The Correlation Between CEL Expression And The Prognosis Of Survival In Breast Cancer Patients

ObjectiveThe enzyme carboxyl ester lipase(CEL),known as bile salt-dependent lipase(BSDL)or bile salt-stimulated lipase(BSSL),is mainly expressed in pancreatic acinar cells and lactating mammary glands.To investigate the link between CEL expression of breast cancer tissues and the survival of breast cancer patients by analyzing The Cancer Genome Atlas Breast Carcinoma(TCGA-BRCA)level 3 data.And the expression of CEL in breast cancer cells was preliminarily verified through experimental studies.MethodsThe clinical information and RNA-sequencing(RNA-Seq)expression data were downloaded from TCGA.Patients were divided into a high CEL expression group and a low CEL expression group using the optimal cutoff value(5.611)identified from the ROC curve.Chi-square test and Fisher exact test were used to find the correlation between the expression of CEL and clinicopathologic features.To assess the diagnostic capability,the receiver operating characteristic(ROC)curve of CEL was drawn.The survival differences between high and low CEL expression groups were compared by Cox regression analysis.Log-rank test was applied to the calculation of P values and the comparison of the Kaplan-Meier curves.Gene Set Enrichment Analysis(GSEA)was used to predict the regulatory genes of CEL.Furthermore,Gene Expression Omnibus(GEO)datasets were used for external data validation.RT-qPCR was used to detect the CEL expression in breast cancer cell lines(MDA-MB-231,SK-BR-3)and normal breast epithelial cells(MCF-10A).ResultsAnalysis of 1104 cases of tumor data showed that CEL was over-expressed in breast cancer.There were relationships between high CEL expression and clinicopathologic features.The high CEL expression group had a lower survival.By analyzing the area under the ROC curve(AUC)of CEL,it was found to have a limited diagnostic capability.CEL expression may be an independent prognostic factor for breast cancer survival through the multivariate analysis.The results of GSEA showed that the high CEL expression samples enriched epithelial mesenchymal transition,inflammatory response,TNF signaling pathway,estrogen response,coagulation and angiogenesis.The validation in GEO datasets also showed that CEL expression was higher in breast tumor tissues than in normal breast tissues.High CEL expression was associated with the poor overall survival of breast cancer.In addition,the results of RT-qPCR showed that the expression of CEL in breast cancer cell lines was significantly higher than that in normal breast epithelial cells.ConclusionThe expression of CEL in breast cancer is higher than that in normal breast,which may be an independent prognostic factor for the poor survival of breast cancer.