circ_0000267靶向miR-198对急性淋巴细胞白血病细胞KOCL44增殖和凋亡的影响

目的探讨circ_0000267对急性淋巴细胞白血病（ALL）KOCL44细胞增殖和凋亡的影响及其作用机制。 方法选择ALL细胞株KOCL44为研究对象，分别将小干扰RNA （siRNA）阴性对照（si-NC）、circ_0000267 siRNA （si-circ_0000267）、微小RNA （miRNA）阴性对照（miR-NC）、miR-198模拟物（miR-198）、circ_0000267 siRNA+miRNA抑制剂阴性对照（si-circ_0000267+anti-miR-NC）和circ_0000267 siRNA+miR-198抑制剂（si-circ_0000267+anti-miR-198）转染细胞，48 h后通过RT-qPCR检测细胞circ_0000267和miR-198相对表达水平，采用CCK-8法检测KOCL44细胞的增殖水平，流式细胞术实验检测KOCL44细胞的凋亡水平，Western blot检测KOCL44细胞Ki-67、Bcl-2和Bax蛋白表达水平，通过双荧光素酶报告实验验证circ_0000267和miR-198靶向关系。两组间比较采用独立样本t检验。 结果与健康志愿者比较，ALL患者circ_0000267表达水平（1.00±0.06比3.19±0.21）上调，miR-198表达水平（1.00±0.07比0.41±0.03）下调，差异有统计学意义（P < 0.05）。敲低circ_0000267或者过表达miR-198可抑制KOCL44细胞增殖（0.68±0.05比0.32±0.02、0.69±0.06比0.39±0.03）、Ki-67 （0.84±0.06比0.37±0.03、0.85±0.06比0.45±0.04）和Bcl-2蛋白表达（0.63±0.05比0.22±0.02、0.65±0.04比0.29±0.02），促进细胞凋亡（6.53±0.51）﹪比（24.29±2.06）﹪、（7.38±0.57）﹪比（20.03±1.66）﹪]和Bax蛋白表达（0.31±0.03比0.77±0.04、0.30±0.02比0.71±0.04），差异有统计学意义（P < 0.05）。双荧光素酶报告实验验证circ_0000267可以靶向miR-198表达，干扰miR-198表达可以逆转抑制circ_0000267表达对KOCL44细胞的增殖和凋亡的作用，差异有统计学意义（P < 0.05）。 结论circ_0000267通过调控miR-198抑制ALL细胞增殖，并促进凋亡，为临床治疗ALL提供新的依据。

Role of circ_0000267 targeting miR-198 in the proliferation and apoptosis of acute lymphoblastic leukemia cells KOCL44

Objective To study the role of circ_0000267 in the proliferation and apoptosis of acute lymphoblastic leukemia(ALL)and its mechanism.Methods siRNA Negative control(si-NC),circ_0000267 siRNA(si-circ_0000267),miRNA negative control(miR-NC),miR-198 mimics(miR-198),si-circ_0000267+anti-miR-NC and si-circ_0000267+anti-miR-198 were transfected into the acute lymphocytic leukemia cell line KOCL44.The cells were collected 48 h after transfection.The expressions of circ_0000267 and miR-198 were detected by RT-qPCR;CCK-8 method was used to detect the proliferation of KOCL44 cells;flow cytometry was used to detect the apoptosis of KOCL44 cells;Western blot was used to detect the protein expressions of Ki-67,Bcl-2 and Bax;and double luciferase reporting assay was used to verify the relationship between circ_0000267 and miR-198.The comparison between the two groups was analyzed by independent sample t test.Results Compared with healthy volunteers,the expression of circ_000026(1.00±0.06 vs 3.19±0.21)was up-regulated in ALL patients,and the expression of miR-198(1.00±0.07 vs 0.41±0.03)was down-regulated,and the difference was statistically significant(P<0.05).Knockdown of circ_0000267 or overexpression of miR-198 can significantly inhibit the proliferation of KOCL44 cells(0.68±0.05 vs 0.32±0.02,0.69±0.06 vs 0.39±0.03),the protein expression of Ki-67(0.84±0.06 vs 0.37±0.03,0.85±0.06 vs 0.45±0.04)and Bcl-2(0.63±0.05 vs 0.22±0.02,0.65±0.04 vs 0.29±0.02),and increase the rate of apoptosis(6.53±0.51]﹪vs24.29±2.06]﹪,7.38±0.57]﹪vs20.03±1.66]﹪)and the protein expression of Bax(0.31±0.03 vs 0.77±0.04,0.30±0.02 vs 0.71±0.04).All the differences were statistically significant(P<0.05).The dual luciferase report experiment verified that circ_0000267 can target miR-198,and interference with the expression of miR-198 reversed the effect of inhibiting the expression of circ_0000267 on the proliferation and apoptosis of KOCL44 cells,and the difference was also statistically significant(P<0.05).Conclusions circ_0000267 inhibits all cell proliferation and promotes apoptosis by regulating miR-198,providing a new basis for clinical treatment of all.