DIAPH3 AND CKAP2L IN GLIOMA GENESIS AND PROGRESSION: INSIGHTS FROM TRANSCRIPTOMIC PROFILING AND FUNCTIONAL ANALYSES

Abstract

Neural stem cells undergo rapid and continuous cycling that make them prone to mitotic errors and predispose them to neoplastic transformation. DIAPH3 deficiency is known to induce aberrant mitosis, chromosomal instability, and loss of neural progenitors. Low expression of DIAPH3 is also linked to poor prognosis in glioblastoma patients. To investigate the role of DIAPH3 in gliomagenesis, we used a Trp53/Diaph3 conditional knockout mouse model and performed transcriptomic profiling on early and advanced tumors collected from the same animals. RNA-sequencing was used to identify molecular changes underlying GBM progression and to select candidate genes for further analysis. Functional assays were then conducted in U251-MG glioblastoma cells to evaluate the roles of these candidate genes in tumor-related processes. Combined loss of Trp53 and Diaph3 promoted high-grade diffuse glioma and accelerated tumor onset in mouse model. Transcriptomic analyses revealed apparent stage-dependent alterations as the tumor progressed, including reduced neural activity and changes in genes involved in extracellular matrix (ECM) interactions. Using an siRNA screen of gene candidates from RNA-seq results, CKAP2L emerged as a top hit and experimental assays showed that CKAP2L depletion reduced proliferation, migration and induced G2M accumulation. We also used TCGA data to identify a differentially methylated CpG site at the CKAP2L promoter which is linked to corresponding changes in gene expression in glioma datasets, where high-grade tumors show hypomethylation and higher CKAP2L expression. CKAP2L expression correlates with stemness and proliferative markers pointing to a potential role in maintaining stem-like tumor cell behaviour. Overall, our findings show that CKAP2L contributes to glioma progression, may help distinguish tumor grade, and represents a potential therapeutic target in glioblastoma.

Date of Award	2026
Original language	American English
Awarding Institution	HBKU College of Health & Life Sciences