葛根素通过miR-490/E3泛素连接酶抑制非小细胞肺癌细胞生长、侵袭和迁移

目的 研究葛根素抑制非小细胞肺癌细胞生长、侵袭和迁移的机制。方法 培养A549细胞,采用不同浓度的葛根素处理细胞。CCK-8法检测细胞增殖抑制率(IR);qRT-PCR法检测细胞中miR-490和E3泛素连接酶(DTL)mRNA的表达情况;构建miR-490过表达对照组、miR-490过表达模拟物组、miR-490沉默阴性对照组、miR-490沉默组,采用双荧光素酶报告分析miR-490和DTL的靶向关系。将20 μmol/L葛根素处理过的细胞分为对照组、葛根素组、葛根素+miR-490阴性对照组、葛根素+miR-490沉默模拟物组、葛根素+miR-490沉默模拟物+DTL阴性对照组、葛根素+miR-490沉默模拟物+DTL沉默质粒组。Transwell法检测细胞迁移和侵袭。Western blot检测上皮细胞-间充质转化进程标志因子E-钙黏蛋白(E-cadherin)、N-钙黏蛋白(N-cadherin)和波形蛋白(Vimentin)的表达。结果 随着葛根素浓度升高,细胞抑制率逐步升高,差异有统计学意义(F=105.375,P<0.001);且miR-490表达逐步升高(F=32.919,P<0.001),DTL表达逐步降低(F=116.120,P<0.001)。双荧光素酶报告分析显示,与miR-490过表达对照组相比,miR-490过表达模拟物组荧光素酶活性显著降低(t=7.762,P=0.016),miR-490 mRNA表达显著升高(t=13.319,P<0.001),DTL mRNA表达显著降低(t=7.415,P=0.002);与miR-490沉默阴性对照组相比,miR-490沉默组细胞中miR-490表达显著降低(t=9.523,P=0.001),DTL mRNA的表达显著升高(t=11.305,P<0.001)。Western blot检测结果显示,与miR-490过表达对照组相比,miR-490过表达模拟物组的DTL蛋白表达显著降低(t=7.953,P=0.001);与miR-490沉默阴性对照组相比,miR-490沉默组细胞中的DTL 蛋白表达显著升高(t=10.552,P<0.001)。经葛根素处理后,与对照组相比,葛根素组细胞miR-490表达显著升高(t=10.255,P=0.001),DTL mRNA表达显著降低(t=6.682,P=0.003);与葛根素+miR-490阴性对照组相比,葛根素+miR-490沉默模拟物组细胞中miR-490表达显著降低(t=10.995,P<0.001),DTL mRNA表达显著升高(t=12.478,P<0.001);与葛根素+miR-490沉默模拟物+DTL阴性对照组相比,葛根素+miR-490沉默模拟物+DTL沉默质粒组细胞miR-490表达差异无统计学意义(t=1.081,P=0.341),DTL mRNA表达显著降低(t=14.321,P<0.001)。与葛根素+miR-490阴性对照组相比,葛根素+miR-490沉默模拟物组DTL蛋白表达显著升高(t=11.423,P<0.001);与葛根素+miR-490沉默模拟物+DTL阴性对照组相比,葛根素+miR-490沉默模拟物+DTL沉默质粒组细胞的DTL蛋白表达显著降低(t=12.080,P<0.001)。与对照组相比,葛根素组细胞增殖能力显著降低(F=129.27,P<0.001);与葛根素+miR-490阴性对照组相比,葛根素+miR-490沉默模拟物组细胞增殖能力显著升高(F=75.12,P<0.001);与葛根素+miR-490沉默模拟物+DTL阴性对照组相比,葛根素+miR-490沉默模拟物+DTL沉默质粒组细胞增殖能力显著降低(F=52.59,P<0.001)。与对照组相比,葛根素组细胞迁移能力显著降低(t=8.963,P=0.001);与葛根素+miR-490阴性对照组相比,葛根素+miR-490沉默模拟物组细胞迁移能力显著升高(t=12.117,P<0.001);与葛根素+miR-490沉默模拟物+DTL阴性对照组相比,葛根素+miR-490沉默模拟物+DTL沉默质粒组细胞迁移能力显著降低(t=12.934,P<0.001)。与对照组相比,葛根素组细胞侵袭能力显著降低(t=4.710,P=0.009);与葛根素+miR-490阴性对照组相比,葛根素+miR-490沉默模拟物组细胞侵袭能力显著升高(t=13.264,P<0.001);与葛根素+miR-490沉默模拟物+DTL阴性对照组相比,葛根素+miR-490沉默模拟物+DTL沉默质粒组细胞侵袭能力显著降低(t=13.476,P<0.001)。与对照组相比,葛根素组E-cadherin蛋白表达显著升高(t=7.137,P=0.002),N-cadherin(t=8.828,P=0.001)和Vimentin蛋白表达(t=6.594,P=0.003)显著降低;与葛根素+miR-490阴性对照组相比,葛根素+miR-490沉默模拟物组细胞中E-cadherin蛋白表达显著降低(t=12.376,P<0.001),N-cadherin(t=13.436,P<0.001)和Vimentin蛋白表达(t=11.467,P<0.001)显著升高;与葛根素+miR-490沉默模拟物+DTL阴性对照组相比,葛根素+miR-490沉默模拟物+DTL沉默质粒组E-cadherin蛋白表达显著升高(t=13.081,P<0.001),N-cadherin(t=10.835,P<0.001)和Vimentin蛋白表达(t=11.862,P<0.001)显著降低。结论 葛根素可能是通过上调miR-490表达,降低其靶基因DTL的表达,抑制非小细胞肺癌的生长、侵袭和迁移。

