Autophagy inhibition by chloroquine sensitizes HT-29 colorectal cancer cells to concurrent chemoradiation

查看全文 作　　者：Caitlin A [1]Schonewolf;Monal [1]Mehta;Devora [1]Schiff;Hao [1]Wu;Bruce G [1]Haffty;Vassiliki [2]Karantza;Salma K [1]Jabbour

机构地区：[1]Departments of Radiation Oncology,Robert Wood Johnson Medical School,University of Medicine and Dentistry of New Jersey,The Cancer Institute of New Jersey,New Brunswick,NJ 08903,United States;[2]Departments of Medicine,Robert Wood Johnson Medical School,University of Medicine and Dentistry of New Jersey,The Cancer Institute of New Jersey,New Brunswick,NJ 08903,United States

出　　处：《World Journal of Gastrointestinal Oncology》索引2014年第6卷第3期,共9页

摘　　要：AIM:To investigate whether the inhibition of autophagy by chloroquine(CQ)sensitizes rectal tumors to radiation therapy(RT)or concurrent chemoradiation(chemoRT).METHODS:In vitro,HCT-116 and HT-29 colorectal cancer(CRC)cell lines were treated as following:(1)PBS;(2)CQ;(3)5-fluorouracil(5-FU);(4)RT;(5)CQ and RT;(6)5-FU and RT;(7)CQ and 5-FU;and(8)5-FU and CQ and RT.Each group was then exposed to various doses of radiation(0-8 Gy)depending on the experiment.Cell viability and proliferative capacity were measured by3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)and clonogenic assays.Clonogenic survivalcurves were constructed and compared across treatment groups.Autophagy status was determined by assessing the LC3-Ⅱto LC3-Ⅰratio on western blot analysis,autophagosome formation on electron microscopy and identification of a perinuclear punctate pattern with GFPlabeled LC3 on fluorescence microscopy.Cell cycle arrest and cell death were evaluated by FACS and AnnexinⅤanalysis.All experiments were performed in triplicate and statistical analysis was performed by the student’s t test to compare means between treatment groups.RESULTS:RT(2-8 Gy)induced autophagy in HCT-116and HT-29 CRC cell lines at 4 and 6 h post-radiation,respectively,as measured by increasing LC3-Ⅱto LC3-Ⅰratio on western blot.Additionally,electron microscopy demonstrated autophagy induction in HT-29 cells24 h following irradiation at a dose of 8 Gy.Drug treatment with 5-FU(25μmol/L)induced autophagy and the combination of 5-FU and RT demonstrated synergism in autophagy induction.CQ(10μmol/L)alone and in combination with RT effectively inhibited autophagy and sensitized both HCT-116 and HT-29 cells to treatment with radiation(8 Gy;P<0.001 and 0.00001,respectively).Significant decrease in clonogenic survival was seen only in the HT-29 cell line,when CQ was combined with RT at doses of 2 and 8 Gy(P<0.5 and P=0.05,respectively).There were no differences in cell cycle progression or Annexin V staining upon CQ addition to RT.CONCLUSION:Autophagy inhibition by CQ increases CRC cell sensitivity to concurrent treatment with 5-FU and RT in vitro,suggesting that addition of CQ to chemoRT improves CRC treatment response. 关键词：AUTOPHAGY CHLOROQUINE RADIOSENSITIZATION COLORECTAL cancer

相关文献

参考文献（7）
引证文献（14）
耦合文献（7）

参考文献(7)

引证文献(14)

耦合文献(7)

互联网出版许可证新出网证(渝)字10号全国400电话 - 免长途话费

Autophagy inhibition by chloroquine sensitizes HT-29 colorectal cancer cells to concurrent chemoradiation

参考文献(7)

引证文献(14)

耦合文献(7)

用户提示