Hypoxia-induced lncRNA PDIA3P1 promotes mesenchymal transition via sponging of miR-124-3p in glioma.

Hypoxia is a critical factor in the malignant progression of glioma, especially for the highly-invasive mesenchymal (MES) subtype. But the detailed mechanisms in hypoxia-induced glioma MES transition remain elusive. Pseudogenes, once considered to be non-functional relics of evolution, are emerging as a critical factor in human tumorigenesis and progression. Here, we investigated the clinical significance, biological function, and mechanisms of protein disulfide isomerase family A member 3 pseudogene 1 (PDIA3P1) in hypoxia-induced glioma MES transition. In this study, we found that PDIA3P1 expression was closely related to tumor degree, transcriptome subtype, and prognosis in glioma patients. Enrichment analysis found that high PDIA3P1 expression was associated with epithelial-mesenchymal transition, extracellular matrix (ECM) disassembly, and angiogenesis. In vitro study revealed that overexpression of PDIA3P1 enhanced the migration and invasion capacity of glioma cells, while knockdown of PDIA3P1 induced the opposite effect. Further studies revealed that PDIA3P1 functions as a ceRNA, sponging miR-124-3p to modulate RELA expression and activate the downstream NF-κB pathway, thus promoting the MES transition of glioma cells. In addition, Hypoxia Inducible Factor 1 was confirmed to directly bind to the PDIA3P1 promotor region and activate its transcription. In conclusion, PDIA3P1 is a crucial link between hypoxia and glioma MES transition through the PDIA3P1-miR-124-3p-RELA axis, which may serve as a prognostic indicator and potential therapeutic target for glioma treatment.