Puerarin Inhibits the Proliferation,Invasion,and Migration of Non-small Cell Lung Cancer Cells through Regulating miR-490/Denticleless E3 Ubiquitin Protein Ligase

Objective To explore the mechanism of puerarin inhibiting the proliferation,invasion,and migration of non-small cell lung cancer cells. Methods A549 cells were cultured and treated with different concentrations of puerarin.The inhibition rate (IR) on cell proliferation was detected by CCK-8,and qRT-PCR was performed to detect the mRNA levels of miR-490 and denticleless E3 ubiquitin protein ligase(DTL).Double luciferase reporter assay was employed to identify the targets of miR-490 and DTL based on the establishment of NC mimic group,miR-490 mimic group,NC inhibitor group,and miR-490 inhibitor group.The cells treated by 20 μmol/L puerarin were classified into six groups:DMSO,puerarin,puerarin+NC inhibitor,puerarin+miR-490 inhibitor,puerarin+miR-490 inhibitor+Si-NC,and puerarin+miR-490 inhibitor+Si-DTL.Transwell was used to detect cell migration and invasion.Western blotting was performed to detect the protein levels of epithelial-mesenchymal transition-related markers E-cadherin,N-cadherin,and Vimentin. Results With the increase in puerarin concentration,the IR gradually elevated (F=105.375,P<0.001),miR-490 expression gradually increased (F=32.919,P<0.001),and DTL expression gradually decreased (F=116.120,P<0.001).Compared with NC mimic group,miR-490 mimic group had decreased luciferase activity (t=7.762,P=0.016),raised miR-490 mRNA level (t=13.319,P<0.001),and declined DTL mRNA level (t=7.415,P=0.002).Compared with those in NC inhibitor group,miR-490 demonstrated decreased mRNA level (t=9.523,P=0.001) and DTL presented increased mRNA level (t=11.305,P<0.001) in miR-490 inhibitor group.Western blotting showed that the protein level of DTL was higher in NC mimic group (t=7.953,P=0.001) than in miR-490 mimic group and higher in miR-490 inhibitor group than in NC inhibitor group (t=10.552,P<0.001).Compared with DMSO group,puerarin group showed up-regulated mRNA level of miR-490 (t=10.255,P=0.001) while down-regulated mRNA level of DTL (t=6.682,P=0.003).Compared with those in puerarin+NC inhibitor group,the mRNA level of miR-490 declined (t=10.995,P<0.001) while that of DTL raised (t=12.478,P<0.001) in puerarin+miR-490 inhibitor group.The mRNA level of miR-490 had no significant difference between puerarin+miR-490 inhibitor+Si-NC group and puerarin+miR-490 inhibitor+Si-DTL group (t=1.081,P=0.341),and that of DTL was lower in the latter group (t=14.321,P<0.001).The protein level of DTL was higher in puerarin+miR-490 inhibitor group than in puerarin+NC inhibitor group (t=11.423,P<0.001),and lower in puerarin+miR-490 inhibitor+Si-DTL group than in puerarin+miR-490 inhibitor+Si-NC group (t=12.080,P<0.001).Compared with DMSO group,puerarin group showed inhibited cell proliferation (F=129.27,P<0.001).The activity of cell proliferation was higher in puerarin+miR-490 inhibitor group than in puerarin+NC inhibitor group (F=75.12,P<0.001),and higher in puerarin+miR-490 inhibitor+Si-NC group than in puerarin+miR-490 inhibitor+Si-DTL group (F=52.59,P<0.001).Compared with DMSO group,puerarin group had suppressed cell migration (t=8.963,P=0.001).The cell migration ability was higher in puerarin+miR-490 inhibitor group than in puerarin+NC inhibitor group (t=12.117,P<0.001) and higher in puerarin+miR-490 inhibitor+Si-NC group than in puerarin+miR-490 inhibitor+Si-DTL group (t=12.934,P<0.001).Puerarin group showed weakened cell invasion ability compared with DMSO group (t=4.710,P=0.009).The cell invasion ability was higher in puerarin+miR-490 inhibitor group than in puerarin+NC inhibitor group (t=13.264,P<0.001) and lower in puerarin+miR-490 inhibitor+Si-DTL group than in puerarin+miR-490 inhibitor+Si-NC group (t=13.476,P<0.001).Compared with DMSO group,puerarin group showed up-regulated protein level of E-cadherin (t=7.137,P=0.002) while down-regulated protein levels of N-cadherin (t=8.828,P=0.001) and vimentin (t=6.594,P=0.003).Compared with those in puerarin+NC inhibitor group,the protein level of E-cadherin (t=12.376,P<0.001) decreased while those of N-cadherin (t=13.436,P<0.001) and vimentin (t=11.467,P<0.001) increased in puerarin+miR-490 inhibitor group.Compared with puerarin+miR-490 inhibitor+Si-NC group,puerarin+miR-490 inhibitor+Si-DTL group up-regulated the protein level of E-cadherin (t=13.081,P<0.001) while down-regulated the protein levels of N-cadherin (t=10.835,P<0.001) and vimentin (t=11.862,P<0.001). Conclusion Puerarin could inhibit the proliferation,invasion,and migration of non-small cell lung cancer cells by up-regulating miR-490 and down-regulating DTL.