N-Isopropylacrylamide-modified polyethylenimine-mediated miR-29a delivery to inhibit the proliferation and migration of lung cancer cells

MicroRNAs have been identified as a promising tool in cancer gene therapy, and an efficient and safe gene carrier was significantly required in the clinical application of miRNAs. Herein, a polyethylenimine (PEI) derivative, N -isopropylacrylamide-modified PEI (namely PEN), was constructed through Michael addition and then employed as a carrier for miR-29a transfection. The carrier PEN has been demonstrated to possess favorable ability to condense miR-29a into stable nanoparticles and protect miR-29a against the nuclease degradation, using agarose gel retardation assay. Meanwhile, PEN exhibited excellent efficiency in miR-29a transfection demonstrated by flow cytometry and confocal laser scanning microscope. Further, the PEN-mediated miR-29a transfection could achieve an obvious anti-proliferative effect owing to the activation of cell apoptosis and the cell cycle arrest at G1 phase, using human lung adenocarcinoma cell line A549 as a model. In addition, PEN/miR-29a nanoparticles could suppress the migration and invasion of cancer cells measured by wound healing and Transwell migration assays. Overall, the PEN-mediated miR-29a transfection could be potentially employed as a useful approach to achieve cancer gene therapy.