title: [Radiosensitization Induced by ANTP-SmacN7 Fusion Peptide in H460 Cell Line].
abstract: BACKGROUND
  The curative effect of radiotherapy may be limited by the radioresistance of tumor. Mimetic compounds of Second mitochondria-derived activator of caspase (Smac) were hopeful to become new drugs of radiosensitization for tumor because they can increase radiation induced apoptosis in tumor cells. The aim of present study is to observe the radiosensitization effect of a new Smac mimetic ANTP-SmacN7 fusion peptide in H460 cell line.
  
  
  METHODS
  In order to observe if the fusion peptide can enter into tumor cell, ANTP-SmacN7 fusion peptide was synthesized and linked by FITC. H460 cell was divided into control, radiation only, ANTP-SmacN7 only and ANTP-SmacN7 combined with radiation group. The cells were exposed by 0, 2, 4 and 6 Gy and the concentration of ANTP-SmacN7 was 20 μmol/L. Proliferation of H460 tumor cell was detected by WST-1 assay. There are four groups in the present study: control group, radiation group, ANTP-SmacN7 group and ANTP-SmacN7 combined with radiation group. Apoptosis was detected by flow cytometry at 24 and 48 hours after the treatment of all the groups. The level of caspase3 and cleaved caspase3 were detected by Western blot assay.
  
  
  RESULTS
  ANTP-SmacN7 can enter into cells and promote the radiosensitization of H460 cell obviously (F=25.1, P<0.01, sensitivity enhancement ratio was 1.86). The treatment of ANTP-SmacN7 combined with radiation decreased the cloning forming efficiency (χ2=45.2, P<0.01; χ2=40.3, P<0.01), activated caspase3 by promoting the expression of cleaved caspase3 and increased the apoptosis of H460 cell line.
  
  
  CONCLUSIONS
  ANTP-SmacN7 fusion peptide had remarkably radiosensitization effect on H460 cell line. ANTP-SmacN7 fusion peptide might be hopeful to be applied in radiosensitization therapy as a new Smac mimetic polypeptide in the future.
authors.affiliation: Institute of Radiation Medicine of Chinese Academy of Medical Science and Peking Union Medical College, Tianjin Key Lab of Radiation and Molecular Nuclear Medicine, Tianjin 300192, China.
authors.forename: Baona
authors.initials: B
authors.lastname: Liu
authors.affiliation: Institute of Radiation Medicine of Chinese Academy of Medical Science and Peking Union Medical College, Tianjin Key Lab of Radiation and Molecular Nuclear Medicine, Tianjin 300192, China.
authors.forename: Liqing
authors.initials: L
authors.lastname: Du
authors.affiliation: Institute of Radiation Medicine of Chinese Academy of Medical Science and Peking Union Medical College, Tianjin Key Lab of Radiation and Molecular Nuclear Medicine, Tianjin 300192, China.
authors.forename: Chang
authors.initials: C
authors.lastname: Xu
authors.affiliation: Institute of Radiation Medicine of Chinese Academy of Medical Science and Peking Union Medical College, Tianjin Key Lab of Radiation and Molecular Nuclear Medicine, Tianjin 300192, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Institute of Radiation Medicine of Chinese Academy of Medical Science and Peking Union Medical College, Tianjin Key Lab of Radiation and Molecular Nuclear Medicine, Tianjin 300192, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Tianjin Academy of Traditional Chinese Medicine Affiliated Hospital, Tianjin 300120, China.
authors.forename: Zhiyi
authors.initials: Z
authors.lastname: Song
authors.affiliation: Institute of Radiation Medicine of Chinese Academy of Medical Science and Peking Union Medical College, Tianjin Key Lab of Radiation and Molecular Nuclear Medicine, Tianjin 300192, China.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Sun
authors.affiliation: Institute of Radiation Medicine of Chinese Academy of Medical Science and Peking Union Medical College, Tianjin Key Lab of Radiation and Molecular Nuclear Medicine, Tianjin 300192, China.
authors.forename: Jinhan
authors.initials: J
authors.lastname: Wang
authors.affiliation: Institute of Radiation Medicine of Chinese Academy of Medical Science and Peking Union Medical College, Tianjin Key Lab of Radiation and Molecular Nuclear Medicine, Tianjin 300192, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
mesh_terms: D017209:Apoptosis / Q000528:radiation effects; D051017:Apoptosis Regulatory Proteins; D045744:Cell Line, Tumor; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000008:administration & dosage* / Q000378:metabolism; D008175:Lung Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000503:physiopathology / Q000532:radiotherapy*; D024101:Mitochondrial Proteins / Q000008:administration & dosage* / Q000378:metabolism; D010455:Peptides / Q000008:administration & dosage* / Q000378:metabolism; D011838:Radiation-Sensitizing Agents / Q000008:administration & dosage* / Q000378:metabolism
chemical_list: D051017:Apoptosis Regulatory Proteins; C412403:DIABLO protein, human; D047908:Intracellular Signaling Peptides and Proteins; D024101:Mitochondrial Proteins; D010455:Peptides; D011838:Radiation-Sensitizing Agents