PTX3 and systemic sclerosis: Microarray results indicated that cyclooxgenase 1/prostaglandin synthase 1 (COX1/PTGS1) and cyclooxygenase 2/prostaglandin synthase 2 (COX2/PTGS2), important mediators of arachidonic acid and prostaglandin synthesis were strongly downregulated in untreated SSc-derived fibroblasts compared to normal untreated fibroblasts as were matrix metalloproteinase 3 (MMP3), pentraxin-3 (PTX3) and suppressor of cytokine signaling 2 (SOCS2).