MPC-06 LRG1 HAS MULTIPLE POTENTIAL FOR CLINICOPATHOLOGICAL BIOMARKER OF GLIOBLASTOMA

Abstract BACKGROUND AND AIM Leucine-rich α-2 glycoprotein 1 (LRG1) is one of the candidate proteins as a diagnostic marker for glioblastoma. Although association with angiogenesis has been reported, it has been suggested that the role as a biomarker differs depending on the tumor types. The role of LRG1 as a biomarker in glioblastoma was examined clinicopathologically. METHODS Tumor tissues of 156 cases diagnosed as diffuse glioma (27 astrocytomas, 15 oligodendrogliomas, 114 glioblastomas) according to WHO 2016 classification at Kurume University from January 2001 to April 2019 were used. The immunohistochemical intensity of LRG1 was scoring as 4 stages and classified into 2 groups; score 0–1 was defined as low expression and score 2–3 was defined as high expression. Mutations of IDH1/2 and TERT promoter were analyzed by Sanger method. In glioblastoma, the relationship between LRG1 expression and clinical parameters such as age, preoperative Karnofsky Performance Scale, tumor location, extent of resection, MGMT promoter, and prognosis were examined. RESULTS LRG1 high expression rate was 41.2% (47/114) in glioblastoma, 3.7% (1/27) in astrocytoma, 20% (3/15) in oligodendroglioma, and glioblastoma showed significant higher expression level of LRG1 compared with lower-grade glioma (p = 0.0003). High expression of LRG1 was an independent favorable prognostic factor (HR 0.41, 95% CI 0.18–0.86, p=0.019) in IDH-wildtype glioblastoma, and correlated with gross total resection (p = 0.002) and the tumor location of the non-subventricular zone (SVZ) (p = 0.00007). CONCLUSION LRG1 demonstrated multiple potential as diagnostic, prognostic, and regional biomarker for glioblastoma.