title: MiR-34a in age and tissue related radio-sensitivity and serum miR-34a as a novel indicator of radiation injury.
abstract: MiR-34a, a direct target of p53, has shown to exert potent anti-proliferative effects. It has also been found that miR-34a can be induced by irradiation in vitro and in vivo. However, the relationship between miR-34a and radio-sensitivity, and its potential diagnostic significance in radiation biology, remain unclear. This study found that differing responses to ionizing radiation (IR) of young and adult mice were related to miR-34a. First, we found that miR-34a could be induced in many organs by radiation of both young and adult mice. However, the level of miR-34a induced by young mice was much higher when compared to adult mice. Next, we found that miR-34a played a critical role in radio-sensitivity variations of different tissues by enhancing cell apoptosis and decreasing cell viability. We also found that the induction of miR-34a by radiation was in a p53 dependent manner and that one possible downstream target of miR-34a that lead to different radio-sensitivity was the anti-apoptosis molecular Bcl-2. However, over-expression of miR-34a and knockdown of Bcl-2 could significantly enhance the radio-sensitivity of different cells while inhibition of miR-34a could protect cells from radiation injury. Finally, we concluded that miR-34a could be stable in serum after IR and serve as a novel indicator of radiation injury. Taken together, this data strongly suggests that miR-34a may be a novel indicator, mediator and target of radiation injury, radio-sensitivity and radioprotection.
authors: Department of Radiation Medicine, Faculty of Naval Medicine, Second Military Medical University, Shanghai, PR China.
authors: Cong
authors: C
authors: Liu
authors: Chuanfeng
authors: C
authors: Zhou
authors: Fu
authors: F
authors: Gao
authors: Shengyun
authors: S
authors: Cai
authors: Chao
authors: C
authors: Zhang
authors: Luqian
authors: L
authors: Zhao
authors: Fang
authors: F
authors: Zhao
authors: Fei
authors: F
authors: Cao
authors: Jing
authors: J
authors: Lin
authors: Yanyong
authors: Y
authors: Yang
authors: Jin
authors: J
authors: Ni
authors: Jun
authors: J
authors: Jia
authors: Wei
authors: W
authors: Wu
authors: Li
authors: L
authors: Zhou
authors: Jianguo
authors: J
authors: Cui
authors: Wei
authors: W
authors: Zhang
authors: Bailong
authors: B
authors: Li
authors: Jianming
authors: J
authors: Cai
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000235:genetics / Q000528:radiation effects; D002460:Cell Line; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000235:genetics / Q000528:radiation effects; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D035683:MicroRNAs / Q000235:genetics* / Q000502:physiology; D011832:Radiation Injuries / Q000235:genetics*; D011836:Radiation Tolerance / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D035683:MicroRNAs