Background: To investigate the therapeutic activity of the miR-221/222 inhibitor against OSCC in vitro and in vivo. Materials and Methods: HSC3 and HSC6 were treated with miR-221/222 inhibitor and the empty vector res...Background: To investigate the therapeutic activity of the miR-221/222 inhibitor against OSCC in vitro and in vivo. Materials and Methods: HSC3 and HSC6 were treated with miR-221/222 inhibitor and the empty vector respectively. After the recombinants were transfected into HSC3 and HSC6 with Lipofectamine<sup>TM</sup> MAX, the expression of miR-221/222 and PUMA was analyzed by RT-PCR. The proliferation and migration of HSC3 and HSC6 were detected by CCK-8 assay and Wound-healing assay. Cell cycle and apoptosis were detected by flow cytometry. The effect of the miR-221/222 inhibitor was also assessed in OSCC xenografts in BALB/c-nu mice. Results: Transfection of the miR-221/222 inhibitor increased cell apoptosis and upregulated PUMA expression in OSCC cell lines HSC3 and HSC6 with the significantly reduced expression of miR-221 and miR-222. Furthermore, the miR-221/222 inhibitor suppressed cell growth and invasion and blocked the cell cycle at the G1 phase. Obvious anti-tumor activity was achieved in BALB/c-nu mice by treatment with the miR-221/222 inhibitor, together with the upregulation of PUMA protein in tumors retrieved from the mice. Conclusions: There was a significant inhibitory effect of the miR-221/222 inhibitor on the growth of OSCC both in vitro and in vivo, and there might be a regulatory loop between miR-221/222 and PUMA. These findings demonstrated that downregulation of miR-221/222 could induce cell apoptosis, and it might be considered as a candidate target for gene therapy of OSCC.展开更多
微小RNA(microRNAs,miRNAs,)是一类强大的基因表达调控子,可在转录及转录后水平负调控靶基因的表达来参与生物学过程。沉默信息调节因子1(silent information regulator1,SIRT1)底物众多,可通过去乙酰化作用参与多种细胞生命活动进程。...微小RNA(microRNAs,miRNAs,)是一类强大的基因表达调控子,可在转录及转录后水平负调控靶基因的表达来参与生物学过程。沉默信息调节因子1(silent information regulator1,SIRT1)底物众多,可通过去乙酰化作用参与多种细胞生命活动进程。尽管如此,SIRT1与非编码RNA如miRNA的表达调控关系仍有待深入研究。本文利用荧光定量PCR检测发现,SIRT1与miR-221和miR-222的表达呈正相关:干扰SIRT1后,miR-221/222呈低水平表达;而过表达SIRT1则促进miR-221/222的表达。将miR-221/222基因簇启动子区序列插入p EZX-GA01构建双荧光素酶报告载体,与SIRT1过表达质粒或干扰序列共转至细胞。结果显示,SIRT1可显著提高miR-221/222启动子区活性,提示SIRT1可在转录水平调节miR-221/222的表达。进一步运用Western印迹研究发现,在HEK293细胞中过表达miR-221/222可促进细胞的自噬能力,而抑制miR-221/222的表达可减弱自噬。此外,过表达SIRT1的同时抑制miR-221/222的表达可减弱SIRT1的自噬诱导作用。综上所述,SIRT1可通过诱导miR-221/222的表达促进细胞自噬,其具体作用机制有待进一步探讨。展开更多
文摘Background: To investigate the therapeutic activity of the miR-221/222 inhibitor against OSCC in vitro and in vivo. Materials and Methods: HSC3 and HSC6 were treated with miR-221/222 inhibitor and the empty vector respectively. After the recombinants were transfected into HSC3 and HSC6 with Lipofectamine<sup>TM</sup> MAX, the expression of miR-221/222 and PUMA was analyzed by RT-PCR. The proliferation and migration of HSC3 and HSC6 were detected by CCK-8 assay and Wound-healing assay. Cell cycle and apoptosis were detected by flow cytometry. The effect of the miR-221/222 inhibitor was also assessed in OSCC xenografts in BALB/c-nu mice. Results: Transfection of the miR-221/222 inhibitor increased cell apoptosis and upregulated PUMA expression in OSCC cell lines HSC3 and HSC6 with the significantly reduced expression of miR-221 and miR-222. Furthermore, the miR-221/222 inhibitor suppressed cell growth and invasion and blocked the cell cycle at the G1 phase. Obvious anti-tumor activity was achieved in BALB/c-nu mice by treatment with the miR-221/222 inhibitor, together with the upregulation of PUMA protein in tumors retrieved from the mice. Conclusions: There was a significant inhibitory effect of the miR-221/222 inhibitor on the growth of OSCC both in vitro and in vivo, and there might be a regulatory loop between miR-221/222 and PUMA. These findings demonstrated that downregulation of miR-221/222 could induce cell apoptosis, and it might be considered as a candidate target for gene therapy of OSCC.
文摘微小RNA(microRNAs,miRNAs,)是一类强大的基因表达调控子,可在转录及转录后水平负调控靶基因的表达来参与生物学过程。沉默信息调节因子1(silent information regulator1,SIRT1)底物众多,可通过去乙酰化作用参与多种细胞生命活动进程。尽管如此,SIRT1与非编码RNA如miRNA的表达调控关系仍有待深入研究。本文利用荧光定量PCR检测发现,SIRT1与miR-221和miR-222的表达呈正相关:干扰SIRT1后,miR-221/222呈低水平表达;而过表达SIRT1则促进miR-221/222的表达。将miR-221/222基因簇启动子区序列插入p EZX-GA01构建双荧光素酶报告载体,与SIRT1过表达质粒或干扰序列共转至细胞。结果显示,SIRT1可显著提高miR-221/222启动子区活性,提示SIRT1可在转录水平调节miR-221/222的表达。进一步运用Western印迹研究发现,在HEK293细胞中过表达miR-221/222可促进细胞的自噬能力,而抑制miR-221/222的表达可减弱自噬。此外,过表达SIRT1的同时抑制miR-221/222的表达可减弱SIRT1的自噬诱导作用。综上所述,SIRT1可通过诱导miR-221/222的表达促进细胞自噬,其具体作用机制有待进一步探讨。