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目的:探讨癌相关成纤维细胞(CAFs)来源外泌体微小RNA(miR)-20a对前列腺癌细胞间通讯连接(GJIC)、侵袭和转移能力的影响及其机制。方法:构建CAFs来源近红外荧光蛋白(IRFPs)标记外泌体，以不同浓度(0、10、100、200 mg/L)与PC-3细胞共培养。蛋白质印迹法检测PC-3细胞中CX43蛋白的相对表达水平；荧光漂白恢复技术测定PC-3细胞间缝隙连接功能；Transwell小室侵袭和迁移实验检测PC-3侵袭能力。构建高表达和低表达miR-20a的CAFs，分别与PC-3细胞共培养，检测缝隙链接蛋白43(Connexin 43, CX43)表达、细胞缝隙连接功能、细胞迁移和侵袭能力。双荧光素酶报告实验验证PC-3细胞中miR-20a与CX43基因是否直接结合。用Student’n t检验分析组间差异。n 结果:PC-3细胞的CX43表达水平及细胞缝隙连接功能均随外泌体浓度增加而降低(0.715±0.058、0.544±0.039、0.313±0.028和0.196±0.020，n F＝19.031，n P<0.05)，差异有统计学意义。Transwell小室检测结果表明，CAFs来源外泌体促进PC-3细胞迁移[各组每视野穿膜细胞数分别为(176.0±9.2)、(485.0±12.8)、(159.5±9.7)和(198.0±10.5)个，n F＝11.475，n P<0.01]和侵袭[各组每视野穿膜细胞数分别为(150.0±8.4)、(443.0±21.7)、(182.0±11.2)和(153.5.0±10.1)个，n F＝16.306，n P<0.01]，差异有统计学意义；增强细胞缝隙连接能抑制此效应(n F＝14.052，n P<0.01；n F＝14.804，n P<0.01)。高表达miR-20a组的PC-3细胞的CX43表达水平(0.126±0.062比0.834±0.103，n t＝9.430，n P<0.05)、荧光恢复率[(25.02±7.85)%比(46.65±6.98)%，n t＝5.782，n P<0.05]均显著低于低表达miR-20a组，但细胞的迁移[(502.5±18.6)个比(128.5.0±9.4)个，n t＝9.120，n P<0.05]和侵袭能力(458.0±16.8比194.5±9.2，n t＝6.286，n P<0.05)均显著高于表达miR-20a组，差异均有统计学意义。双荧光素酶报告实验结果显示，野生型CX43的PC-3细胞中，转染miR-20a的细胞荧光活性显著低于miR-NC组(0.46±0.08比0.99±0.14，n t＝10.208，n P0.05)。n 结论:CAFs来源外泌体miR-20a通过直接作用CX43基因，下调PC-3细胞CX43的表达，从而显著降低细胞间通讯连接功能，增强前列腺癌细胞的增殖、侵袭和转移能力。“,”Objective:To explore the effects and mechanism of exosomes microRNA (miR)-20a secreted by carcinoma-associated fibroblasts (CAFs) on gap junction intercellular communication (GJIC) and the ability to invasion and metastasis of prostate cancer cells. Student′s n t test was used to analyze the differences between groups.n Methods:Exosomes marked by near-infrared fluorescent protein (IRFPs) from CAFs were extracted and were co-cultured with PC-3 cells at a variety of concentrations (0, 10, 100, 200 μg/ml). Western blotting was used to detect relative expression level of connexin 43 (CX43) protein in PC-3 cells. The function of GJIC in PC-3 cells was measured using fluorescence photobleaching recovery (FRP). Transwell assays were conducted to assess invasive capacity. CAFs with high and low expression level of miR-20a were constructed and were co-cultured with PC-3 cells separately to determine the expression of CX43, the function of GJIC and migratory and invasive abilities. Dual-luciferase reporter assay was performed to verify whether miR-20a was bound to CX43 gene directly.Results:Expression level of CX43 and the function of GJIC in PC-3 cells decreased with increasing exosomes concentrations (0.715±0.058, 0.544±0.039, 0.313±0.028 and 0.196±0.020, n P<0.05). Transwell assays revealed that exosomes from CAFs promoted migration (the number of transmembrane cells in each field of vision in each group was 176.0±9.2, 485.0±12.8, 159.5±9.7 and 198.0±10.5,n t=11.475, n P<0.01) and invasion (the number of transmembrane cells in each field of vision in each group was 150.0±8.4, 443.0±21.7, 182.0±11.2 and 153.5.0±10.1,n t=16.306, n P<0.01) of PC-3 cells. However, the enhancement of GJIC functions could inhibit this effect (n t=14.052, n P<0.01;n t=14.804, n P<0.01). The expression level of CX43 (0.126±0.062 vs. 0.834±0.103,n t=9.430, n P<0.05), fluorescence recovery [(25.02±7.85)% vs. (46.65±6.98)%,n t=5.782, n P<0.05] of PC-3 cells in the group treated with exosomes over-expressing miR-20a were significantly reduced, and the migratory (502.5±18.6 vs. 128.5.0±9.4,n t=9.120, n P<0.05) and invasive (458.0±16.8 vs. 194.5±9.2,n t=6.286, n P<0.05) capabilities of PC-3 cells in the group treated with exosomes over-expressing miR-20a were significantly promoted as compared with the group treated with exosomes silencing miR-20a. Dual-luciferase reporter assay demonstrated that PC-3 cells with wild type-CX43, transfected with miR-20a had a significantly lower fluorescence than the cells treated with miR-NC (0.46±0.08 vs. 0.99±0.14,n t=10.208, n P0.05).n Conclusion:Exosomes miR-20a secreted by CAFs downregulated the expression level of CX43 in PC-3 cells by the direct combination with CX43 gene, resulting in significant attenuation of the function of GJIC, which can augment proliferation, invasion and metastasis of prostate cancer cells.