Analysis Of The Expression And Clinical Significance Of TIGIT In Invasive Breast Cancer Based On TCGA Database

Objective: To assess the levels and potential therapeutic and prognostic significance of TIGIT in invasive breast cancer.Methods: The TCGA database was used to evaluate TIGIT levels in 1222 invasive breast cancer samples and its association with clinicopathological features.Immunohistochemistry was used to detect TIGIT protein levels in 12 invasive breast cancer and normal tissue samples collected in our hospital.Further,Kaplan-Meier survival curve,Cox regression model,ROC curve and nomogram were applied in analyzing the role of TIGIT in the diagnosis and prognosis of invasive breast cancer.The GO/KEGG and GSEA enrichment analyses techniques were used to investigate the possible cellular mechanism,and STRING database was used to explore TIGIT related proteins.Finally,the correlation between TIGIT and immune cell infiltration in invasive breast cancer was analyzed.Results: Relative to normal tissues,TIGIT levels in invasive breast cancer were elevated(P<0.001).TIGIT m RNA level was significantly different from T stage,age,ER and PR level(P<0.01).The high levels of TIGIT exhibited positive correlations with OS,PFI and RFS(P<0.05).Multivariate analysis showed that the expression level of TIGIT is an independent risk factor for predicting PFS;pathological staging is an independent risk factor for OS,DSS and PFS;M stage is an independent risk factor for DSS and PFS;Age,menopause and radiotherapy were independent risk factors for OS;N stage is an independent risk factor for predicting DSS.TIGIT has certain accuracy in the diagnosis of invasive breast cancer(AUC=0.809,CI:0.785～0.832).CD226,INPP5 D,PVR,PVRL2 and PVRL3 proteins interact with TIGIT.The expression level of TIGIT was positively correlated with the infiltration of immune cells(such as T cells,Cytotoxic cells,TReg,Th1 cells and a DC)(r>0.8,P<0.001).Conclusion: TIGIT is highly expressed in invasive breast cancer,suggesting a good prognosis of the patients.The expression of TIGIT is significantly correlated with the infiltration of immune cells in invasive breast cancer and may be a potential target for immunotherapy.