Effects of Si-10 on malignant proliferation of lung cancer cells with different COX-2 expression states in vitro

OBJECTIVE:To explore the effects of Si-10 on the lung cancer cells with different cyclooxygenase-2 (COX-2) expression states by using the same target to interfere in COX-2 gene expression and study the effect on the malignant proliferation of these cells in vitro.METHODS:The siRNA expression vector (psi-10) and the vacant vector (pEGFP) were transfected into these cells with different COX-2 expression states respectively and the transfected cell strains were constructed.The change of COX-2 expression levels was examined by Western blot and RT-PCR.The effects on the proliferation of lung cancer cells were studied by the cell growth curve and clonogenic assay.RESULTS:These cells transfected pEGFP had the expression of GFP and 801D-10,A549-10 and LTEP-A2-10 had not in 24,48 and 72 hours after transfected.The expression of COX-2 was inhibited in LTEP-A2 and A549 expressing COX-2 but the inhibited effects were different.The expression of COX-2 was inhibited more obviously in LTEP-A2 cells than in A549 cells.In contrast to their maternal lines,the levels of COX-2 mRNA of LTEP-A2-10 and A549-10 cells reduced by 64.2% and 61.2% respectively and these of COX-2 protein reduced by 60.2% and 56.2% respectively.The growth of LTEP-A2-10 and A549-10 cells slowed and the clonal formation rate reduced.The growth of 801D-10 cells had not obvious changes.CONCLUSION:The si10 has different interfering effects on lung cancer cells with different COX-2 expression states and the different interfering results have different effects on cell malignant proliferation.