The Multipotential of Leucine-Rich α-2 Glycoprotein 1 as a Clinicopathological Biomarker of Glioblastoma

Leucine-rich alpha-2 glycoprotein 1 (LRG1) is a diagnostic marker candidate for glioblastoma. Although LRG1 has been associated with angiogenesis, it has been suggested that its biomarker role differs depending on the type of tumor. In this study, a clinicopathological examination of LRG1's role as a biomarker for glioblastoma was performed. We used tumor tissues of 155 cases with diffuse gliomas (27 astrocytomas, 14 oligodendrogliomas, 114 glioblastomas). The immunohistochemical LRG1 intensity scoring was classified into 2 groups: low expression and high expression. Mutations of IDH1, IDH2, and TERT promoter were analyzed through the Sanger method. We examined the relationship between LRG1 expression level in glioblastoma and clinical parameters, such as age, preoperative Karnofsky performance status, tumor location, extent of resection, O-6-methylguanine DNA methyltransferase promoter, and prognosis. LRG1 high expression rate was 41.2% in glioblastoma, 3.7% in astrocytoma, and 21.4% in oligodendroglioma. Glioblastoma showed a significantly higher LRG1 expression than lower-grade glioma (p = 0.0003). High expression of LRG1 was an independent favorable prognostic factor (p = 0.019) in IDH-wildtype glioblastoma and correlated with gross total resection (p = 0.002) and the tumor location on nonsubventricular zone (p = 0.00007). LRG1 demonstrated multiple potential as a diagnostic, prognostic, and regional biomarker for glioblastoma.