To investigate the clinical significance of abnormal expression of melanoma-associated antigen D2 (MAGED2) in peripheral serum and cerebrospinal fluid of glioma patients.

Brain tumor specimens from 58 glioma patients pathologically confirmed at the Affiliated Cancer Hospital of Guangxi Medical University from January 2020 to December 2022 were collected as the observation group. A total of 20 non-tumor specimens derived from epileptic patients with resected lesions and surrounding brain tissue served as controls. Western blotting and immunohistochemistry were used to detect the expression level of MAGED2 in brain tissue specimens from glioma and non-tumor patients. The serum and postoperative cerebrospinal fluid were collected from the two groups, and the MAGED2 expression levels were detected by enzyme linked immunosorbent assay (ELISA). The differences in MAGED2 expression levels between two groups were compared. The correlation between the expression levels of MAGED2 in serum and cerebrospinal fluid and the tumor grade and prognosis was analyzed. The different prognostic parameters were analyzed by multifactorial analysis using Cox proportional risk model.

Western blotting revealed that MAGED2 protein expression was higher in glioblastoma (1.07±0.27), diffuse astrocytoma (1.05±0.19), mesenchymal astrocytoma (0.83±0.06) and oligodendroglioma (0.68±0.07) than that of the non-tumor brain tissue group (0.39±0.07), and the difference was statistically significant (F=45.88, P<0.001). Immunohistochemical detection of MAGED2 protein stained predominantly in the cytoplasm and nucleus. ELISA detected the preoperative serum MAGED2 expression level, and serum MAGED2 expression level in the observation group [(1 051.20±129.33) pg/ml] was significantly higher than that in the control group [(207.62±23.39) pg/ml, t=17.22, P<0.01]. The postoperative serum MAGED2 expression level in the observation group (556.40±59.77) was significantly lower than that in the preoperative period (1 051.20±129.33, t=14.67, P<0.01). The serum MAGED2 expression level of patients after surgery [(556.40±59.77) pg/ml] was still significantly higher than that in the control group [(207.6±23.39) pg/ml], and the difference was statistically significant (t=6.144, P<0.01). MAGED2 was positively correlated with each other in terms of its expression in preoperative serum, postoperative serum, and postoperative cerebrospinal fluid of patients in the observation group (r=0.19, 0.33, 0.46, P<0.01). Kaplan-Meier analysis showed that the overall survival (OS) of patients in the high MAGED2 protein expression group was lower than that in the low expression group (50.00 weeks vs. 250.00 weeks, χ²=22.13, P<0.001). OS in the preoperative serum MAGED2 high-expression group was lower than that in the low-expression group (94.00 weeks vs. 212.00 weeks, χ²=12.45, P<0.001). OS in the postoperative serum MAGED2 high-expression group was lower than that in the low-expression group (150.00 weeks vs. 233.00 weeks, χ²=4.34, P<0.05). OS in the postoperative cerebrospinal fluid MAGED2 high-expression group was lower than that in the low-expression group (132.00 weeks vs. 250.00 weeks, χ²=10.53, P<0.05). Multifactorial analysis using the Cox proportional risk model showed that MAGED2 was an independent prognostic factor for glioma patients [hazard ratio (HR)=0.578, 95% confidence interval (CI): 0.182-0.927, P<0.05].

MAGED2 is expected to be a liquid biopsy biological marker for assessing glioma progression, pathological grade and prognosis.

Glioma; Melanoma-associated Antigen D2; Serum; Cerebrospinal fluid; Biological markers