Low expression of insulin-like growth factor binding protein 7 associated with poor prognosis in human glioma

Objectives: To investigate insulin-like growth factor binding protein 7 (IGFBP7) mRNA levels in human glioma and normal brain tissue, and to determine their clinical significance. Methods: In this retrospective study, IGFBP7 mRNA was quantified by real-time reverse transcription-polymerase chain reaction in brain tissue samples from patients with glioma and normal control subjects. Kaplan-Meier and Cox proportional hazards analyses were performed to determine any clinical and prognostic associations. Results: IGFBP7 mRNA levels were significantly lower in glioma tissue (n = 120) than in normal brain tissue (n = 20). Low (i.e. below the median, 5.9) IGFBP7 mRNA levels were significantly associated with larger tumour size (>= 5 cm, compared with <5 cm, diameter). Patients with high (above median) IGFBP7 had longer overall survival than those with low IGFBP7. Tumour grade and IGFBP7 mRNA level were independent predictors of overall survival. Conclusions: IGFBP7 downregulation is associated with poor prognosis in glioma, and this molecule may represent both a prognostic marker and a potential therapeutic target.