Xie Y, Liu J B, Li J M, Zhang C, Lu C X, Wen Z J
Deparment of Gastrointestinal Surgery, Henan People's Hospital, Zhengzhou 450000, China.
Department of Oncology, Henan People's Hospital, Zhengzhou 450000, China.
Zhonghua Zhong Liu Za Zhi. 2021 Apr 23;43(4):449-456. doi: 10.3760/cma.j.cn112152-20200116-00040.
To investigate the expression of circular ribonucleic acid ABCB10 (circABCB10) in colorectal cancer tissues and cells and its effects on cell biological behavior, radiosensitivity and growth of subcutaneous xenografts. The tumor tissue and adjacent tissue from colorectal cancer patients treated in Henan People's Hospital were collected from January 2018 to December 2018. Quantitative polymerase chain reaction (qPCR) was used to detect the expressions of circABCB10 and miR-217, cell viability was detected by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT), cell apoptosis rate was detected by flow cytometry, cell migration and invasion were detected by Transwell method, cell radiosensitivity was detected by colony formation assay. The downstream miRNAs of circABCB10 were predicted by Circular RNA Interactome and verified by the dual luciferase reporter gene experiment. The effect of circABCB10 on the growth of transplanted tumor was examined in nude mice. The expression level of circABCB10 mRNA in colorectal cancer tissues was (3.97±2.12), higher than (1.13±0.64) in adjacent tissues (<0.05). The expression level of circABCB10 mRNA in FHC cells was (1.00±0.09), lower than that (4.53±0.44) in SW480, (3.12±0.32) in HCT116 and (3.51±0.36) in HT29 cells, respectively (all <0.05). The MTT results showed that the absorbance values of SW480 cells in si-circABCB10-1 group at 48 and 72 hours after transfection were (0.36±0.04) and (0.43±0.04), lower than (0.48±0.05) and (0.82±0.08) in circ-negative control (NC) group, respectively (all <0.05). The number of migrating cells and invasive cells in si-circABCB10-1 group were (45±8) and (34±7), lower than (106±21) and (84±15) in circ-NC group, respectively (all <0.01). The radiosensitization ratio was 1.632. The results of subcutaneous transplantation assay showed that the tumor volume and tumor weight of the si-circABCB10-1 group were significantly lower than circ-NC group after 8 days of inoculation ( all <0.05). MiR-217 is a target gene of circABCB10. Inhibition of miR-217 reversed the inhibitory effect of circABCB10 silencing on cell proliferation, migration, invasion and subcutaneous xenograft growth in nude mice and the radiosensitization activity. Silence of circABCB10 can up-regulate the expression of miR-217 to inhibit the proliferation, migration, invasion and growth of subcutaneous xenografts and increase the radiosensitivity of SW480 cells, which reveals the underlying molecular mechanism of colorectal cancer progression and provides a new sensitizing target for clinical radiotherapy of colorectal cancer.
探讨环状核糖核酸ABCB10（circABCB10）在结直肠癌组织和细胞中的表达及其对细胞生物学行为、放射敏感性和皮下异种移植瘤生长的影响。收集2018年1月至2018年12月在河南省人民医院接受治疗的结直肠癌患者的肿瘤组织及癌旁组织。采用定量聚合酶链反应（qPCR）检测circABCB10和miR-217的表达，用3-(4,5-二甲基-2-噻唑基)-2,5-二苯基-2H溴化四氮唑（MTT）法检测细胞活力，流式细胞术检测细胞凋亡率，Transwell法检测细胞迁移和侵袭能力，克隆形成实验检测细胞放射敏感性。通过Circular RNA Interactome预测circABCB10的下游miRNAs，并经双荧光素酶报告基因实验验证。在裸鼠中检测circABCB10对移植瘤生长的影响。结直肠癌组织中circABCB10 mRNA表达水平为（3.97±2.12），高于癌旁组织的（1.13±0.64）（<0.05）。FHC细胞中circABCB10 mRNA表达水平为（1.00±0.09），分别低于SW480细胞的（4.53±0.44）、HCT116细胞的（3.12±0.32）和HT29细胞的（3.51±0.36）（均<0.05）。MTT结果显示，转染si-circABCB10-1组SW480细胞在转染后48小时和72小时的吸光度值分别为（0.36±0.04）和（0.43±0.04），低于circ阴性对照（NC）组的（0.48±0.05）和（0.82±0.08）（均<0.05）。si-circABCB10-1组迁移细胞数和侵袭细胞数分别为（45±8）和（34±7），低于circ-NC组的（106±21）和（84±15）（均<0.01）。放射增敏比为1.632。皮下移植实验结果显示，接种8天后，si-circABCB10-1组的肿瘤体积和肿瘤重量均显著低于circ-NC组（均<0.05）。miR-217是circABCB10的靶基因。抑制miR-217可逆转circABCB10沉默对细胞增殖、迁移、侵袭以及裸鼠皮下异种移植瘤生长的抑制作用和放射增敏活性。沉默circABCB10可上调miR-217表达，抑制SW480细胞增殖、迁移、侵袭及皮下异种移植瘤生长，并增加其放射敏感性。这揭示了结直肠癌进展的潜在分子机制，为结直肠癌临床放疗提供了新的增敏靶点。
