucoepidermoid carcinoma of different malignant degree, including well-differentiated, moderately differentiated and poorly differentiated mucoepidermoid carcinoma, and normal salivary gland tissues were detected.</p><p><b>RESULTS</b>The positive rate of Id-1 and TSP-1 in normal salivary glands were apparently lower than that in malignant mucoepidermoid carcinoma(P = 0.000, P = 0.013). The positive rate of Id-1 in moderately and poorly differentiated mucoepidermoid carcinoma was higher than that of the well-differentiated (P = 0.001, P = 0.002). However, the positive expression of Id-1 showed no relationship between the moderately and poorly differentiated mucoepidermoid carcinoma(P > 0.05). The positive rate of TSP-1 in poorly differentiated mucoepidermoid carcinoma was less than that of the well-differentiated(P = 0.014). The positive expression of TSP-1 showed no relationship between the moderately and poorly differentiated mucoepidermoid carcinoma(P > 0.05), and the positive expression of it also showed no relationship between the moderately and well differentiated mucoepidermoid carcinoma (P > 0.05). The expression of Id-1 and TSP-1 showed negative correlation(r = -0.394, P = 0.002).</p><p><b>CONCLUSION</b>The expression of TSP-1 may inhibit the development of the mucoepidermoid carcinoma, contrarily, the expression of Id-1 may prompt the development of the mucoepidermoid carcinoma. The expression of Id-1 and TSP-1 has negative correlation.</p>