title: Differential roles of miR-199a-5p in radiation-induced autophagy in breast cancer cells.
abstract: Autophagy is a self-degrading process that is triggered by diverse stimuli including ionizing radiation. In this study we show novel phenomena in which transfection of miR-199a-5p mimic significantly suppresses IR-induced autophagy in MCF7 cells, and up-regulates basal and IR-induced autophagy in MDA-MB-231 breast cancer cells. We also identify DRAM1 and Beclin1 as novel target genes for miR-199a-5p. Overexpression of miR-199a-5p inhibits DRAM1 and Beclin1 expression in MCF7 cells, while it enhances expression of these genes in MDA-MB-231 cells. Furthermore, we show that miR-199a-5p sensitizes MDA-MB-231 cells to irradiation. Therefore, our data identify miR-199a-5p as a novel and unique regulator of autophagy, which plays an important role in cancer biology and cancer therapy.
authors: Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, Changchun 130021, China.
authors: Heqing
authors: H
authors: Yi
authors: Bing
authors: B
authors: Liang
authors: Jie
authors: J
authors: Jia
authors: Nan
authors: N
authors: Liang
authors: Huiying
authors: H
authors: Xu
authors: Guizhi
authors: G
authors: Ju
authors: Shumei
authors: S
authors: Ma
authors: Xiaodong
authors: X
authors: Liu
mesh_terms: D020413:3' Untranslated Regions; D051017:Apoptosis Regulatory Proteins / Q000235:genetics* / Q000378:metabolism; D001343:Autophagy / Q000528:radiation effects*; D001483:Base Sequence; D000071186:Beclin-1; D001665:Binding Sites; D001943:Breast Neoplasms; D059447:Cell Cycle Checkpoints / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects; D005260:Female; D015870:Gene Expression; D015972:Gene Expression Regulation, Neoplastic; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D049410:Luciferases, Renilla / Q000096:biosynthesis / Q000235:genetics; D061986:MCF-7 Cells; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D021381:Protein Transport; D034622:RNA Interference; D011836:Radiation Tolerance; D011993:Recombinant Fusion Proteins / Q000378:metabolism
chemical_list: D020413:3' Untranslated Regions; D051017:Apoptosis Regulatory Proteins; C491997:BECN1 protein, human; D000071186:Beclin-1; C512709:DRAM1 protein, human; C477012:MAP1LC3A protein, human; D008565:Membrane Proteins; D035683:MicroRNAs; D008869:Microtubule-Associated Proteins; D011993:Recombinant Fusion Proteins; C531408:mirn199 microRNA, human; D049452:Green Fluorescent Proteins; D049410:Luciferases, Renilla