目的：探讨MicroRNA（miR）-135a对Ras家族小G蛋白2a（Rap2a）下游p-Akt表达及肾细胞癌（RCC）细胞迁移侵袭的影响，深入了解RCC恶化的潜在机制。方法：采用蛋白质印迹法检测正常肾组织细胞HK-2与RCC细胞Ketr-3、786-O、ACHN中Rap2a的表达水平；Target Scan软件预测靶向调控Rap2a的潜在miRNAs；双荧光素酶报告基因实验检测miR-135a与Rap2a基因的靶向关系；蛋白质印迹法检测Ketr-3细胞中Rap2a及其下游信号蛋白磷酸化蛋白激酶B（phosphate protein kinase B，p-Akt）表达；侵袭小室实验检测Ketr-3细胞的迁移侵袭能力。结果：Rap2a在正常肾组织细胞HK-2中低表达，在RCC细胞系中显著高表达；Target Scan软件预测发现miR-135a可与Rap2a的3'UTR互补结合；双荧光素酶报告基因检测与蛋白质印迹法实验均证实了miR-135a与Rap2a间的相互作用；过表达miR-135a可通过降低Rap2a及其下游蛋白p-Akt的表达抑制Ketr-3细胞的迁移侵袭能力。结论：本研究揭示了miR-135a通过靶向Rap2a/Akt信号途径抑制RCC细胞的迁移侵袭能力，miR-135a和Rap2a可能是治疗RCC的潜在分子靶点。

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