Abstract: Objective To investigate the effects of 5-lipoxygenase activating protein (FLAP) inhibitor MK886 on the proliferation and apoptosis of human esophageal carcinoma cell lines (KYSE-150 and TE-3) and to explore the potential mechanism. Methods KYSE-150 and TE-3 cells were treated with MK886(2.5,5,10,20,40 and 80 μmol/L). xCELLigence RTCA system was used to to detect the half maximal inhibitory concentration(IC₅₀)of MK886. The expressions of proteins with apoptosis and autophagy were detected by Western blot and cell cycles were detected by flow cytometry. Results MK886 decreased the proliferation of human esophageal carcinoma cells(KYSE-150 and TE-3) (both P＜0.05).IC₅₀ of MK886 in KYSE-150 group was 29.11 μmol/L and in TE-3 group of 27.47 μmol/L.The proportion of G₀/G₁ phase was increased(both P＜0.001)However, in the group treated with concentrations of MK886 50 μmol/L,G₂/M phase was increased(P＜0.05). The expression of cleaved-caspase-3 and LC-3A/B-Ⅱwere increased with MK886 (both P＜0.001). Conclusions MK886 inhibits proliferation of human esophageal carcinoma cell lines and induces apoptosis.

Key words: esophageal carcinoma, proliferation, apoptosis, MK886, lipoxygenase