Selective secretion of microRNAs from lung cancer cells via extracellular vesicles promotes CAMK1D-mediated tube formation in endothelial cells

Abstract

Extracellular vesicles (EVs) are key signaling mediators between cancer cells and their supporting stroma, and regulate critical processes such as invasion, metastases, and angiogenesis. We have identified a subset of miRNAs (miR-142-3p, miR-143-3p, miR-145-5p, miR-150-5p, miR-223-3p, miR-451a, miR-486-5p, miR-605-5p) that are enriched in lung adenocarcinoma extracellular vesicles compared to the donor cells from which they were derived. Two well-known tumor suppressors, miR-143-3p and miR-145-5p, were also enriched in serum samples collected during surgery from blood vessels draining directly from lung adenocarcinoma tumor beds. Recently, both miRNAs were found to promote neoangiogenesis in endothelial cells in mouse models of lung adenocarcinoma through targeting of CAMK1D, an inhibitory kinase that can impair angiogenesis when over-expressed. We show that the transfer of miR-143-3p and miR-145-5p within extracellular vesicles from lung adenocarcinoma cells to endothelial cells reduces the levels of CAMK1D and increases tube formation by endothelial cells. This finding suggests that transfer of miRNAs within extracellular vesicles is a method of communication between cancer and endothelial cells which promotes angiogenesis while simultaneously removing tumor suppressive miRNAs within the tumor cells, thus driving tumorigenesis.

Extracellular vesicle secretion of miR‐142‐3p from lung adenocarcinoma cells induces tumor promoting changes in the stroma through cell‐cell communication

“…Previously we have demonstrated that miR‐142‐3p is selectively enriched by >4‐fold in the EVs derived from LAC cells compared to the donor cell . EV extraction was verified by Western blot for CD81 and TSG101 (Supplemental Figure S1).…”

“…EV extraction was verified by Western blot for CD81 and TSG101 (Supplemental Figure S1). Three of the five cell lines analyzed (H1437, H2073, H2228) did not have detectable quantities of miR‐142‐3p in the cellular RNA fraction, indicating a very efficient EV packaging mechanism as the EV's from these lines show enriched levels of miR‐142‐3p that accumulates in the donor cell when EV release is blocked . MiR‐142‐3p was detectable in the remaining intracellular fraction of cell lines (H1395 and H2347), but still showed a >18‐fold increase in the corresponding EVs .…”

“…Three of the five cell lines analyzed (H1437, H2073, H2228) did not have detectable quantities of miR‐142‐3p in the cellular RNA fraction, indicating a very efficient EV packaging mechanism as the EV's from these lines show enriched levels of miR‐142‐3p that accumulates in the donor cell when EV release is blocked . MiR‐142‐3p was detectable in the remaining intracellular fraction of cell lines (H1395 and H2347), but still showed a >18‐fold increase in the corresponding EVs . Using the established miR‐142 OE LAC cell lines we detected elevated miR‐142‐3p within the EVs by 3.4‐fold in H1437 cells and 5.1‐fold in H2073 cells compared to scramble miRNA mimic (miR‐C) paired lines.…”

“…We have previously shown that miR‐142‐3p is frequently enriched (>4‐fold compared to donor cell) in early LAC derived EVs . In LAC tissue miR‐142‐3p is reported to be down regulated by 2‐fold in 52% of cases .…”

miR‐605‐5p promotes invasion and proliferation by targeting TNFAIP3 in non–small‐cell lung cancer

“…Accumulating evidence has demonstrated that a large amount of exert critical effects on the progression and development of NSCLC. 8 miR-605-5p may enhance transactivation of p53 by inhibiting MDM2 in lung and breast cancer cell lines. 6 Accumulating evidence has shown the important role of miRNAs in cancer, including NSCLC, and suggests miRNAs to be biomarkers in NSCLC treatment.…”