DEPDC1 Is A Noval Cell Cycle Related Gene That Regulates Mototic Progression

DEPDC1 is a recently identified novel tumor-related gene that is upregulated in several types of cancer and contributes to tumorigenesis. In the present study, we have investigated the expression pattern and functional implication of DEPDC1 during cell cycle progression. Expression study using synchronized cells demonstrated that DEPDC1 is highly expressed in mitotic phase of the cell cycle. Immunofluorescence assays further showed that DEPDC1 is predominantly localized in nucleus during interphase and is shuttled into cytoplasm upon exit from prophase during mitosis. Consistent with those observations, siRNA-mediated knockdown of DEPDC1 caused a significant mitotic arrest. Moreover, knockdown of DEPDC1 also resulted in remarkable mitotic defects such as abnormal multiple nuclei and multipolar spindle structure accompanied by the upregulation of A20 gene as well as several cell cycle-related genes such as CCNB1 and CCNB2. Taken together, our current observations strongly suggest that this novel cancerous gene, DEPDC1, has a pivotal role in the regulation of proper mitotic progression.