Trials in xenograft tumor models have shown that selective COX-2 inhibitors can inhibit the growth of lung cancer cells and enhance the efficacy of chemotherapy for NSCLC.26 Additionally, our previous study, which has been published, reported that COX-2 inhibitors combined with chemotherapy might partially improve the PFS of patients with advanced NSCLC.32 Celecoxib in combination with TKIs prolongs PFS, which is consistent with the results of a phase II clinical trial evaluating erlotinib combined with celecoxib. Here, PTGS2 is linked to lung cancer.