Identification of interleukin-1β regulated genes in uterine smooth muscle cells

We analyzed the response of uterine smooth muscle cells to interleukin-1 beta (IL-1 beta). We first showed that PHM1-31 myometrial cells, our cellular model, are contractile. To determine the molecular mechanisms of uterine smooth muscle cell activation by proinflarnmatory cytokines, we performed genechip expression array profiling studies of PHM1-31 cells in the absence and the presence of IL-1 beta. In total, we identified 198 known genes whose mRNA levels are significantly modulated (>2.0-fold change) following IL-1 beta exposure. We confirmed the expression changes for selected genes by independent mRNA and protein analysis. The group of genes induced by IL-1 beta includes transcription factors and inflammatory response genes such as nuclear factor of kappa light polypeptide gene enhancer in B-cells (NF kappa B), pentraxin-related gene (PTX3), and tumor necrosis factor alpha-induced protein 3/A20 (TNFAIP3/A20). We also found up-regulation of chemokines like C-X-C motif ligand 3 (CXCL3) and extracellular matrix remodeling signaling molecules like tenascin C (TNC). Our data suggest that IL-1 beta elicits the rapid activation of a cellular network of genes particularly implicated in inflammatory response that may create a cellular environment favorable for myometrial cell contraction. Our results provide novel insights into the mechanisms of uterine smooth muscle cell regulation and possibly infection-induced preterm labor.