PCGF1 is a prognostic biomarker and correlates with tumor immunity in gliomas

Polycomb group factor 1 (PCGF1) plays a vital role in the self-renewal of cancer stem cells (CSCs). However, the prognostic value and potential function of PCGF1 in glioma progression, especially in tumor immunity, remain unclear.

This study investigated PCGF1 expression in pan-cancers and glioma using The Cancer Genome Atlas Project data, and conducted a logistic regression analysis to analyze the association between PCGF1 expression and the clinicopathological features of glioma patients. Kaplan-Meier and Cox regression analyses were used to assess the prognostic roles of PCGF1. The functional analysis using gene ontology and Kyoto Encyclopedia of Genes and Genomes databases and a gene set enrichment analysis (GSEA) were conducted to examine the PCGF1-related biological processes and signaling pathways. Finally, the roles of PCGF1 in immune infiltration were analyzed by a single sample GSEA (ssGSEA).

PCGF1 expression was upregulated in glioma tissues. The high expression of PCGF1 was significantly associated with an age >60 years (P<0.001), an increased World Health Organization grade (P<0.001), and wildtype isocitrate dehydrogenase (IDH) status (P<0.001), and predicted poor overall survival (OS) [hazards ratio (HR) =2.90, 95% confidence interval (CI): 2.25-3.74; P<0.001], the progression-free interval (PFI) (HR =1.99, 95% CI: 1.60-2.46; P<0.001), and disease specific survival (DSS) (HR =2.84, 95% CI: 2.18-3.71; P<0.001). The multivariate regression analysis confirmed that PCGF1 expression was an independent prognostic factor of OS (HR =1.581, 95% CI: 1.161-2.153; P=0.004). Based on the functional enrichment analysis, we identified the PCGF1-related differentially expressed genes (DEGs), and found that PCGF1 was involved in regulating many oncogenic signaling pathways, such as the phosphatidylinositol 3-kinase and protein kinase B pathway, the Janus kinase/signal transducers and activators of transcription (JKT-STAT) signaling pathway, notch signaling and integrin signaling pathway. In addition, we found that PCGF1 expression was positively associated with the abundance of Th2, but negatively associated with T follicular helper, T central memory, and T gamma delta cells. Additionally, PCGF1 participated in the regulation of numerous immune-related processes in glioma.

PCGF1 is a promising prognostic biomarker, and as it governs cancer-related pathways and tumor immunity, it plays an important role in glioma development.