title: [Anti-microRNA-221 enhances radiosensitivity of colorectal carcinoma cells by up-regulating PTEN].
abstract: OBJECTIVE
  To investigate the effect of knocking-down microRNA-221 (miR-221) expression on the radiosensitivity of human colorectal carcinoma cells.
  
  
  METHODS
  Human colorectal carcinoma-derived cell line Caco2 was transfected with miR-221 antisense oligonucleotides (anti-miR-221) via Lipofectamine 2000. Real-time quantitative PCR was performed to detect the expression of miR-221 and PTEN mRNA in Caco2 cells. The changes in the protein expression of PTEN in the transfected cells were detected by Western blotting. The cell death after transfection and irradiation was detected by flow cytometry.
  
  
  RESULTS
  Transfection with anti-miR-221 caused a significant reduction in miR-221 expression (P<0.05) and up-regulated PTEN protein expression (P<0.05) in Caco2 cells. The percentage of cell death was significantly increased in anti-miR-221 group and anti-miR-221 with irradiation group (P<0.01). Anti-miR-221 significantly enhanced the radiosensitivity of Caco2 cells, which was partially reversed by PTEN-siRNA.
  
  
  CONCLUSIONS
  Anti-miR-221 can enhance the radiosensitivity of colorectal carcinoma cells by up-regulating the expression of PTEN.
authors.affiliation: Department of General Surgery, Southern Medical University, Guangzhou, China. Bennfy@163.com
authors.forename: Xiaobin
authors.initials: X
authors.lastname: Zhang
authors.forename: Kai
authors.initials: K
authors.lastname: Sun
authors.forename: Shangtong
authors.initials: S
authors.lastname: Lei
authors.forename: Yubo
authors.initials: Y
authors.lastname: Zhong
authors.forename: Haijun
authors.initials: H
authors.lastname: Deng
authors.forename: Wentao
authors.initials: W
authors.lastname: Ou
authors.forename: Chengtang
authors.initials: C
authors.lastname: Wu
mesh_terms: D018938:Caco-2 Cells / Q000528:radiation effects; D015179:Colorectal Neoplasms / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D051059:PTEN Phosphohydrolase / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D011836:Radiation Tolerance; D014162:Transfection; D015854:Up-Regulation
chemical_list: D035683:MicroRNAs; D051059:PTEN Phosphohydrolase; D012333:RNA, Messenger; C525709:MIR221, human