Screening Of Downstream Target Protein After CacyBP/SIP Nuclear Translocation In Colon Cancer Cells

Objective: Colon cancer is one of the most common gastrointestinal cancer with increasing incidence and mortality rates,which seriously endangers people’s health has become a major problem in the world.However, the underlying mechanism is still unclear.Cacy BP/SIP(Calcyclin-binding protein, Cacy BP/SIP) mainly expressed in the cytoplasm. Our study showed that gastrin can stimulate Cacy BP/SIP nuclear translocation in colon cancer cells and promot colon cancer cells proliferation. In the present study, we prepare to screening of the target proteins after Cacy BP/SIP nuclear translocation, exploring signaling pathways and reveal the possible mechanism of colon cancer.Methods: The cell models of Cacy BP/SIP nuclear translocation were constructed. The subcellular location of Cacy BP/SIP in colon cancer cells induced by gastrin was observed by immuneofluorescence and Western Blot.We used a quantitative proteomic approach with isobaric labeling(i TRAQ) to examine changes in the plasma proteome of colon cancer cells before and after gastrin stimulation. The identified proteins were further analyzed by bioinformatic software GO and KEGG pathway analysis.Results: In unstimulated cells, Cacy BP/SIP was distributed throughout the cytoplasm and Cacy BP/SIP could translocate to the perinuclear region upon stimulation of gastrin. These phenomena were also observed with Western Blot. Two biological replicates of i TRAQ analyses were carried out. 2193 proteins were found in the i TRAQ analysis, 173 upregulated proteins and 132 downregulated proteins were identified. Proteins of intersection were analyzed by informatics.The binding function and catalytic activity function were the main molecular ftmction; biological processes mainly include biosynthetic process, cellular process; the main cellular component is organelle.There are 7 proteins which Located in the nucleus and had the function of binding, PML、VDAC2、Annexin A1、UBE2、Filamin-A, Heat shock protein beta-1、Cathepsin B. In this study, all identified proteins(305) belong to 67 signaling pathways with KEGG analysis, but only 6 signaling pathways were the significant(p<0.05), the proteins expressed in the four pathways, including:Calcium signaling pathway 、Ubiquitin mediated proteolysis、VEGF signaling pathway、MAPK signaling pathway.Conclusion: 2193 proteins were found in the i TRAQ analysis, 173 up regulated proteins and 132 down regulated proteins were identified. The main biological processes is biosynthetic process and main molecular functions is binding. All identified proteins belong to 67 signaling pathways with KEGG analysis, 6 signaling pathways were the significant(p<0.05), the proteins expressed in the four pathways,...