靶向调控LASP1基因miRNAs分子的鉴定及其在结直肠癌转移中的作用机制

Our previous research has identified LASP1 as a novel colorectal carcinoma (CRC) metastasis-associated protein, which up-regulated in CRC and closely related with tumor metastsis poor prognosis. The regulatory mechanisms of LASP1 abnormal expression, however, are still not clear. Recently, using bioinformatic methods and pre-trial results in vitro, we showed that miR-1, miR-133a, miR-206, miR-29b and miR-29c may interact with LASP1 3'UTR and regulate LASP1 expression. Transient transfection of their miRNAs mimics may decreased LASP1 protein expression at a different degree. Based on that, using qRT-PCR, in situ hybridization histochemistry, dual-luciferase reporter gene assay, miRNA transfection, miRNA inhibition, cell biological function in vivo/in vitor and proteomic techniques, the project identify most effective miRNAs targeting LASP1 and illustrate its regulatory mechanism. The study may uncover molecular mechanism of LASP1 underlying CRC metastais at a post-transcriptional level and provide new strategies for prevention and therapy and novel target for durg discovery of CRC metastasis.

本课题组前期研究证明LASP1是一个新的结直肠癌转移相关蛋白，在结直肠癌中高表达，与结直肠癌转移及不良预后密切相关，但其异常表达的调控机制尚不清楚。最近，我们通过综合利用生物信息学方法逆向预测并结合体外预实验研究结果，预测miR-1、miR-133a、miR-206、miR-29b和miR-29c五种miRNAs可能与LASP1基因3'UTR结合并调控其表达；瞬时转染五种miRNAs mimic后，LASP1蛋白表达均有不同程度的下调。在此基础上，本项目拟采用qRT-PCR、原位杂交、荧光素酶报告基因系统、miRNA转染、表达阻断、体内外细胞生物学功能分析、蛋白质组学技术等手段，鉴定出靶向调控LASP1的最有效miRNAs及其调控作用机制，在转录后层面揭示LASP1在结直肠癌转移中作用的分子机制，为结直肠癌转移的预防和治疗提供新的策略，并为药物筛选提供新的靶点。

LASP1（LIM and SH3 protein 1）是我们前期通过蛋白质组学研究筛选并鉴定的结直肠癌转移相关蛋白，在结直肠癌中表达上调，并与肿瘤转移及不良预后密切相关。许多研究已经证实LASP1在肿瘤中的关键作用，但其异常表达及促进肿瘤转移的机制目前尚不清楚。本项目通过系列研究明确miR-1和miR-133a能通过靶向LASP1 3’UTR区域调控LASP1的表达，而LASP1能在转录水平调节S100A4的表达，通过smad和非smad信号通路途径，参与TGFβ1诱导的肿瘤上皮间质转化（EMT），促进结直肠癌的转移。相关研究共发表SCI论文7篇，累计影响因子32.256，单篇最高影响因子8.722.