PTGS2 and cancer: Mature MDDC from cancer patients as well as from healthy donors up-regulated the frequency of COX-2+ cells in response to LPS (cancer group, p = 0.01; healthy group, p = 0.02) and IFN-γ+LPS stimulation (cancer group, p = 0.02; healthy group, p = 0.004) compared to the respective unstimulated controls (data not shown).