X线辐射剂量对结直肠癌细胞中microRNA-221和p57^(kip2)表达的影响  

Effects of X-ray Dose on Expression of microRNA-221 and p57^(kip2) in Human Colorectal Carcinoma Cells

作　　者：孙凯[1] 张晓槟[1] 邓海军[1] 钟育波[2] 雷尚通[1] 区文弢[1] 吴承堂[1] 

机构地区：[1]南方医科大学南方医院普通外科,广州510515 [2]南方医科大学附属佛山医院普外三科

出　　处：《肿瘤防治研究》2013年第10期921-924,共4页Cancer Research on Prevention and Treatment

基　　金：国家自然科学基金青年科学基金资助项目(81101896);广东省科技计划项目资助课题(2012B031800141);广东省医学科研基金资助项目(B2012221);广东高校优秀青年创新人才培养计划资助项目(2012LYM0035);佛山市卫生局医学科研基金资助项目(2012079);南方医科大学南方医院院长基金资助项目(2011B008)

摘　　要：目的探讨不同剂量X线辐射对人结直肠癌Caco2细胞系中microRNA-221(miR-221)和p57kip2表达的影响。方法常规培养Caco2细胞系并分为5组,分别给予不同剂量X线(0、2、4、6和8 Gy)照射,24 h后提取细胞总RNA和蛋白质,应用real-time Q-PCR检测细胞中miR-221和p57kip2mRNA的表达水平,Western blot检测p57kip2蛋白的表达变化。结果 Caco2细胞系在不同照射剂量下,miR-221表达水平随着照射剂量的增加而增加,而p57kip2蛋白表达水平则随着照射剂量的增加而逐步降低,且呈剂量依赖效应,两者差异均具有统计学意义(P<0.05)。结论放射线辐射剂量可影响结直肠癌细胞中miR-221/p57kip2调控通路,抑制miR-221表达可能会提高结直肠癌细胞的放射敏感度。Objective To investigate the effects of X-ray dose on the expression of microRNA-221（miR-221） and p57^kip2 in human colorectal carcinoma （CRC） cells. Methods Conventionally cultured Caco2 cells were divided into 5 groups with different doses of X-ray （0, 2, 4,6 and 8 Gy） respectively. The total RNA and protein of the cells were extracted after irradiation for 24 h,The expression level of miR-221 and p57^kip2 mRNA were detected by real-time Q-PCR. The expression of p57^kip2 in cells was detected by Western blot analysis. Results The radiation dose of X-ray had significant effect on the expression of miR-221 and p57^kip2 protein in human Caco2 cells in a dose-dependent manner. The miR-221 expression level improved gradually with the increase of irradiation dose while the p57^kip2 protein expression level reduced gradually （P〈0.05）. Conclusion Radiation dose could affect the miR-221/p57^kip2 regulation pathways in CRC cells. Suppressed miR-221 expression may enhance the radiosensitivity of CRC cells.

关 键 词：结直肠癌 microRNA-221 P57^KIP2 辐射剂量 放射敏感度 

分 类 号：R735.3[医药卫生—肿瘤]