Down Regulation of Jun Activation Domain-Binding Protein-1 Induces Cell Cycle Arrest and Apoptosis in a Human Parotid Gland Cancer Cell

Jun activation domain-binding protein-1 (Jab1) is a multifunctional protein that regulates cell proliferation, apoptosis and oncogenesis by interacting with and subsequently degrading a large number of proteins. Overexpression of Jab1 indicated the aggressiveness and a poor prognosis of some type of cancers. The antisense (AS) effect was confirmed in a cell line of adenocarcinoma parotid gland (HSY) that also exhibited overexpression of the protein. In the present study, the mechanism responsible for AS mediated cell cycles arrest and apoptosis of HSY cells was examined. The cell cycle arrest of Jab1 AS treated HSY cell was significantly increased when compared with that of control (SC) cells (Pless than0.05). Jab1 AS-treated cell induced apoptosis characterized by an increase in the activation of caspase-3 and -9. Furthermore, up-regulation of p27Kip1 was detected in Jab1 AS treated cells. These results suggest that Jab1 AS appears to induce cell cycle arrest and apoptosis in a HSY cell line, targeting this molecule could represent a promising new therapeutic approach for this type of cancer.