Objective To investigate the effect and potential molecular mechanism of PTGS2 on the prognosis of colon cancer patients.Methods The transcriptomic and proteomic data of pan-cancer were collected from TCGA,HPA,UALCAN and other databases,and the expression pattern and prognostic value of PTGS2 were analyzed by combining the clinical data such as staging,histology,survival time and so on.Based on GSEA,the biological functions which were significantly activated in patients with high expression of PTGS2 were iden-tified and the colon cancer cell line SW480 was used as an example for in vitro validation.PTGS2 over-expressing cell strains were constructed,and the effect on cell proliferation was determined by CCK8 method.Different concen-trations of H2O2 were used to form gradient oxidative stress,and the changes in cell antioxidant capacity were detected.The regulatory mechanism was preliminarily verified by Western blot.Results The transcription and expression of PTGS2 were found to be significantly up-regulated in colon cancer patients(P<0.05),and the increased expression of PTGS2 was associated with an increased mortality risk(P<0.05).Data analysis and in vitro experiments showed that over-expression of PTGS2 may promote the proliferation of colon cancer cells by activating the mTOR pathway.The antioxidant effect of cells was regulated by up-regulating oxidative stress regulatory proteins SOD2 and NRF2.Conclusions PTGS2 is a potential risk factor for colon cancer and its over-expression promotes cell proliferation,enhances cell antioxidant effect and is associated with poor progno-sis of colon cancer patients.

After decades of development,protein and peptide drugs have now grown into a major drug class in the marketplace.Target identification and validation are crucial for the discovery of protein and peptide drugs,and bioinformatics prediction of targets based on the characteristics of known target proteins will help improve the efficiency and success rate of target selection.However,owing to the developmental history in the pharmaceutical industry,previous systematic exploration of the target spaces has mainly focused on traditional small-molecule drugs,while studies related to protein and peptide drugs are lacking.Here,we systematically explore the target spaces in the human genome specifically for protein and peptide drugs.Compared with other proteins,both suc-cessful protein and peptide drug targets have many special characteristics,and are also significantly different from those of small-molecule drugs in many aspects.Based on these features,we develop separate effective genome-wide target prediction models for protein and peptide drugs.Finally,a user-friendly web server,Predictor Of Protein and Peptide drugs'therapeutic Targets(POPPIT)(http://poppit.ncpsb.org.cn/),is established,which provides not only target prediction specifically for protein and peptide drugs but also abundant annotations for predicted targets.