| Objective: This study aimed to elucidate potential clinical and biological function of CX3CL1 mRNA expression in Non-small cell lung cancer.Methods: By retrieving lung cancer related data in NCBI GEO database and TCGA of UCSC Cancer Browser,we retrieved 8 relevant datasets based on inclusion and exclusion criteria.Downloaded data was read in,processed and standardized in R language.Cutoff point of CX3CL1 mRNA expression level was determined according to Cutoff Finder(http://molpath.charite.de/cutoff/).Univariate and multivariate Cox models were fitted in each dataset.CX3CL1 associated HR value was calculated,then HR values of all datasets were summarized by meta algorithm,and finally the prognostic value of CX3CL1 mRNA was determined.The correlation coefficients of CX3CL1 with all other genes in each dataset were calculated,and enrichment analysis was performed for the gene with the highest correlation coefficient.Results: High-expression of CX3CL1 mRNA in tumor tissues of lung adenocarcinoma(LUAD)was a positive prognostic factor for overall survival(OS)(pooled hazard ratio(HR)= 0.53;95% confidence interval(CI)= 0.43-0.65;P<0.001 in univariate analysis;pooled HR = 0.52;95% CI = 0.42-0.64;P<0.001 in multivariate analysis).But in lung squamous cell carcinoma(LUSC),There was no significant association between CX3CL1 expression and prognosis(HR = 1.09;95% CI= 0.82-1.45;P = 0.536 in univariate analysis;pooled HR = 1.18;95% CI = 0.88-1.58;P = 0.282 in multivariate analysis).Furthermore,the genes highly correlated with CX3CL1 were performed with enrichment analysis and the results in lung adenocarcinoma showed that the most significant biological processes were signal transduction(GO:0007165),T cell costimulation(GO:0031295),leukocyte migration(GO:0050900)and so on,and the most important pathways asssociated with tumor immunity were as follows,Cell adhesion molecules(KEGG: hsa04514),Leukocyte transendothelial migration(KEGG: hsa04670),Naturalkiller cell mediated cytotoxicity(KEGG: hsa04650)and so on.But in the patients with LUSC,the CX3CL1 highly correlated genes didn’t enriched to any biological process and signal pathways.Conclusion: mRNA level of CX3CL1 in lung adenocarcinoma was positively associated with better prognosis,but there was no correlation between CX3CL1 mRNA level and prognosis in lung squamous cell carcinoma patients.CX3CL1 may be used as a potential prognostic marker for lung adenocarcinoma patients. |
