M2 macrophages-derived exosomal miR-3917 promotes the progression of lung cancer via targeting GRK6.

Macrophages in the tumor microenvironment (TME) can serve as potential targets for therapeutic intervention. The aim of this study was to investigate the molecular mechanism by which M2 macrophage-derived exosomes (M2-Ex) affect lung cancer progression through miRNA transport. The THP-1 cells were differentiated into M0 and M2 macrophages. M2-Ex were isolated and identified by transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). Cancer tissues and adjacent tissues of non-small-cell lung cancer (NSCLC) patients were collected. H1299 and A549 cells were co-cultured with M2-Ex. Subcutaneous xenograft mouse model was established. miR-3917 is highly expressed in lung cancer tissues and M2-Ex. Interference of miR-3917 in M2-Ex inhibits H1299 cell proliferation, migration and invasion, while overexpression of miR-3917 had the opposite effect in A549 cells. M2-Ex promote tumor growth by delivering miR-3917 in vivo. miR-3917 could target G protein-coupled receptor kinase 6 (GRK6), and interference of miR-3917 in M2-Ex inhibits H1299 cells proliferation, migration and invasion by up-regulating GRK6 level, while overexpression of miR-3917 had the opposite effect in A549 cells. M2-Ex can transfer miR-3917 into lung cancer cells and promote lung cancer progression, providing theoretical basis for the diagnosis and effective treatment of lung cancer.

ELANE Promotes M2 Macrophage Polarization by Down-Regulating PTEN and Participates in the Lung Cancer Progression.

BACKGROUND: Macrophages are one of the most important immunoinflammatory cell populations in the tumor microenvironment (TME). In this study, we preliminarily investigated the upstream pathway of M2 macrophage polarization affecting lung cancer progression. METHODS: Bioinformatics analysis was used to evaluate genes closely associated with lung adenocarcinoma and their relationship with immune cells. THP-1 monocytes were induced into M2 macrophages. The expression of markers in M2 macrophages was detected by quantitative reverse transcription-PCR (qRT-PCR), enzyme linked immunosorbent assay (ELISA), and flow cytometry. The effects of neutrophil elastase (ELANE)-mediated M2 macrophages on lung cancer cell proliferation, migration and invasion and tumor growth were investigated by in vitro and in vivo experiments after co-culture of macrophage conditioned medium (CM) and lung cancer cell lines A549 and H1299. The PTEN protein expression was detected by Western blotting. RESULTS: ELANE was significantly positively correlated with M2 macrophages. ELANE up-regulated the expression of the M2 macrophage markers CD206, CCL22, IL-10 and CCL18 and increased the proportion of CD206+ macrophages. Compared with M0-CM, M2-CM promoted cell proliferation, migration, and invasion, and (M2+ELANE)-CM further enhanced this effect. In vivo, ELANE promoted M2 macrophage-induced tumor growth in lung cancer mice model. In vitro experiments showed that ELANE can down-regulate the expression of PTEN and promote the polarization of M2 macrophages. CONCLUSION: ELANE promotes the polarization of M2 macrophages by down-regulating PTEN, thus promoting cell proliferation, migration, and invasion in vitro and growth of lung cancer cells in vivo.

Up-regulation of CKAP2L expression promotes lung adenocarcinoma invasion and is associated with poor prognosis.

AIM: The purpose of this study is to consider the function of cytoskeleton-associated protein 2-like (CKAP2L) in lung adenocarcinoma (LAD) development and its prognostic value. METHODS: The mRNA expression of CKAP2L and its correlation with clinical factors in LAD patients were analyzed from the data taken from The Cancer Genome Atlas and The First Affiliated Hospital of Kunming Medical University. We constructed H460 and A549 cell lines with silenced CKAP2L using RNA interference. Cell counting kit-8 assay and colony formation assays were carried out to determine the function of CKAP2L in H460 and A549 cell proliferation. Transwell and wound healing assays were applied to determine the effect of CKAP2L on H460 and A549 cell invasion and migration. The influences of CKAP2L on mitogen-activated protein kinase signaling pathway-related proteins were tested by Western blotting. RESULTS: CKAP2L expression is enhanced in LAD tissues and is predictive of poor prognosis in LAD patients. High expression of CKAP2L is associated with stage (P<0.001), lymph node status (P=0.002), and metastasis (P=0.025). Depletion of CKAP2L dramatically suppressed the proliferation, migration, and invasion of H460 and A549 cells. Moreover, the ratio of p-MEK/ MEK and p-ERK/ERK reduced obviously in A549 cells after depleting CKAP2L. CONCLUSION: Our findings implied that CKAP2L might be a promoter of LAD and could serve as a predictor for LAD patients.