Nuclear hBD-1 accumulation in malignant salivary gland tumours

21 paraffin-embedded tissue samples of benign (n = 7), and malignant (n = 7) salivary gland tumours as well as healthy (n = 7) salivary glands were examined immunohistochemically for the expression of p53, bcl-2, and hBD-1, -2, -3.HBD-1 was distributed in the cytoplasm of healthy salivary glands and benign salivary gland tumours but seems to migrate into the nucleus of malignant salivary gland tumours. Pleomorphic adenomas showed cytoplasmic as well as weak nuclear hBD-1 staining.HBD-1, 2 and 3 are traceable in healthy salivary gland tissue as well as in benign and malignant salivary gland tumours. As hBD-1 is shifted from the cytoplasm to the nucleus in malignant salivary gland tumours, we hypothesize that it might play a role in the oncogenesis of these tumours. In pleomorphic adenomas hBD-1 might be connected to their biologic behaviour of recurrence and malignant transformation.The majority of salivary gland tumours are benign. Malignant salivary gland tumours are less frequent but occur in 15 to 32 percent of all patients. The most common point of origin for salivary gland tumours is the parotic gland in up to 80 percent of all cases [1].Salivary gland tumours show a variety of different morphologic features which complicate the exact histomorphological diagnosis. They might be subdivided into salivary gland tumours with a) myoepithelial components, b) basaloid components, c) epithelial components, d) lymphatic components and e) pleomorphic adenomas [2].In the investigation of the development of salivary gland tumours as well as in the prediction of their clinical course and possible treatment options, molecular biology has moved into the centre of tumour research. In this context proliferation associated antigens as Ki-67, proto-oncogenes as bcl-2, tumour suppressor genes as p53 or p21 and the overexpression of growth-factor binding receptors as HER-2 have been identified as important factors in the malignant progression of these tumours. [3].Defensines as hBD