At MOI 1:100, bacterial infection rapidly induced COX-2 overexpression in HT-29pS(−) cells (days 1–4), most probably due to the higher presence of LPS (Hla and Neilson, 1992), but we did not observe this phenomenon in HT-29pS(shCOX−2) cells (Figure 7C). The gene discussed is PTGS2; the disease is bacterial infectious disease.