Analysis of Cell Cycle Regulators and Extracellular Matrices Associated with Cell Proliferation in Salivary Gland Tumors

点击翻译按钮获取中文摘要

1. In ACCs, among various cell cycle regulators, the reduced expression of p27 was most closely related with development and progression and it can be a good indicator for predicting metastasis and poor survival. It was indicated that increased proteasome-mediated degradation after translation may play an important role in the reduction of p27 expression on the basis of the examination using ACC cell lines in vitro. Inhibition of proteasome-mediated degradation of p27 protein may be used as a possible target of a novel therapy for ACC patients.2. Bcl-2 and bax were expressed with varying intensity in salivary gland tumors. Bcl-2 was intensely expressed in acinic cell carcinomas with low proliferative activity, suggesting that the inhibition of apoptosis of tumor cells may play an important role in the tumor progression. On the other hand, poorly differentiated mucoepidermoid carcinoma with high proliferative activity expressed bax more intensely than bcl-2. The promotion of apoplosis a … More nd proliferation may simultaneously occur in such highly proliferative tumors.3.1) Various glycosaminoglycans (GAGs) were present at the small intercellular spaces in epithelial areas as well as in myxoid or chondroid areas in PAs, suggesting their production and secretion by the parenchymal cells. Heparan sulfate(HS) was intensely revealed in the nuclei in the chondroid and some epithelial cells and absent from tumor matrices, but other GAGs were only present in the extracellular matrices(ECM). These findings suggest that HS may be mainly related to modulating cell growth and differentiation rather than contributing to ECM constitution.2) Biglycan and aggrecan were contained in myxoid or chondroid matrices, although decorin and PG-M/versican were present in the true mesenchymal stroma. Aggrecan is a major proteoglycan and may be produced mainly by neoplastic myoepithelial cells.3) It was revealed by immuno-electromicroscopic observations that GAGs and aggrecan are produced by the neoplastic myoepithelial cells. Less