Proteomics Analysis Of Plasma Membrane Of Nasopharyngeal Carcinoma Cell Line

Cell surface proteome expressing in nasopharyngeal carcinoma cell line was analysised using three methods: (1)Extract peripheral membrane proteins were enriched by 0. 1M Na₂C0₃.,H₂0 and biotinylate;(2)Total plasma membrane fractions were enciched by 30% Percoll density grade centrifugation;(3) Integral plasma membrane fractions were obtained by treating the post-nuclear supernatant with 0. 1M Na₂C0₃ followed by 30% Percoll density grade centrifugation. All the proteins collected were then separated and identified by SDS-PAGE-ESI-Q-TOF, 2DE-MALDI-TOF-TOF and "shotgun". In our studies, 856 non- redundant proteins were identified. These proteins were submitted to bioinformatics analysis, it was found that among them, 58 proteins were cancer related proteins, 112 proteins played potential roles in a wide of cell signal conduction, and 21 proteins were found in 6 disease pathways. Furthermore, we also submitted the proteins to Binding database, and construct a protein-protein interaction network by using Pajek analysis. Besides, We carried out an immunocytochemistry analysis of Galectin-1, nm23, Keratin 8, HSP-70, VCP which were annoted to be located in cytosol or nuclear. The result positively indicated that they were also widely distributed in plasma membrane.Meanwhile, the other project we focused on was differential expression of plasma membrane proteome of CNEI&CNE2,two Nasopharyngeal carcinoma cell lines with different differentiation level. Plasma membrane proteins were enriched and separated with 2DE。By PD Quest 7.2 analysis, 13 proteins were found to be different expressed and identified by MALDI-TOF-TOF. Some proteins of interest were confirmed by Western Blot analysis, and Real-time PeR was applied to analysis different expression of mRNA.