Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Cancer Immunol Immunother. 2021 May;70(5):1323-1339. doi: 10.1007/s00262-020-02762-x. Epub 2020 Nov 3.
In the tumor microenvironment, macrophages polarize into the M2 phenotype to facilitate tumorigenesis. Tumor-derived exosomes can act as mediators between the tumor microenvironment and stromal cells by transporting proteins, mRNAs, and miRNAs. Exosomal miRNAs play a pivotal role in modulating tumor microenvironment and macrophage polarization. Here, we overexpressed miR-130 and miR-33 in exosomes of MDA-MB-231 cells and investigated their effect on macrophage polarization and tumor progression. For this purpose, exosomes were extracted from MDA-MB-231 cells and characterized using dynamic light scattering, electron microscopy, and western blotting of exosomal markers. Then, miR-130 or miR-33 containing exosomes were used to treat IL4-induced M2 or tumor-associated macrophages (TAMs). After treatment, the polarization status of macrophages, including the expression of M1 specific genes, and the secretion of cytokines were evaluated. Finally, the conditioned medium from exosome-treated macrophages was incubated with cancer cells to evaluate its effect on the migration and invasion ability of cancer cells and, in vivo experiments investigated the effect of exosome-treated macrophages on breast cancer progression. Exosomes characterization results approved the range of size and homogeneity of extracted exosomes. Overexpression of miR-130 and miR-33 in exosomes increased the expression of M1 signature genes (IRF5, MCP1, CD80) and secretion of cytokines (IL-1β and TNF-α) as well as yeast phagocytic activity of macrophages. Besides, the conditioned medium of macrophages treated with miRNA containing exosomes declined the migration and invasion ability of cancer cells. The in vivo results indicated the inhibitory effect of exosome-treated macrophages on tumor growth. Furthermore, the results showed that in response to exosome-treated macrophages, the production of TNF-α by spleen cells increased, while the production of IL-10 and TGF-β by these cells decreased. These findings suggest that overexpression of miR-130 and miR-33 in exosomes can decrease tumor progression by shifting macrophage polarization from M2 to M1 phenotype and can be a potential therapeutic strategy for tumor interventions.
在肿瘤微环境中，巨噬细胞极化为 M2 表型以促进肿瘤发生。肿瘤衍生的外泌体可以通过运输蛋白质、mRNA 和 miRNA 作为肿瘤微环境和基质细胞之间的介质。外泌体 miRNA 在调节肿瘤微环境和巨噬细胞极化中发挥关键作用。在这里，我们在 MDA-MB-231 细胞的外泌体中过表达 miR-130 和 miR-33，并研究了它们对巨噬细胞极化和肿瘤进展的影响。为此，从 MDA-MB-231 细胞中提取外泌体，并通过动态光散射、电子显微镜和外泌体标志物的 Western blot 进行表征。然后，用含有 miR-130 或 miR-33 的外泌体处理 IL4 诱导的 M2 或肿瘤相关巨噬细胞（TAMs）。处理后，评估巨噬细胞的极化状态，包括 M1 特异性基因的表达和细胞因子的分泌。最后，用外泌体处理的巨噬细胞的条件培养基孵育癌细胞，以评估其对癌细胞迁移和侵袭能力的影响，并进行体内实验研究外泌体处理的巨噬细胞对乳腺癌进展的影响。外泌体特征化结果证实了提取外泌体的大小范围和均一性。外泌体中 miR-130 和 miR-33 的过表达增加了 M1 特征基因（IRF5、MCP1、CD80）的表达和细胞因子（IL-1β 和 TNF-α）的分泌以及巨噬细胞的酵母吞噬活性。此外，用含有 miRNA 的外泌体处理的巨噬细胞的条件培养基降低了癌细胞的迁移和侵袭能力。体内结果表明，外泌体处理的巨噬细胞对肿瘤生长具有抑制作用。此外，结果表明，与外泌体处理的巨噬细胞反应后，脾细胞产生的 TNF-α增加，而这些细胞产生的 IL-10 和 TGF-β减少。这些发现表明，外泌体中 miR-130 和 miR-33 的过表达可以通过将巨噬细胞从 M2 表型极化到 M1 表型来减少肿瘤进展，并且可以成为肿瘤干预的潜在治疗策略。
