摘要
目的:观察不同放疗剂量对食管癌细胞EC9706耐药基因MDR1表达水平的影响,同时分析其对细胞化疗耐药性的作用。方法:对食管癌细胞分别按常规剂量组(2 Gy/d.f)和小剂量组(1 Gy/d.f)进行分次外照射,共20次。采用实时定量PCR(QRT-PCR)和Western blot对外照射前后处于缺氧培养下的食管癌细胞MDR1表达水平进行检测。MTT实验评估化疗细胞抑制率。结果:照射前缺氧培养下的食管癌细胞MDR1表达水平即较对照组明显升高(P<0.05)。接受20次2 Gy/d.f照射后食管癌细胞的MDR1表达水平明显高于单纯缺氧培养组(P<0.05),但小剂量照射组的MDR1表达则明显减低(P<0.05),同时其耐药指数亦明显下降(P<0.05)。结论:同缺氧条件下进行常规剂量分次外照射相比,小剂量分次外照射可以缓解食管癌细胞的耐药程度,推测其辅助化疗疗效应较好。
AIM：To investigate the dose effect of fractioned ionizing radiation on the expression of MDR1 in human esophageal cancer cells.METHODS：The mRNA and protein levels of MDR1 in esophageal caner cell line EC9706 incubated in culture containing 150 μmol/L CoCl2 pre-and post-irradiation were measured by quantitative reverse transcription-polymerase chain reaction（QRT-PCR） and Western blot analysis,respectively.The chemo-sensitivity was analyzed by MTT.RESULTS：Comparing with the control group,hypoxia culture significantly induced MDR1 expression（P〈0.05）.After 20 fractions of irradiation,the MDR1 expression was significantly up-regulated in 2 Gy/d·f group（P〈0.05）,while obviously decreased in 1 Gy/d·f group（P〈0.05）.Consequently,the cell inhibitory rate was significantly reduced in 2 Gy/d·f group,but increased in 1 Gy/d·f group（P〈0.05）.CONCLUSION：These results indicate that MDR1 is differentially modulated by different doses of fractionated radiation,which should be taken into account when combining radiotherapy chemotherapy for esophageal cancer patients.
出处
《细胞与分子免疫学杂志》
CAS
CSCD
北大核心
2010年第2期152-153,156,共3页
Chinese Journal of Cellular and Molecular Immunology
基金
陕西省卫生厅基金资助项目(08E06)
关键词
多药耐药基因
食管癌
放疗
化疗
MDRI
esophageal cancer
radiotherapy
chemotherapy
