miR-194 retards LPS-induced lung cell inflammation by downregulating CXCR4. Macrophages exposed to LPS were treated with miR-194/NC mimic alone or in the presence of oe-NC/CXCR4. a Expression of miR-194 in the transfected cells measured by RT-qPCR; b mRNA and protein expression of CXCR4 measured by RT-qPCR and western blot analysis, respectively; c Expression of inflammatory factors IL-1β, IL-6 and TNF-α in the transfected cells detected by ELISA; d MPO activity in the transfected cells. The data in the figures were all measurements, which were expressed as mean ± standard deviation; data between different groups were compared by unpaired t-test. *, p < 0.05.