[Human THP-1 macrophages activated by exosomes derived from lung adenocarcinoma cells promote lung cancer cell invasion].

Objective To examine the effect of exosomes derived from lung adenocarcinoma cells on macrophage polarization and the change of cytobiological behaviors in lung cancer cells induced by activated macrophages. Methods Exosomes derived from lung adenocarcinoma cells were extracted by exosomes extraction kit. The expression of exosomal markers including CD9 and CD63 was detected by Western blot analysis. After THP-1 cells were treated with 100 ng/mL phorbol ester (PMA) for 48 hours, the macrophage marker of CD68 was detected by real-time quantitative PCR (RT-qPCR). Following 24-hour treatment of macrophages with the exosomes (200 μg/mL), the mRNA levels of transforming growth factor β (TGF-β), tumor necrosis factor α (TNF-α), inducible nitric oxide synthase (iNOS) and CD163 were detected by RT-qPCR, and the protein levels of IL-6, IL-8 and IL-10 were measured by IMMULITE 1000. The macrophages after exosome treatment were co-cultured with A549 or H1299 cells. The invasion of lung adenocarcinoma cells was tested by TranswellTM assay and the mRNA levels of MMP9, MMP2 in lung adenocarcinoma cells were detected by RT-qPCR. Results CD9 and CD63 were highly expressed in exosomes. The THP-1 cells after PMA induction produced a high level of CD68. After the macrophages were treated with exosomes, the expression of iNOS decreased and the expression of CD163, TNF-α, IL-6, IL-8 and IL-10 significantly increased in the macrophages. The co-culture of macrophages with A549 and H1299 after exosome treatment enhanced significantly the invasion ability of lung adenocarcinoma cells and increased the levels of MMP2 and MMP9. Conclusion The exosomes derived from lung adenocarcinoma cells can activate macrophages to exhibit a mixed M1/M2 phenotype, thus promot the invasion of lung cancer cells.