PTGS2 and lymphoma: Intriguingly, although the resulting lymphoma cells containing shAlox8-shPtgs2 as enriched GFP + cells in enlarged lymph nodes, these cells have upregulated Ptgs2 gene expression to a similar level as that in control shAlox8-shRen lymphoma cells (data not shown) and displayed similar histological features (Supplementary Fig. 3A, B), suggesting that shPtgs2 suppressive effect on Ptgs2 mRNA level had been bypassed or compensated during lymphomagenesis.