PTGS2 and lung large cell carcinoma: Interestingly, our finding that antagonism of the PGE2 receptor decreased COX-2-mediated VEGF up-regulation in NSCLC cells, especially in H460 large-cell lung cancer cells, confirms that PGE2, a downstream product of COX-2 activity, may participate in COX-2-mediated VEGF up-regulation.