Abstract: Objective To investigate the role of miR-146a in regulating cytokine expression and the possible underlying mechanisms involved. Methods miR-146a mimics or inhibitor were transfected into human acute monocytic leukemia cell line (THP-1 cell line) by lentiviral vectors, and THP-1 cell in normal culture were used as control group. The expression levels of AUF1 in THP-1 cell lines were dectected by real-time PCR and Western blot. The levels of interleukin-8(IL-8) and interleukin-35(IL-35) in the culture supernatant were dectected by ELISA. Results miR-146a mimics decreased, while miR-146a inhibitor did not affect the expression of AUF1 in IL-1β-induced THP-1 cell lines. In addition, miR-146a mimics decreased（P<0.01; P<0.05）, while miR-146a inhibitor increased（P < 0.01；P < 0.01）, the expression of inflammatory cytokine IL-8 and anti-flammatory cytokine IL-35. Conclusions AUF1 is one of targets of miR-146a. miR-146a regulates the pro-inflammatory cytokine IL-8 secretion, which is accompanied by anti-flammatory cytokine IL-35.

Key words: THP-1 cell lines, MicroRNA-146a, AUF1, Cytokine