In fact, 48 h after infection with invasive InvColi strains transformed with shCOX-2-expressing vectors (InvColi-pSH1, InvColi-pSCOX−2 and InvColi-pSTBE), we started to observe a significant reduction in COX-2 protein and mRNA levels in HT-29 and HCA-7 cells (Figure 3D and E). The gene discussed is PTGS2; the disease is infection.