Background and aims. Various morphologies are seen in different salivary gland tumorsor within an individual
tumor, and the lesions show divers
biological behaviors. Experimental results support the hypothesis that increased CrkII proto-oncogene is associated with
cytokine-induced
tumor initiation and progression by altering cell motility signaling pathway. The aim of this study was to assess the CrkII expression in common malignant salivary gland
tumors and pleomorphic ade-
noma. Materials and methods. Immunohistochemical analysis of CrkII expression was performed on
paraffin blocks of 64 car-cinomas of salivary glands, 10
pleomorphic adenomas, and 10 normal salivary glands. Biopsies were subjected to immu-nostaining with EnVision detection system using monoclonal anti-CrkII. Evaluation of immunoreactivity of CrkII was based on the immunoreaction intensity and percentage of stained
tumor cells which were scored semi-quantitatively on a scale with four grades 0 to 3. Kruskal-wallis test and additional Mann-Whitney statistical test were used for analysis of CrkII expression levels. Results. Increased expression of CrkII was seen (P=0.005) in malignant
tumors including:
mucoepidermoid carcinoma,
adenoid cystic carcinoma, and
carcinoma ex
pleomorphic adenoma, but CrkII expression in
acinic cell carcinoma was weak. CrkII expression in
pleomorphic adenoma was weak or negative. A weak staining was sparsely seen in normal acinar serous cell. Conclusion. Increased expression of CrkII and its higher intensity of staining in
tumors with more aggressive
biologic behavior in
carcinomas of salivary gland is consistent with a role for this proto-oncogene in salivary gland
tumorigenesis and
cancer progression.