Effects of metallothionein-3 expression on biological behaviors of A549 lung cancer cells

Abstract

Objective To study the efects of metallothionein-3 (MT-3) expression on biological behaviors of A549 lung cancer cells.Methods The anti-proliferation and the cytotoxicity of MT-3 on A549 cells were detected by methyl thiazol tetrazolium (MTT) assay.The MT-3 expression was observed in A549 cells,and the mRNA level was detected by reverse transcription-polymerase chain reaction (RT-PCR).The morphological changes of the apoptotic cells were observed by invert microscope,hematoxylin and eosin (HE) stain,transmission electron microscope and acridine orange/ethidium bromide (AO/EB) double fluorescent staining.The data were analyzed by using SPSS 14.0 statistical software.Results The MT-3 expression in A549 cells transfected with MT-3 gene was confirmed by RT-PCR and immunocytochemical method,respectively.Compared with the control group,-fos and c-jun mRNA levels were decreased significantly in PEFMT-3 transfected A549 cells (x2 =2.536,P ＜ 0.05).MTT assay revealed that the inhibitory rate was enhanced obviously with the increase of effect/target rate and extension of time (x2 =2.795,P ＜0.05).The apoptosis or necrosis of A549 cells was morphologically observed after lung cancer cells were induced by MT-3 for 24 h.Conclusion MT-3 could inhibitit proliferation of A549 cells and promote apoptosis of A549 cells probably by negatively regulating the signaling pathway to ruduce the expression of c-fos and c-jun. Key words: Lung cancer; Metallothionein-3; Apoptosis