title: The effects of X-ray irradiation on the proliferation and apoptosis of MCF-7 breast cancer cells.
abstract: To investigate the effects of X-ray irradiation on the proliferation and apoptosis of MCF-7 breast cancer cells; MCF-7 breast cancer cells were irradiated with X-ray. After irradiation, morphological changes and growth inhibition rate of the irradiated cells were observed under an inverted microscope. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to assess the proliferation of the irradiated MCF-7 cells. Transmission electron microscope was used to observe the morphology and ultrastructure of the irradiated MCF-7 cells. Western blotting was used to analyze the expression level of apoptosis-related protein caspase-3. Our results showed, at 48 h after the irradiation (0 Gy and 8 Gy), cells oval in shape, cell shrinkage or swelling and partial formation of debris under inverted microscope; as well as cytoplasmic vacuolization or inspissation, increased electron density of cytoplasm, structural damage of organelles, blurred mitochondrial cristae and chromatin margination under transmission electron microscopy; the survival rate of MCF-7 cells in X-ray group was 17.3% lower than that in control group (0 Gy) (p < 0.001); while caspase-3 expression increased evidently in X-ray group compared with control group (0 Gy) (p < 0.05). In conclusion, X-ray irradiation can inhibit the proliferation of MCF-7 cells and induce apoptosis through increasing caspase-3 expression.
authors.affiliation: Department of Oncology, Hubei Key Laboratory of Tumor Biological Behaviors, Hubei Cancer Clinical Study Center, Zhongnan Hospital, Wuhan University , Wuhan , China .
authors.forename: Dou-Lin
authors.initials: DL
authors.lastname: Li
authors.forename: Lei
authors.initials: L
authors.lastname: Wei
authors.forename: Xian-Mei
authors.initials: XM
authors.lastname: Wen
authors.forename: Hui
authors.initials: H
authors.lastname: Song
authors.forename: Qun
authors.initials: Q
authors.lastname: Li
authors.forename: Jia-Wei
authors.initials: JW
authors.lastname: Lv
authors.forename: Chang-Chun
authors.initials: CC
authors.lastname: Kuang
authors.forename: Zheng-Zhuan
authors.initials: ZZ
authors.lastname: Wei
authors.forename: Jing-Wei
authors.initials: JW
authors.lastname: Zhang
mesh_terms: D017209:Apoptosis / Q000528:radiation effects*; D001943:Breast Neoplasms / Q000378:metabolism / Q000648:ultrastructure*; D053148:Caspase 3 / Q000378:metabolism; D049109:Cell Proliferation / Q000528:radiation effects*; D048430:Cell Shape / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects; D005260:Female; D006801:Humans; D061986:MCF-7 Cells; D046529:Microscopy, Electron, Transmission; D013997:Time Factors; D014965:X-Rays
chemical_list: C505407:CASP3 protein, human; D053148:Caspase 3