Kallikrein-related peptidase 10 expression in salivary gland tissues and tumours

OBJECTIVES: Kallikrein-related peptidase 10 (KLK10) has been implicated in the development of several types of cancer. The purpose of this study was to analyze the expression of KLK10 in 3 types of salivary gland tumour and normal salivary glands. MATERIALS AND METHODS: A standard immunoperoxidase staining technique was used to assess the immunoexpression profile of KLK10 in normal salivary glands and 3 types of salivary gland tumour: pleomorphic adenoma, adenoid cystic carcinoma and mucoepidermoid carcinoma. RESULTS: Pleomorphic adenomas showed significantly lower KLK10 levels than control tissues. Neither of the malignant tumours (adenoid cystic carcinoma and mucoepidermoid carcinoma) showed a significant alteration in the immunoreactive scores of KLK10 in comparison with the normal salivary gland tissues. KLK10 immunoreactive scores were comparable in adenoid cystic carcinoma and mucoepidermoid carcinoma. Pleomorphic adenoma had significantly lower levels of KLK10 than mucoepidermoid carcinoma. CONCLUSIONS: The finding of lower KLK10 levels in pleomorphic adenoma suggests aberrant expression in a tumour that develops primarily from myoepithelial cells. A kallikrein cascade may play a role in the development and/or outcome of some salivary gland tumours.