ROR1 MRNA EXPRESSION IN GLIOMA - A NOVEL PROGNOSTIC BIOMARKER

Abstract

Abstract AIMS Glioblastoma is the most common and aggressive primary brain tumour in adults. Despite maximal surgical resection followed by concomitant chemo-/radiotherapy, the three-year survival remains less than 5%. Receptor tyrosine kinase-like orphan receptor 1 (ROR1) overexpression is associated with poor prognosis in several cancers. ROR1 therapeutics are in Phase I/II clinical trials making it an exciting novel target with translational potential to explore for glioblastoma treatment. The aim of this study was to examine the association between ROR1 mRNA expression and overall survival (OS), by applying the WHO 2021 classification of transcriptomic glioma datasets. METHOD Clinical, histological, and molecular data were extracted from four independent glioma datasets (TCGA, CGGA, Rembrandt, and Gravendeel) via the GlioVis portal and analysed using the WHO 2021 classification. Only confirmed cases of astrocytoma, oligodendroglioma, or glioblastoma, and ROR1 mRNA expression data were included (2,216 cases). Kaplan-Meier survival curves were produced for OS with low/high grade glioma versus ROR1 mRNA expression. Log-rank (Mantel-Cox) multivariate regression was applied to analyse the effect of selected covariates on OS and ROR1 mRNA expression. RESULTS We observed a significant decrease in median OS in patients with high-ROR1 mRNA expression when compared to the low-ROR1 mRNA expression cohort (20 and 70 months, respectively). High-grade gliomas represented the highest ROR1 mRNA expression across the consortium, resulting in a poor median OS of 16 months. CONCLUSION This study represents the first report of an association between OS and the oncogenic role of ROR1 in glioma, a targetable cell surface marker for novel putative treatment in glioblastoma.