To determine whether CS-6 also inhibited COX-2 expression in other NSCLC cells, we treated H322 and H460 cells with CS-6 at different doses, and found that CS-6 also considerably suppressed COX-2 protein expression in both H322 and H460 cells.To further confirm the role of CS-6 in regulating the COX-2 signaling in lung cancer cells, A549 cells were treated with CS-6 (50 nM) after COX-2-selective inhibitor celecoxib (CB, 25 uM and 50 uM) pretreatment at 8 h. The gene discussed is PTGS2; the disease is lung carcinoma.