Ran JJ, Li Y, Liu L, et al. - Researchers investigated if proliferation as well as invasion ability of lung cancer cells is intensified by apelin by way of exosomal microRNA (miRNA). By lentiviral transfection, they generated lung cancer A549 cells that were overexpressing apelin and control vector. From the culture supernatant of each cell group, they isolated and described exosomes. Experts identified that more A-exo was absorbed by A549 cells than V-exo. Proliferation, colony formation, migration and invasion of A549 cells was better promoted by A-exo vs V-exo. They discovered miR-15a-5p was distinctly lower in A-exo vs V-exo, as seen in exosomal miRNA-sequencing data; it's been suggested that miR-15a-5p may have an anti-tumor role since its low expression has been seen in lung cancer tissues and cell lines. This study supported the existance of a novel regulatory mechanism of apelin, via inhibiting miR-15a-5p encapsulated in exosomes, may enhance proliferation as well as invasion of lung cancer cells.