[Show abstract][Hide abstract] ABSTRACT: To examine the expression of N-methylpurine-DNA glycosylase (MPG) gene and protein in glioma samples with different WHO grades and its association with patients' survival.
Immunohistochemistry assay, quantitative real-time PCR and Western blot analysis were carried out to investigate the expression of MPG gene and protein in 128 glioma and 10 non-neoplastic brain tissues.
MPG gene expression level in glioma tissues was significantly higher than that in non-neoplastic brain tissues (P < 0.001). Immunohistochemistry also showed that MPG protein was over-expressed in glioma tissues, which was consistent with the resutls of Western blot analysis. Additionally, the expression levels of MPG gene and protein both increase from grade I to grade IV glioma according to the results of real-time PCR, immunohistochemistry and western blot analysis. Moreover, the survival rate of MPG-positive patients was significantly lower than that of MPG-negative patients (P < 0.001). We further confirmed that the over-expression of MPG was a significant and independent prognostic indicator in glioma by multivariate analysis (P < 0.001).
Our data showed the over-expression of MPG gene and protein in human gliomas, and also suggested for the first time that MPG be an unfavorable independent prognostic indicator for glioma patients.
BioMed Research International 01/2012; 2012:760679. · 2.71 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Gliomas are the most common primary intracranial tumors. Understanding the molecular basis of gliomas' progression is required to develop more effective therapies. The Wnt/β-catenin signaling cascade is an important signal transduction pathway in human cancers. Although, overactivation of this pathway is a hallmark of several forms of cancer, little is known about its role in human gliomas. Here, we aimed to determine the clinical significance of Wnt/β-catenin pathway components in gliomas. Immunohistochemical staining was performed to detect the expression patterns of Wnt1, β-catenin and Cyclin D1 in the biopsies from 96 patients with primary gliomas. Kaplan-Meier survival and Cox regression analyses were performed to evaluate the prognosis of patients. Cytoplasmic staining pattern of Wnt1, membranous, cytoplasmic and nuclear accumulation of β-catenin, and nuclear localization of Cyclin D1 were demonstrated by immunohistochemical staining. The Wnt1 expression significantly correlated with the expression of Cyclin D1 (P < 0.0001). The ratio of tumors with a cytoplasmic-nuclear pattern or a cytoplasmic pattern of β-catenin was significantly higher in Wnt1-positive (P < 0.01) and Cyclin D1-positive (P < 0.01) tumors than in Wnt1-negative and Cyclin D1-negative tumors, respectively. The protein expression levels of Wnt1, β-catenin and Cyclin D1 were all positively correlated with the Karnofsky performance scale (KPS) score and World Health Organization (WHO) grades of patients with gliomas. Furthermore, Wnt1, cytoplasmic-nuclear β-catenin and Cyclin D1 status were all the independent prognostic factors for glioma patients (P = 0.01, 0.007 and 0.005, respectively). These results provide convincing evidence that the Wnt/β-catenin pathway correlated closely with the progression of gliomas and might be a novel prognostic marker for this neoplasm.
Clinical and Experimental Medicine 06/2011; 11(2):105-12. · 2.82 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Bone morphogenetic protein-2 (BMP-2) is normally expressed in the embryo promoting the development of several organs. Aberrant expression of BMP-2 occurs in various tumors. However, a correlation between BMP-2 expression in human gliomas and patients' prognosis has not been reported. To address this question, this study was to investigate the BMP-2 expression pattern in human gliomas and to evaluate its prognostic relevance.
We analyzed the expression of the BMP-2 antigen in a series of 98 gliomas of various grade and histology by immunohistochemistry on paraffin-embedded sections. Then, the correlation of BMP-2 expression pattern with clinical-pathological features of patients and its prognostic relevance were determined.
Immunohistochemical analysis with anti-BMP-2 antibody revealed dense and spotty staining in the tumor cells and its expression levels became significantly higher as the gliomas' grade advanced (P < 0.001). The median survival of patients with intensively positive BMP-2 expression was significantly shorter than that with negative expression (318 vs. 1197 days, P < 0.0001). The Kaplan-Meier survival curves showed that the BMP-2 expression was not only a significant predictor of survival in high-grade gliomas (grade IV, P = 0.02), but also in lower-grade gliomas (grades II and III, P < 0.001).
These results indicate that BMP-2 is a highly sensitive marker for gliomas prognosis and suggest that the expression level of BMP-2 may be a potent tool for the clinical prognosis of gliomas patients.
Japanese Journal of Clinical Oncology 10/2009; 39(10):625-31. · 1.75 Impact Factor