中文摘要：

目的 制备并筛选靶向鼠结直肠癌细胞株CT-26增殖诱导配体（APRIL）基因小干扰RNA（siRNA）,通过检测APRIL siRNA抑制肠癌细胞生长及迁移等指标,为体内递送APRIL siRNA靶向治疗小鼠结直肠癌原位模型奠定基础.方法 分别设计、合成4种不同位点的APRIL siRNA,同时以合成无序序列作为阴性对照,再用LipofectAMINE 2000转染高表达APRIL的鼠结直肠癌细胞株CT-26,荧光显微镜下计数评价6-FAM标记的APRIL siRNA转染效率与筛选转染浓度 FQ-RT-PCR检测APRIL mRNA水平,Western印迹分析APRIL蛋白表达,筛选沉默效率最高的APRIL siRNA片段 细胞损伤修复法检测APRIL siRNA抑制肠癌细胞迁移的能力 CCK-8（cell counting kit-8）法检测细胞增殖情况 RT-PCR检测基质金属蛋白酶MMP-2及TIMP-1 mRNA水平.结果 4种不同siRNA瞬时转染CT-26细胞后APRIL mRNA和蛋白表达有明显差别（P＜0.05）.APRIL siRNA组与对照组相比,细胞生长与迁移能力明显减弱（P＜0.05）,MMP-2及TIMP-1 mRNA水平均有显著性差别（P＜0.05）.结论 成功筛选靶向鼠结肠癌细胞株CT-26增殖诱导配体APRIL siRNA,其中APsi737敲低效率可达到90%.靶向APRIL基因小干扰RNA可有效降低肠癌细胞的生长与转移能力,可能与MMP-2及TIMP-1的调节有关.可用于后续的靶向治疗结直肠癌研究.

英文摘要：

Objective To construct and screen siRNA targeting a proliferation-inducing ligand （APRIL） gene in a mouse colorectal cancer celline, CT-26. To investigate the effects to the cell growth and migrant capacity of CT-26 after knockdown APRIL gene, lay the foundation for molecular targeted therapy to colorectal cancer. Methods Four pairs of APRIL siRNA were designed and chemically synthesized. And disorder sequences were synthesized as a negative control. These sequences were transfected with LipofectAMINE 2000 into CT-26 cells, which high-expressed APRIL gene. The transfection efficency rate of 6-FAM labelled control siRNA was detected by fluorescence microscope. The inhibition effectiveness of APRIL mRNA and protein was analyzed by FQ-RT-PCR and Western blot, respectively. Cell proliferation activity was analyzed by cell counting kit-8, cell migration capacity was detected by the repair of cell damage, and MMP-2 together with TIMP-1, two important regulatory genes in cell metastasis, were measured by RT-PCR.Results The different kinds of APRIL siRNA effectively suppressed the level of APRIL mRNA and the protein expression in CT-26 （P 〈 0.05 ）. Cell proliferation and metastasis ability were repressed after APRIL siRNA transfection（ P 〈 0.05 ）, compared with random siRNA control and nontransfected control. The mRNA levels of MMP-2 and TIMP-1 genes wre significantly altered among APRIL siRNA groups and two control groups （ P 〈 0.05）. Conclusion We have constructed and screened a kind of siRNA （APsi737） targeting APRIL gene in a mouse colorectal cancer cell line, CT-26. APRIL siRNA can effectively inhibit the cell growth and migration capacity, maybe be regulated by MMP-2 and TIMP-1.