Slit2 and Robo1 expression as biomarkers for assessing prognosis in brain glioma patients

This study was conducted to investigate the clinical significance of Slit2 and Robo1 expression in prognosis of patients with brain gliomas.

Human brain tissue samples were collected from normal glial tissues (control), low- and high-grade glioma tissues. Slit2 and Robo1 expression levels in cells were assessed by an immunohistochemistry (IHC), and population of the Slit2- and Robo1-presenting patients was examined. The Slit2 and Robo1 mRNA expression levels in three types of the brain cells was determined by RT-PCR.

Slit2⁺ cell counts were decreased with increased Robo1⁺ cells in the low-grade and high-grade glioma tissues as compared to the control. The percentage of cells expressing Slit2 decreased from the control to the high-grade glioma and the percentage of cells expressing Robo1 in low- and high-grade gliomas was increased as compared to the control (P < 0.01). The decrease in the Slit2 mRNA expression was associated with the increase in the Robo1 mRNA expression in the low- and high-grade gliomas (P < 0.01 or 0.05). Survival time for patients with Slit2^-/Robo1⁺ gliomas was shorter than patients with Slit2⁺/Robo1⁺ gliomas in the investigated cohorts (P < 0.01).

Slit2 and Robo1 expression levels serve as a biomarker with utility in grading gliomas as well as predicting patient survival. The change in Slit2 expression is more reliable and effective than Robo1 expression in predicting a poor prognosis of brain glioma patients.