Loss of asparagine synthetase suppresses the growth of human lung cancer cells by arresting cell cycle at G0/G1 phase.

The aim of this research is to determine the role of human asparagine synthetase (ASNS) in human lung cancer. In the present study, immunohistochemical staining and the Oncomine database mining showed that the expression of ASNS gene was higher in lung cancer tissues than that in the normal tissues by. In addition, western blot assay showed that ASNS was elevated in lung cancer A549 and 95D cell lines as compared with that in H1299 and H460 cells. Therefore, A549 and 95D cells were chosen for subsequent MTT and colony formation assay. It was found that knockdown of ASNS inhibited the growth and colony formation abilities of A549 and 95D cells. Flow cytometry showed that ASNS silencing arrested cell cycle progression at G0/G1 phase in A549 cells, probably through regulating the expression of cell cycle molecules such as CDK2 and Cyclin E1 as shown by quantitative real-time PCR. Taken together, our study indicates that ASNS may be an important target for lung cancer diagnosis and treatment.