Cathepsin Ⅴ In Prognosis,the Tumor Microenvironment And Treatment Of Lung Adenocarcinoma Based On Bioinformatics

Objective:Based on the high incidence rate and strong ability of proliferation and malignant invasion of lung adenocarcinoma(LUAD),it accounts for a high proportion of malignant tumor related deaths in China and even the world.Although some patients with lung adenocarcinoma have achieved clinical benefits after surgical treatment,chemotherapy,radiotherapy,targeted treatment and immunotherapy,there are still a large number of patients with lung adenocarcinoma who are unable to inhibit tumor progression or treatment side effects to end up dying due to improper choice of treatment methods or clinical lack of matching treatment methods.It can be seen that it is of convincing practical significance to find an index that can be used for prognosis evaluation and treatment selection of lung adenocarcinoma patients.Cathepsin V(CTSV),a member of the cysteine cathepsin family,is a powerful protease.In previous studies,it has been reported that the CTSV expression has a good predictive effect on the prognosis of lung adenocarcinoma patients,but its predictive value has not been systematically reviewed,and its research on tumor microenvironment(TME),immunotherapy and anti-tumor drug sensitivity in lung adenocarcinoma patients has not been involved in other literature.The purpose of this study was to explore the value of CTSVexpression in the prognosis,TME and treatment of lung adenocarcinoma patients.Methods:The expression of m RNA and mi RNA in tumor tissues and adjacent tissues of lung adenocarcinoma patients,as well as the survival information and clinicopathological characteristics of corresponding patients were obtained from TCGA database and GEO database.Using GEPIA database and R software to analyze the difference of CTSV expression in tumor samples and adjacent samples.Then R software was used to divide the lung adenocarcinoma tissue in TCGAdatabase into high and low groups by the median value of CTSV expression,and the function and pathway of the differentially expressed genes in the two groups were enriched and analyzed.The expression of CTSV and the total survival rate(OR)of lung adenocarcinoma samples from TCGA,GSE3775,GSE50081 and GSE72094 were analyzed by using R software with Km method and cox method respectively.ROC curve and consistency index(C-index,consistency index)were used to evaluate the predictive effect of CTSV expression on lung adenocarcinoma patients.Multivariate cox regression analysis was used to evaluate the impact of clinicopathological characteristics and the expression of CTSVon prognosis,and a nomogram was established to help the index apply to clinical practice.The relationship between the CTSV expression and TME was explored by calculating the immune score,matrix score and the degree of infiltration of multiple immune cells in patients with lung adenocarcinoma by using the ESTIMATE and CIBERSORT methods.The TIMER database was used to plumb the correlation between the degree of immune cell infiltration in LUAD tumor microenvironment and the expression of CTSV.Pearson correlation analysis of CTSV expression and immune checkpoint gene was performed in TCGA lung adenocarcinoma gene expression matrix.TCGA lung adenocarcinoma samples were scored with the TCIAdatabase related to immunotherapy,and the Pearson correlation analysis of scores were analyzed in the high and low CTSVexpression groups.The sensitivity data of 385 drugs in GDSC2 and "p RRorphic" package were extracted from TCGAlung adenocarcinoma samples with R software,and Pearson correlation analysis was performed between CTSV expression and half maximal inhibitory concentration(IC50)of drugs.The starebase database was used to screen the mi RNAs with binding sites with CTSV,and the Pearson correlation analysis of these mi RNAs with the expression of CTSV was performed in TCGA lung adenocarcinoma samples.The mi RNAs negatively related to the expression of CTSV were screened for differential analysis and survival analysis of lung adenocarcinoma and adjacent tissues,and the mi RNAs that antagonize CTSV expression and are related to prognosis were identified.Double luciferase assay was used to verify whether the identified mi RNAcould target CTSV.Results:The CTSV expression can better identify lung adenocarcinoma tissue and normal tissue.The results of gene function enrichment analysis showed that it was mainly enriched in chromosomes,nuclei and proteases.The results of gene pathway enrichment analysis included cell cycle,DNA replication,DNA repair,cell division,immune regulation and proteasome.The meta-regression analysis of CTSV expression and OS selection common effect model of lung adenocarcinoma samples from TCGA,GSE3775,GSE50081 and GSE72094 showed that the comprehensive HR value(risk ratio)>1.95% CI=1.17-1.47,.P <0.00001.It was determined that the high expression of CTSV was a risk factor for lung adenocarcinoma death.Multivariate cox regression analysis confirmed that CTSV expression can act as an independent risk factor for survival.The immune infiltration analysis showed that the immune score and stromal score of the high expression CTSV group were low,and the immune cells that promote immune escape,such as bone marrow-derived suppressive cells(MDSCs),resting natural killer cells(NKs),cancer associated fibroblasts(CAFs),were positively correlated with the CTSV expression,while the dendritic cells(DCs)that present tumor antigen and activated NKs that play an important role in killing tumor were negatively correlated with the CTSV expression.In particular,MDSCs were positively correlated with the expression of CTSV in most cancers(24/32),and the prognosis of the high CTSV expression group in the high MDSCs infiltration group was significantly worse than that of the group with the low CTSV expression group.The expression of CTSV was negatively correlated with the expression of most immune checkpoint genes.In addition,anti-PD-1 and anti-CTLA4 treatment response scores were negatively correlated with CTSVexpression.The results of drug sensitivity analysis showed that the high expression of CTSV suggested that the IC50 values of chemotherapeutic drugs acting on DNA replication,mitosis and cell cycle were lower,such as cisplatin,pentafluorouracil,paclitaxel,vinblastine,and gemcitabine,and the IC50 values of targeted drugs acting on RTK and EGFR signal pathways were lower,such as lapatinib,gefitinib,and dasatinib.The low expression of CTSV suggests that the IC50 value of the related drugs acting on the kinase is lower.Correlation analysis and target prediction of mi RNA database obtained two mi RNAs that may down-regulate CTSV and differentiate adenocarcinoma tissue and prognosis,namely hsa-mi R-133a-3p and hsa-mi R-133 b.In addition,dual-fluciferase detection confirmed that hsa-mi R-133a-3p can target CTSV3’UTR.Conclusion:For patients with lung adenocarcinoma,the high expression of CTSV predicts a worse prognosis.The low CTSV expression indicates that anti-tumor immune infiltration(DCs,activated NKs)is more active,while the high CTSV expression indicates that inhibitory immune cell infiltration(MDSCs,resting NKs,CAFs)is more significant,suggesting that TME plays a part in leading the worse prognosis of lung adenocarcinoma patients with high CTSV expression.MDSCs are positively correlated with CTSV expression in most cancers(24 out of 32 cancers),and the prognosis of lung adenocarcinoma patients in the high CTSV expression group in the high MDSCs infiltration group is significantly worse than that in the low CTSV expression group.Combined with previous studies,it can be speculated that MDSCs may promote the progression of lung adenocarcinoma by promoting the expression of CTSV.CTSV may play an important role in cell cycle,DNAreplication,mitosis,RTK and EGFR signal pathways.The drug sensitivity of common lung adenocarcinoma drugs acting on these sites can be predicted by detecting the expression of CTSV,such as cisplatin,paclitaxel,gemcitabine,lapatinib,gefitinib,and dasatinib,so as to optimize the clinical treatment options.Hsa-mi R-133a-3p is an upstream regulator of CTSV,which can inhibit its expression.Its high expression suggests that patients with lung adenocarcinoma have better prognosis.In conclusion,CTSV has great value in the prognosis,TME and treatment of lung adenocarcinoma patients.