The correlation of bone morphogenetic protein 2 with poor prognosis in glioma patients

Glioma is the most common type of human intracranial cancers and has poor prognosis. Bone morphogenetic protein 2 (BMP2) plays important roles in cancer cell signalings (Vecht et al. Oncologist 19:751-9, 2014). Here, we aimed to investigate the correlation of BMP2 with patient prognosis as well as pathological indicators. Immunohistochemistry was used to test BMP2 proteins in 45 gliomas of distinct malignancy grade, and Kaplan-Meier survival analysis was performed to assess prognostic significance. BMP2 protein was also detected in cell lines by Western blot. We observed that BMP2 protein was stained in 44.4% (20 out of 45) of all glioma tissues, including 32.1% of low-grade (I + II) gliomas and 52.9% of high-grade (III + IV) gliomas. Grade IV gliomas potently expressed BMP2 proteins. Western blot showed BMP2 protein expressed in cell lines NHA, A172, T98G, U87, and U251. In addition, BMP2 expression was significantly associated with WHO grade (p = 0.024). According to log-rank test and Cox regression model, BMP2 can be suggested as an independent prognostic factor, apart from WHO grade. Taken together, BMP2 is differently highly expressed in different grades of gliomas and correlated to WHO grade. BMP2 also independently indicates poor prognosis in old glioma patients, which is indicative of an effectively therapeutic target.