Impact of Mitochondria-Mediated Apoptosis in U251 Cell Cycle Arrest in G1 Stage and Caspase Activation
Lei Zhang, Peng Liang, Rui Zhang
Department of Neurosurgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China (mainland)
Med Sci Monit 2015; 21:3629-3633
Most mitochondria-mediated apoptosis has some relevance to the cell cycle, but there is still a lack of investigations about U251 cell cycle in human brain glioma cells. In this study, we aimed to clarify the correlation of mitochondria-mediated apoptosis with the U251 cell cycle and its influence on apoptosis, through observing the impact of mitochondria-mediated apoptosis in U251cell specificity cycle arrest and Caspase activation.
MATERIAL AND METHODS: AnnexinV/PI and API were used to label the brain glioma cells for flow cytometry analysis of U251 cell apoptosis and cell cycle. RT-PCR and Western blot were performed to detect Caspase-3 and Caspase-9 activation.
RESULTS: Peripheral blood in stationary phase is not sensitive to apoptosis induction, but U251 cells have obvious apoptosis. Mitochondria-mediated apoptosis mainly occurs in the G1 phase of the cell cycle. Caspase-3 and Caspase-9 mRNAs and proteins expression increased significantly after the cells were treated by mitochondrial apoptosis-related gene Bax induction.
CONCLUSIONS: Mitochondria-mediated apoptosis is related to the U251 cell cycle with specific G1 stage arrest. Caspase activation occurs in the process of cell apoptosis.
Keywords: Brain Neoplasms - pathology, Apoptosis - physiology, Caspase Inhibitors - metabolism, Caspases - metabolism, Cell Line, Tumor, Cell Proliferation - physiology, G1 Phase Cell Cycle Checkpoints - physiology, Glioma - pathology, Mitochondria - physiology, Signal Transduction