ATG5 and central nervous system cancer: Radiation (10 Gy) on glioma cell lines on days 3 and 5 induced autophagy prior to apoptosis, while atg5-knockdown in U373 and LN229 glioma cells after radiation significantly decreased both autophagy and apoptosis, independently of caspase activation, suggesting that atg5 is required for apoptosis induction [151].