Radiation-induced autophagy is associated with LC3 and its inhibition sensitizes malignant glioma cells

• DOI: 10.3892/ijo.26.5.1401
• Publication Date: 2014-03-10T07:30:41Z
• Authors: Hideaki Ito; Shigeru Daido; Takao Kanzawa; Seiji Kondo; Yasuko Kondo
• Keywords: Autophagosome; Bafilomycin

Autophagy is a novel response of cancer cells to ionizing radiation (IR) or chemotherapy, but its significance mechanism remains largely elusive. characterized with the prominent formation autophagic vacuoles in cytoplasm. It protein degradation system that involves autophagic/lysosomal compartment. The process begins sequestering portion cytoplasm, forming autophagosome. autophagosome then fuses lysosome and lyses contents. To study radiation-induced autophagy specific molecules, we assessed changes expression microtubule-associated light chain 3 (LC3) intracellular distribution after IR comparison starvation-induced autophagy. First, showed induced cell cycle arrest autophagy, not apoptosis, human malignant glioma U373-MG cells. Type II LC3, specifically associated membrane autophagosome, increased amino acid starvation. Exogenous LC3 distributed on punctate structures, indicative autophagosomes. inhibitors, 3-methyladenine bafilomycin A1, radiosensitized Furthermore, γH2AX foci, show extent DNA double-strand breaks, were more pronounced prolonged treated inhibitors than those only. Our results suggest may represent new application radiosensitization for