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Figure 1. PDIA4 is highly expressed in gliomas and significantly associated with tumor aggressiveness.
  1. Differential expression of LCTL in brain lower grade glioma (LGG) and glioblastoma (GBM) compared to levels in normal brain tissues.
  2. The relative mRNA expression level of PDIA4 in the normal glial cell line HEB and glioma cell lines.
  3. The PDIA4 expression in glioma of WHO grade Ⅱ-Ⅳ based on both TCGA and CGGA datasets.
  4. The expression of PDIA4 in IDH subtypes of gliomas based on both the TCGA and CGGA datasets.
  5. PDIA4 expression pattern in different molecular subtypes of glioma (classical, mesenchymal, neural, proneural) in the TCGA dataset.
Figure 2. PDIA4 is a prognostic factor for glioma patients.
(A-B) Kaplan–Meier survival analysis showing that high PDIA4 expression predicts poor prognosis for glioma patients based on both the TCGA and CGGA datasets.
(C-D) Kaplan–Meier survival analysis showing that high PDIA4 expression predicts poor prognosis for glioblastoma multiform (GBM) patients in both the TCGA and CGGA datasets.
(E-F) Kaplan–Meier survival analysis showing that high PDIA4 expression predicts poor prognosis for lower grade glioma (LGG) patients in both the TCGA and CGGA datasets.
Figure 3. Functional enrichment analysis of PDIA4 in TCGA and CGGA cohorts
(A-B) The top10 biological process terms of GO enrichment analysis based on TCGA and CGGA datasets respectively.
(C-D) The top10 molecular function terms of GO enrichment analysis based on TCGA and CGGA datasets respectively.
(E-F) The top10 cellular component terms of GO enrichment analysis based on TCGA and CGGA datasets respectively.
(G-H) KEGG pathway analysis based on TCGA and CGGA datasets and the top 10 terms were visualized respectively.
Figure 4. PDIA4 correlated with ESTIMATE algorithm/xcells scores in glioma and the PPI network
(A) PDIA4 expression was positively correlated with immune score and stromal score in glioblastoma multiform (GBM) patients.
(B) PDIA4 expression was positively correlated with immune score and stromal score in lower grade glioma (LGG) patients.
(C) PDIA4 expression was significantly correlated with 46 cell types, as calculated by xcells in glioma.
(D) Protein-protein interaction (PPI) network of PDIA4.
Table 1 Univariate and multivariate analysis based on the TCGA Dataset.