环状RNA-7靶向微小RNA-7促进食管鳞癌细胞放疗抵抗的实验研究

目的:探讨环状RNA-7(circularRNA, ciRS)-7在食管鳞癌细胞放疗抵抗中的作用及生物学机制。方法:采用慢病毒转染食管鳞癌细胞系KYSE410和KYSE510构建ciRS-7敲降细胞系(分为正常对照组和sh#1组、sh#2组)。不同剂量射线(2 Gy组、4 Gy组、8 Gy组)照射上述细胞，收集各组细胞...

Experimental study of circularRNA-7 promoting the radiotherapy resistance of esophageal squamous cell carcinoma by targeting microRNA-7

Objective To explore the effects and mechanism of ciRS-7 on the radiotherapy resistance of esophageal squamous cell carcinoma(ESCC).Methods The ciRS-7 knockdown cell line(normal control group and sh#1 group,sh#2 group)was constructed with KYSE410 and KYSE510 ESCC cell lines using a lentivirus transfection.The above cells were irradiated with different doses of rays(2,4,and 8 GY),and stained.The ratio of viable cells was measured by the flow cytometry.The relationship between ciRS-7 and miR-7 was validated by the dual-luciferase reporterassay system.KYSE410 cells were divided into normal group and ciRS-7 knockdown group.The miR-7 expression was detected by RT-qPCR.The KYSE410 cells were transfected with shRNA,and divided into interference groups(normal control group,ciRS-7 knockdown group),overexpression groups(ciRS-7 and miR-7 co-overexpression group,negative control group,miR-7 overexpression group).The protein expression of B cell lymphoma/leukemia-2 protein(bcl-2)in each group was detected by Western blotting.The independent sample t test was used for the comparison between two groups.The difference was statistically significant with P<0.05.Results The expression of ciRS-7 in sh#1 group(0.36±0.03)and sh#2 group(0.37±0.12)in KYSE410 cells was lower than that in normal control group(1.00±0.01,t=24.460,8.910,P<0.05).The expression of ciRS-7 in sh#1 group(0.40±0.08)and sh#2 group(0.34±0.08)in KYSE510 cells was lower than that in normal control group(1.00±0.08,t=8.514,9.550,P<0.05).After radiation of 4 Gy,the percentages of viable cells in sh#1 group(37.00±3.07)%]and sh#2 group(39.50±0.70)%]in KYSE410 cells were lower than those in normal control group(63.50±6.36)%,t=7.400,5.301,P<0.05],and those in sh#1 group(39.00±8.48)%]and sh#2 group(39.50±0.70)%]of KYSE510 cells were lower than those in normal control group(73.50±6.36)%,t=4.600,7.509,P<0.05].After radiation of 8 Gy,the percentages of viable cells in sh#1 group(22.50±3.53)%]and sh#2 group(39.50±0.70)%]of KYSE410 were lower than those in normal control group(50.50±2.12)%,t=9.604,11.800,P<0.05)],and those in sh#1 group(33.00±2.82)%]and sh#2 group(31.00±2.82)%]of KYSE510 cells were lower than those in normal control group(60.50±2.12)%,t=11.000,11.800,P<0.05].The expression of miR-7 in the ciRS-7 overexpression group(1.00±0.23)in KYSE410 cells was lower than that in normal control group(0.54±0.08,t=3.191,P<0.05).The dual-luciferase reporter assay system confirmed that ciRS-7 absorbed miR-7.The bcl-2 expression in miR-7 and ciRS-7 co-overexpression group was higher than that in miR-7 overexpression group(0.59±0.11,t=6.013,P<0.05)and ciRS-7 knockdown group(0.83±0.08,t=3.717,P<0.05).Conclusion ciRS-7 promotes radiotherapy resistance of ESCC by targeting miR-7.