F10 gene hypomethylation, a putative biomarker for glioma prognosis.
ABSTRACT Tumors are usually characterized by an imbalance in cytosine methylation, including hypomethylation of CpG islands. In this study, bisulfite sequencing PCR was used to assess the promoter methylation status of coagulation factor X (F10) gene in tumors of 96 glioma patients and in glioma cells U251, SF767, and SF126, and the effect of promoter hypomethylation on protein expression was evaluated immunohistochemically. The study showed that the demethylation ratio of F10 in SF126, SF767, and U251 cells was 38.6, 26.4, and 24.3% respectively. Hypomethylation of F10 was detected in 82.3% of glioma specimens and in no normal brain tissues, with significant correlation with its protein expression. However there was no remarkable relationship between F10 hypomethylation and sex, age, and advanced tumor grade. The correlation between F10 hypomethylation, protein expression, and overall survival (OS) was statistically significant. Hypomethylation of F10 promoter in gliomas accounted for F10 encoding protein FX overexpression and aggressive biological behavior in a subset of patients. Furthermore, in the F10 hypomethylation group, OS was shorter for patients with F10 overexpression than for those without. Detection of these epigenetic changes in tumors may provide important information regarding prognosis.
[Show abstract] [Hide abstract]
ABSTRACT: Metastasis associated in colon cancer 1 (MACC1) has been regarded as a novel potential therapeutic target for multiple cancers. However, the impact of MACC1 in glioma remains unclear. The aim of this study was to analyze the correlation of MACC1 expression with the clinicopathological features of glioma. MACC1 mRNA and protein expression levels in human glioma tissues were detected by quantitative real-time polymerase chain reaction and immunohistochemistry assays, respectively. MACC1 mRNA and protein expression were both significantly higher in glioma tissues than in corresponding noncancerous brain tissues (both P < 0.001). In addition, statistical analysis suggested that high MACC1 expression was significantly correlated with advanced pathological grade (P = 0.004) and that patients with high expression of MACC1 protein exhibited a poorer prognosis than those with low MACC1 expression. Furthermore, Cox multivariate analysis showed that MACC1 overexpression was an independent prognostic factor for predicting the overall survival of glioma patients. In conclusion, expression of MACC1 in glioma could be adopted as a candidate biomarker for the diagnosis of clinical stage and for assessing prognosis, indicating for the first time that MACC1 may play an important role in the tumor development and progression in glioma. MACC1 might be considered as a novel therapeutic target against this cancer.Tumor Biology 08/2013; DOI:10.1007/s13277-013-1112-5 · 2.84 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: Epigenetic mechanisms have important roles in carcinogenesis. We certified that the mRNA translation-related gene cytoplasmic polyadenylation element-binding protein 1 (CPEB1) is hypomethylated and overexpressed in glioma cells and tissues. The knockdown of CPEB1 reduced cell senescence by regulating the expression or distribution of p53 in glioma cells. CPEB1 is also regulated directly by the tumor suppressor miR-101, a potential marker of glioma. It is known that the histone methyltransferase enhancer of zeste homolog 2 (EZH2) and embryonic ectoderm development (EED) are direct targets of miR-101. We demonstrated that miR-101 downregulated the expression of CPEB1 through reversing the methylation status of the CPEB1 promoter by regulating the presence on the promoter of the methylation-related histones H3K4me2, H3K27me3, H3K9me3 and H4K20me3. The epigenetic regulation of H3K27me3 on CPEB1 promoter is mediated by EZH2 and EED. EZH2 has a role in the regulation of H3K4me2. Furthermore, the downregulation of CPEB1 induced senescence in a p53-dependent manner.Cell Death & Disease 06/2013; 4:e675. DOI:10.1038/cddis.2013.197 · 5.18 Impact Factor