The Significance And Relationships Between P16,P15 And TGF β1 Expressions In Salivary Gland Mucoepidermoid Carcinoma

Objective: To study the role and clinical significance of expressions of P16, P15 and TGF 1 during the carcinogenesis and development of mucoepidermoid carcinoma (MEC). Methods: The expression of p16,P15 and TGF 1 protein in 10 cases of normal salivary gland tissues and 45 cases of MEC was detected by the streptavidin-peroxidase (S-P) immunohistochemical method. Results: The positive rate of P16 and P15 in normal salivary gland tissues was 100% which was significantly higher than in MEC (62.2%, 73.3%)(P<0.05). As the differentiated degree of carcinoma was decreasing, The positive rate of P16 and P15 increased in MEC (P<0.05). P16 oncoprotein positive staining was found in 17/21 (80.9%) of well differentiated tumors, 10/18(55.6%) of moderately differentiated tumors and 1/6 (16.7%) of poorly differentiated tumors. P15 oncoprotein positive staining was found in 19/21 (90.5%) of well differentiated tumors, 13/18(72.2%) of moderately differentiated and 1/6 (16.7%) of poorly differentiated tumors. The expression of P16 was related to the lymph node metastasis in MEC (p<0.05), but not related to other clinical pathological factors (P>0.05). There were no relationships with P15 and clinical pathological factors (P>0.05). The positive expression of TGF 1 was not related to tumor grade and clinical pathological factors (P>0.05). There were close correlation between P16 and P15, P15 and TGF 1 in expression (P<0.05), but not correlation between P16 and TGF 1(P>.05). Conclusions: The abnormal expressions of P16 and P15 are closely correlated with the process of carcinogenesis of MEC. Comprehensive analysis of P16 and P15 will assistin determing the malignant degrees of MEC and predicting the tendency of regional lymph metastasis. The high expression of TGF 1 might relate to the malignant biological behavior of MEC.