To understand the specific exo-miRNAs involved in COX-2-mediated CAFs activation, we detected the expressions of 26 most common oncogenic miRNAs in lung cancer cells after treatment with COX-2 overexpression, and found that miR-1290 level was upreguated by COX-2, increasing about 100-fold in both cancer cells and exosomes. Here, PTGS2 is linked to lung cancer.