RESUMO
Objective To investigate the effects of down-regulation of lemur tyrosine kinase 3 (LMTK3) on the cytobiological behaviors of human lung cancer A549 cells.Methods The expression of LMTK3 in A549 cells was interfered with small hair RNA (shR-NA),and the expression level of LMTK3 was determined by RT-PCR.The effects of LMTK3 on the proliferation,migration,cell cycle and apoptosis of A549 cells were determined by the CCK-8 assay,scratch assay,Transwell assay and flow cytometry,respectively.Results The shLMTK3 cells with stably low expression of LMTK3 and control cells (Scramble) with normal expression of LMTK3 were successfully obtained.The relative proliferation rates of shLMTK3 cells cultured for 24,48 and 72 hours were significantly lower than those in the control cells (0.305 ±0.018 vs 0.354 ±0.011,t =5.24,P＜0.01;0.461 ±0.044 vs 0.551 ±0.027,t =3.91,P ＜0.01;0.74 ± 0.029 vs 0.881 ± 0.028,t =7.70,P ＜ 0.01).The relative migration rate of shLMTK3 cells 24 hours after scratching was significantly lower than that of control cells (0.51 ±0.096 vs 1.00 ± 0.029,t =4.81,P ＜ 0.01).Transwell assay showed that the number of migration cells in shLMTK3 group was significantly less than that in Scramble group (161 ±9.29 vs 308.66 ± 17.60,t =7.42,P ＜ 0.05).The results of flow cytometry showed that shLMTK3 cells were blocked at G1 phase (t =4.35,P ＜ 0.05),and that the inhibition of LMTK3 had no influence on the apoptosis of A549 cells.Conclusion Down-regulation of LMTK3 expression in human lung cancer A549 cells may inhibit the proliferation and migration of A549 cells significantly,indicating that the abnormal expression of LMTK3 in lung carcinoma cells may regulate the biological behaviors and progression of tumors.