Prognosis And Immune Infiltration Analysis Of Phospholipid Metabolism-related Gene PLBD1 In Glioma

Objective: Glioma accounts for the largest proportion of primary malignancies in the central nervous system,the most common and malignant of which is glioblastoma.The therapeutic value of classical treatment strategies for glioma is effective but also limited.In a variety of solid tumors,the therapeutic value of immunotherapy brings new opportunities for the treatment of glioma.Exploring prognostic features and potential mechanisms associated with immune infiltration of glioma is important for effectively predicting patient prognosis and formulating treatment options.Phospholipid metabolism is significantly altered in certain gliomas and is involved in regulating behaviors such as tumor cell proliferation in glioma.Phospholipid metabolism remodeling can also affect the tumor immune response in glioblastoma.Therefore,a systematic and comprehensive correlation analysis of phospholipid metabolism-related genes with the prognosis and immune infiltration of glioma is necessary.Methods: In this study,three R packages(DESeq2,edge R,and limma)were first used to perform differential expression analysis on the data from the UCSC Xena website to evaluate the expression differences of phospholipid metabolismrelated genes between glioma and normal samples,and thirty-two differentially expressed genes related to phospholipid metabolism were screened.Based on the data of the Chinese Glioma Genome Atlas(CGGA),univariate Cox regression analysis was used to further select seventeen glioma prognosis-related genes,including PLBD1(Phospholipase B domain-containing protein 1).These members were used to calculate sample risk score(Riskscore)in CGGA and The Cancer Genome Atlas(TCGA)glioma cohorts.After fully evaluating the prognostic value of phospholipid metabolismrelated genes,PLBD1 was selected as the target gene for further study,and pancancer analysis was performed through the UCSC Xena-Shiny website to evaluate its research value.Multiple public databases were used to assess the expression level of PLBD1 in glioma and to find associations between PLBD1 and the clinical and molecular characteristics of glioma.Kaplan-Meier plot,univariate Cox regression analysis,and multivariate Cox regression analysis were used to analyze whether PLBD1 expression correlated with the prognosis of glioma patients.The “rms” R package was used to construct a clinical prediction model(nomogram)based on PLBD1 expression,and the accuracy of the prediction model was evaluated using Concordance-Index and Calibration Curve.Copy Number Variation(CNV)and somatic mutation data for each grade of glioma samples were obtained from TCGA.The Gene Pattern website was used for online analysis of copy number variation data.The “GSVA” R package,the TIMER website,and the TISIDB website were used to analyze the correlation between PLBD1 and immune infiltration of glioma.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses were performed with the “cluster Profiler” R package and GSEA software to identify potential pathways in which PLBD1 may play a role in glioma.In this study,R and RStudio software were used for data collation,analysis,and visualization.Results: The expression levels of thirty-two phospholipid metabolismrelated genes in glioma samples were different from normal brain tissue.Seventeen genes,including PLBD1,were associated with the prognosis of glioma patients.Riskscore constructed based on the seventeen phospholipid metabolism-related genes was also related to the prognosis of glioma patients.Compared to non-neoplastic brain tissue,the expression level of the target gene PLBD1 was upregulated in glioma and was correlated with clinical and molecular characteristics of glioma.Data analysis suggested that PLBD1 was associated with certain genomic alterations in glioma.PLBD1 was correlated with clinical outcomes in patients with glioma and had value as an independent prognostic factor for glioma.The clinical prediction model constructed based on PLBD1 expression had good accuracy after evaluation by Concordance-Index and Calibration Curve.Various evidence suggested that PLBD1 was related to immune infiltration of glioma,and was significantly associated with many immune-related molecules and immune-prognostic markers.Functional enrichment analysis also suggested that PLBD1 may affect the biological behaviors of glioma such as cell adhesion and apoptosis.Conclusion:1 The expression of phospholipid metabolism-related gene PLBD1 is upregulated in glioma and may indicate a poor prognosis for glioma.2 The clinical prediction model constructed based on PLBD1 expression has good accuracy.3 PLBD1 may be associated with immune infiltration of glioma.4 PLBD1 may be involved in regulating biological behaviors such as cell adhesion and apoptosis in glioma.