Screening Of Cervical Cancer Prognosis-Related Molecule CD79B And Studying On Its Expression And Clinical Significance

Objective:Cervical cancer(CC)is a common gynecological malignancy and one of the leading causes of cancer deaths in women.At present,there are many clinical treatment methods for cervical cancer,but the prognosis of cervical cancer patients still needs to be improved.At the same time,existing studies have shown that the tumor microenvironment can affect the prognosis of cancer.Therefore,in this study,we aimed to find prognosis-related biomarkers in cervical cancer from the tumor microenvironment to predict the prognosis or immunotherapy response of cervical cancer patients.Method:We used ESTIMATE and CIBERSORT algorithms to calculate the quantity of immune and stromal components and the abundance of tumor-infiltrating immune cells in309 cervical samples from The Cancer Genome Atlas(TCGA)database.Immune-specific differentially expressed genes(DEGs)associated with cervical cancer patients’prognosis were screened by the intersection of multivariate Cox regression analysis and PPI network.Further,we included these immune-specific DEGs in a random forest regression model,identified CD79B as the core gene,and performed a series of analyses,including differential expression analysis,survival analysis,clinical correlation analysis,gene set enrichment analysis(GSEA),and correlation analysis with infiltrating immune cells and immunoregulatory genes.In the differential expression analysis of CD79B,we collected 30fresh cervical tissue specimens from the local hospital for RT-qPCR experiments to validate the mRNA level of CD79B,and collected 74 clinical cervical tissue paraffin specimens for immunohistochemistry experiments to validate the protein localization and expression level of CD79B.In the survival analysis,we followed up the survival data of 42 cervical cancer patients and combined with CD79B immunohistochemistry score to validate the survival analysis result of CD79B in the TCGA database.Additionally,we also evaluated the prognostic value of CD79B-associated immunoregulatory genes by univariate and multivariate Cox regression analysis and constructed an immune-specific prognostic risk model.Then,we further verified the efficacy of the risk model as an independent prognostic factor for cervical cancer patients via Kaplan-Meier survival analysis,ROC curve,and Cox regression analysis.Finally,based on the risk score of the prognostic model and important clinical variables,we constructed and evaluated a nomogram for visually predicting the 3-year and 5-year overall survival of cervical cancer patients.Result:1.A total of 425 genes(up-regulated gene:408;down-regulated gene:17)were identified as immune-specific differentially expressed genes in cervical cancer based on Immune Score and Stromal Score.Meanwhile,CD79B was the most important feature gene in the random forest regression model;therefore,we screened CD79B as the core gene for further study.2.Differential expression analysis:compared with normal cervical tissues,the results from GEPIA2 database and RT-qPCR experiments showed that the mRNA expression level of CD79B was down-regulated in cervical cancer,while the results from the HPA database and immunohistochemistry experiments revealed that the protein level of CD79B was up-regulated in cervical cancer.3.Clinical correlation analysis:the results from TCGA-CESC dataset showed that the high expression level of CD79B was significantly correlated with patient’s race,primary therapy outcome,tumor histological type and degree of pathological differentiation(p<0.05),whereas there was no correlation between high CD79B expression and patients’age,tumor clinical stage,histological grade,radiotherapy and body mass index(p>0.05).4.Survival analysis:the survival curve from the TCGA-CESC dataset and the result of 42 cervical cancer patients with clinical follow-up in local hospital both showed that high expression of CD79B was associated with a good prognosis in cervical cancer patients(p<0.05),and CD79B may be a new prognostic indicator for cervical cancer.5.GSEA analysis:the functions and signaling pathways participated by CD79B were mainly related to immune activities,such as adaptive immune response based on somatic recombination of immune receptors built from immunoglobulin superfamily domains,B cell activation,cell recognition,humoral immune responses,antigen processing and presentation,and B cell receptor signaling pathway.6.The correlation analysis of CD79B with immune cells showed that the expression of CD79B was different in 10 kinds of tumor-infiltrating immune cells.At the same time,the infiltration number of CD79B was positively correlated with the infiltration number of naive B cells,plasma cells,CD8~+T cells,regulatory T cells,and M1 macrophages,while it was negatively correlated with the infiltration number of activated NK cells,M0macrophages,activated dendritic cells,activated mast cells,and eosinophils.7.Based on the CD79B-associated immunomodulators,the 10-gene(CD96,LAG3,PDCD1,TIGIT,CD27,KLRK1,LTA,PVR,TNFRSF13C,TNFRSF17)immune-specific prognostic model established by us has good independent prognostic value for cervical cancer patients(p=1.526e-06;AUC=0.864),and the nomogram constructed by integrating clinical variables and this immune-specific prognostic model’s risk score could be personalized to predict the3-year and 5-year overall survival rate of cervical cancer patients(C-index=0.83).Conclusion:1.CD79B is a new biomarker for good prognosis of cervical cancer.2.The expression level of CD79B is correlated with the infiltration abundance of immune cells such as B lymphocytes and CD8~+T lymphocytes,suggesting that CD79B may play an important role in regulating the immune microenvironment of cervical cancer and is expected to become a potential immune therapeutic target for cervical cancer.3.The10-gene prognostic model constructed based on CD79B-related immunomodulators has good predictive efficacy in predicting the overall survival of cervical cancer patients.