title: Assessment of ER Stress and autophagy induced by ionizing radiation in both radiotherapy patients and ex vivo irradiated samples.
abstract: Acute radiation leads to several toxic clinical states and triggers some molecular pathways. To shed light on molecular mechanisms triggered by ionizing radiation (IR), we examined the expression profiles of endoplasmic reticulum (ER) stress and autophagy-related genes in individuals who were exposed to IR. Blood samples were collected from 50 cancer patients before radiotherapy and on the 5th, 15th, and 25th days of the treatment. Peripheral blood samples from 10 healthy volunteers were also obtained for ex vivo irradiation, divided into five and irradiated at a rate of 373 kGy/h to 0, 0.1, 0.5, 1, and 3Gy γ-rays using a constant gamma source. GRP78, ATG5, LC3, ATF4, XBP1, and GADD153 genes were analyzed by quantitative real-time polymerase chain reaction (QRT-PCR) using beta 2 microglobulin (B2M) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) as references. In both groups, expressions of the selected genes have increased. It can be concluded that IR induces ER stress and related authophagy pathway in the peripheral lymphocyte cells proportionally by dose.
authors.affiliation: Department of Biology, Faculty of Science, Hacettepe University, Beytepe, Ankara, Turkey. esaglar@hacettepe.edu.tr.
authors.forename: Emel
authors.initials: E
authors.lastname: Saglar
authors.forename: Sibel
authors.initials: S
authors.lastname: Unlu
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Babalioglu
authors.forename: Saban Cakir
authors.initials: SC
authors.lastname: Gokce
authors.forename: Hatice
authors.initials: H
authors.lastname: Mergen
mesh_terms: D051701:Activating Transcription Factor 4 / Q000378:metabolism; D000328:Adult; D001343:Autophagy / Q000528:radiation effects*; D000071187:Autophagy-Related Protein 5; D004268:DNA-Binding Proteins / Q000378:metabolism; D000091342:Endoplasmic Reticulum Chaperone BiP; D059865:Endoplasmic Reticulum Stress / Q000528:radiation effects*; D005260:Female; D005720:Gamma Rays; D006360:Heat-Shock Proteins; D006801:Humans; D008297:Male; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D009369:Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000532:radiotherapy*; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism; D000071701:Regulatory Factor X Transcription Factors; D051742:Transcription Factor CHOP / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D000071717:X-Box Binding Protein 1
chemical_list: C497109:ATF4 protein, human; C502778:ATG5 protein, human; D000071187:Autophagy-Related Protein 5; C497249:DDIT3 protein, human; D004268:DNA-Binding Proteins; D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D006360:Heat-Shock Proteins; C477012:MAP1LC3A protein, human; D008869:Microtubule-Associated Proteins; D043562:Receptors, G-Protein-Coupled; D000071701:Regulatory Factor X Transcription Factors; D014157:Transcription Factors; D000071717:X-Box Binding Protein 1; C000605543:XBP1 protein, human; D051701:Activating Transcription Factor 4; D051742:Transcription Factor CHOP
keywords: Autophagy; ER Stress; Ionizing Radiation; Q-RT PCR