Deng Wei, Yan Mingxia, Yu Tao, Ge Haiyan, Lin Hechun, Li Jing, Liu Ying, Geng Qin, Zhu Miaoxin, Liu Lei, He Xianghuo, Yao Ming
State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Cell Physiol Biochem. 2015;35(5):1677-88. doi: 10.1159/000373981. Epub 2015 Mar 18.
microRNAs can repress the expression of target genes by destabilizing their mRNAs or by inhibiting their translation. Our previous findings suggested that miR-193a-3p inhibited the progression of NSCLC both in vitro and in vivo. However, the biological processes and molecular pathways through which this miRNA exerts its positive effects are unknown.
To explore the molecular mechanisms by which miR-193a-3p inhibited NSCLC metastasis, we investigated the changes in the protein profile of SPC-A-1sci (highly metastatic) cells in response to the up-regulation of miR-193a-3p expression using a proteomics approach (iTRAQ combined with NanoLC-MS/MS). Changes in the profiles of the expressed proteins were verified using western blotting and were analyzed using the DAVID and STRING programs.
In the two replicated experiments, 4962/4946 proteins were identified, and the levels of expression of 4923/4902 proteins were quantified. In total, 112 of these proteins were differentially expressed. Among them, the up-regulated levels of expression of two of the 62 proteins with up-regulated expression (PPP2R2A and GSN) and the down-regulated levels of expression four of the 50 proteins with down-regulated expression (LMNB2, UHRF1, G3BP1, and HNRNPU) were verified using western blotting. The bioinformatics analysis revealed the interactions and signaling networks of these differentially expressed proteins.
miR-193a-3p inhibited the metastasis of lung cancer cells by deregulating the expression of tumor-related proteins. These findings may improve the understanding of the molecular mechanisms underlying the metastatic-inhibitory effect of miR-193a-3p on lung cancer cells.
微小RNA可通过使靶基因的信使核糖核酸（mRNA）不稳定或抑制其翻译来抑制靶基因的表达。我们之前的研究结果表明，miR-193a-3p在体外和体内均抑制非小细胞肺癌（NSCLC）的进展。然而，这种微小RNA发挥其积极作用的生物学过程和分子途径尚不清楚。
为了探究miR-193a-3p抑制NSCLC转移的分子机制，我们采用蛋白质组学方法（同位素标记相对和绝对定量技术结合纳升级液相色谱-串联质谱技术）研究了SPC-A-1sci（高转移性）细胞中miR-193a-3p表达上调后蛋白质谱的变化。使用蛋白质免疫印迹法验证表达蛋白谱的变化，并使用DAVID和STRING程序进行分析。
在两次重复实验中，共鉴定出4962/4946种蛋白质，并对4923/4902种蛋白质的表达水平进行了定量。其中共有112种蛋白质差异表达。其中，通过蛋白质免疫印迹法验证了62种表达上调的蛋白质中有2种（蛋白磷酸酶2调节亚基Bβ亚型（PPP2R2A）和凝溶胶蛋白（GSN））表达上调，50种表达下调的蛋白质中有4种（核纤层蛋白B2（LMNB2）、泛素样含PHD和指环结构域蛋白1（UHRF1）、 RasGTP酶激活蛋白1（G3BP1）和不均一核糖核蛋白U（HNRNPU））表达下调。生物信息学分析揭示了这些差异表达蛋白质的相互作用和信号网络。
miR-193a-3p通过调节肿瘤相关蛋白的表达来抑制肺癌细胞的转移。这些发现可能有助于加深对miR-193a-3p对肺癌细胞转移抑制作用潜在分子机制的理解。
