Background and objectives: Cancer stem cells (CSCs) may contribute to tumor initiation, distant metastasis, and chemo-resistance. Quaking (QKI) is a RNA binding protein, a tumor suppressor, and a well-known stem cell biomarker in central nervous system (CNS) cancer. The aim of this study was to identify the potential of QKI mRNA as a prognostic marker for CNS cancer.
Methods: The Cancer Genome Atlas (TCGA) was investigated for gene expression profile within CNS cancer data. Further analysis was done through cBioPortal and COSMIC to explore the QKI gene mutation(s). Moreover, QKI mRNA levels were evaluated by using SAGE Genie tools. The Kaplan-Meier Plotter was utilized to identify prognostic role of QKI mRNA levels in these cancers.
Results: Higher levels of QKI mRNA were detected in brain cancer tissues. Altered QKI gene expression was observed in 2% (56/2,958) of patients. Missense QKI gene mutation rate was 35.29%. The QKI gene alterations led to deleterious amino acid changes, including P181R, Q112P, and A220G. Altered QKI gene expression was significantly correlated with reduced survival rate (p<0.05).
Conclusion: The QKI gene is most expressed in brain tissues. In patients with gliomas, altered QKI expression/mutation is associated with a shorter survival rate. The findings of this study indicate that the QKI gene mutations can be considered as a potential prognostic biomarker for brain malignancies.