A Preliminary Application Of Quantitative Proteomic Technique In NSCLC Metastasis-associated Mechanism

Lung cancer is the malignant tumor leading to highest cancer-related morbidity and mortality in the world,about 85%of lung cancers are non-small cell lung cancers(NSCLC).Although great progresses about diagnosis and treatment for the disease have been made,the metastasis is still the vital reason which affected 5-year survival rate of lung cancer patients.But the pathogenesis of this deadly disease is still unclear,which needs to be clarified.Mass spectrometry technology,as an emerging and rapidly developed technology,provides a powerful means for cancer research.We used the 2D LC-MS/MS proteomics platform combined with SWATHTM(Sequential Windowed Acquisition of all theoretical fragment ions,SWATH TM)to analyze SPC-A-1 cells and SPC-A-lsci cells Using titanium dioxide enrichment,a total of 154 differentially expressed proteins were identified,of which 125 were up-regulated and 29 were down-regulated.By comparing with the protein information provided in the website Uniprot,two of the down-regulated phosphorylated proteins were not phosphorylated proteins,and the rest were phosphorylated proteins.These results indicated the preliminary establishment of the phosphorylation peptide enrichment method in our lab.We use SWATH TM quantification approach to analyze the nucleoproteins in two pairs of cells.SPC-A-lsci,H1299 are the lung cancer cell lines with high metastatic potential and SPC-A-1,H358 are the lung cancer cell lines with low metastatic potential.Results showed that 63 proteins were differentially expressed.The expressions of dysregulated proteins at the gene level were detected by real-time quantitative PCR.The results were consistent with those of mass spectrometry.FUBP2 was selected as the research target,and cell lines in which FUBP2 was stably knocked down were constructed.It was proved that FUBP2 may have an important role in the process of lung cancer metastasis in vivo and in vitroOur earlier study has shown that miR-148a suppressed the metastasis of NSCLC both in vitro and in vivo.However,the modulatory mechanism remains unclear.The isobaric tags for relative and absolute quantitation(iTRAQ)combined with nano liquid chromatography-tandem mass spectrometry(Nano-LC-MS/MS)were used to explore the molecular mechanism by which miR-148a suppressed the metastasis of NSCLC.A total of 84 differentially-expressed proteins were found.The combination of proceomics and bioinformatics analysis was a new idea to provid for the study of miR-148a inhibition of lung cancer metastasis.