Objective To explore the application of serum osteopontin (OPN) and glial fibrillary acidic protein (GFAP) in the diagnosis of brain glioma and their relationships with pathological grade.

Methods A total of 83 patients with brain glioma were included in brain glioma group. Another 20 patients with intracranial benign tumors were selected and included in intracranial benign tumor group, and 20 healthy people who underwent physical examinations were included in control group. All subjects were tested for serum OPN and GFAP levels. The diagnostic value of serum indexes for diseases was evaluated by receiver operating characteristic(ROC) curve. The differences of serum OPN and GFAP levels in patients with brain glioma with different pathological characteristics were compared, the relationship between serum indexes and pathological grade was analyze, and the changes of serum OPN and GFAP levels before and after treatment were explored.

Results The expression levels of serum OPN and GFAP in the brain glioma group were higher than those in the intracranial benign tumor group and the control group (P < 0.05); the area under ROC curve of the combined detection of serum OPN and GFAP was 0.883, which was higher than OPN(0.793), GFAP(0.789) alone (P < 0.05). There were no significant differences in serum OPN and GFAP levels in different gender, age, tumor location, tumor diameter, Karnofsky Performance Status (KPS) score (P>0.05); the levels of serum OPN in brain glioma patients classified by World Health Organization (WHO) as grade Ⅲ to Ⅳ, mutation of tumor suppressor gene P53 genotype and high expression of cell proliferative active antigen Ki-67 were higher than those in brain glioma patients classified by WHO as grade Ⅰ to Ⅱ, wild-type P53 genotype and low expression of Ki-67(P < 0.05). The area under ROC curve for diagnosis of grade Ⅲ to Ⅳ glioma by combined detection was 0.792, which was higher than OPN (0.690) or GFAP (0.702) alone (P < 0.05). The serum levels of OPN and GFAP in WHO grade Ⅰ to Ⅱ and Ⅲ to Ⅳ glioma patients on the 14th day after surgery were lower than those before treatment, and the serum levels of OPN and GFAP were further reduced after radiotherapy and chemotherapy, the differences were statistically significant (P < 0.05). The levels of serum OPN and GFAP in patients with WHO grade Ⅲ to Ⅳ glioma before surgery, 2 weeks after surgery and 6 months after surgery were higher than those in patients with grade Ⅰ to Ⅱ (P < 0.05).

Conclusion Patients with brain glioma have high expression of serum OPN and GFAP, high expression of serum OPN and low expression of GFAP indicate high malignancy of glioma.