Abstract: Objective To investigate the different expressions and differential diagnosis values of HBD-3 in benign and malignant tumors and inflammation of salivary gland. Methods 87 cases of salivary gland benign tumor specimens, 35 cases of salivary gland malignant tumor specimens, 46 cases of inflammation specimens and 65 cases of normal salivary gland tissue specimens were selected from March 2009 to April 2014 in our hospital. The expressions of HBD3 protein in salivary gland tissues of different types of diseases were detected by SP immunohistochemistry. The expressions of HBD-3 mRNA in salivary gland tissues of different types of diseases were tested by RT-PCR. Results HBD-3 protein in salivary gland malignant tumor tissue showed low expression, which was found in the cytoplasm and nucleus, whereas in salivary gland benign tumor tissue and inflammatory tissues HBD-3 protein showed high expressions, which were expressed in the cytoplasm. The expression of HBD3 protein in salivary gland malignant tumor tissue was lower than the normal salivary gland tissue, while in salivary gland benign tumor tissue and inflammatory tissue the expressions were significantly higher than the normal salivary gland tissue, and the differences were statistically significant (P<0.05). Compared with normal salivary gland tissue, the relative expression of HBD-3 mRNA in salivary gland malignant tumor tissue significantly reduced, while in salivary gland benign tumor tissue and inflammatory tissue, the relative expression levels significantly increased, and the differences were statistically significant (P<0.05). Conclusion HBD-3 protein and gene in salivary gland benign tumor tissue and inflammatory tissue shows high expression, while in salivary gland malignant tumor tissue it shows low expression, and also appears nuclear transfer of protein expression. It might have some anti-tumor potential. 

Key words: salivary glands, β-defensin 3, tumor, inflammation, differential diagnosis