Wan Weiqing, Xu Xiaoqing, Jia Guijun, Li Wenmei, Wang Junmei, Ren Tong, Wu Zhen, Zhang Junting, Zhang Liwei, Lu Youyong
Department of Neurosurgery, Beijing Tiantan Hospital Capital Medical University, No,6 Tiantan Xili, Dongcheng District, 100050 Beijing, People's Republic of China.
World J Surg Oncol. 2014 Jun 14;12:185. doi: 10.1186/1477-7819-12-185.
Malignant gliomas are the most common form of primary malignant brain tumor. It has recently been suggested that genetic changes are involved in the progression of malignant gliomas. In previous studies, a novel gene, p42.3, was characterized as a tumor-specific gene that encodes a mitosis phase-dependent expression protein which is expressed in gastric cancer, but not in matched normal tissues.
In a series of 200 human brain gliomas and 13 normal tissues, we performed RT-PCR and mRNA in situ hybridization for analysis of p42.3 gene expression in gliomas, including astrocytoma (grade 2), oligoastrocytomas (grade 2), anaplastic oligoastrocytomas (grade 3), glioblastomas (grade 4) and normal tissues. Also, the mRNA expression was detected in gliomas by in situ hybridization. After producing polyclonal antibody to p42.3, we further tested p42.3 protein expression in astrocytomas and glioblastomas by immunohistochemistry and Western blot analysis.
Our results demonstrated that overexpression of the p42.3 gene is detected in gliomas, but not in normal brain tissues. Importantly, p42.3 mRNA expression is correlated with the pathological features of gliomas. In addition, p42.3 protein is expressed in both the cytoplasm and the nucleus in astrocytomas, whereas this protein appeared in the cytoplasm in glioblastomas.
These results indicate that p42.3 might be involved in carcinogenesis as a potential molecular marker for malignant gliomas.
恶性胶质瘤是原发性恶性脑肿瘤最常见的形式。最近有研究表明,基因改变参与了恶性胶质瘤的进展。在先前的研究中,一个新基因p42.3被鉴定为肿瘤特异性基因,它编码一种有丝分裂期依赖性表达蛋白,该蛋白在胃癌中表达,但在配对的正常组织中不表达。
我们对200例人脑胶质瘤和13例正常组织进行了逆转录聚合酶链反应(RT-PCR)和mRNA原位杂交,以分析p42.3基因在胶质瘤(包括二级星形细胞瘤、二级少突星形细胞瘤、三级间变性少突星形细胞瘤、四级胶质母细胞瘤)和正常组织中的表达。此外,通过原位杂交检测胶质瘤中的mRNA表达。在制备了针对p42.3的多克隆抗体后,我们通过免疫组织化学和蛋白质印迹分析进一步检测了p42.3蛋白在星形细胞瘤和胶质母细胞瘤中的表达。
我们的结果表明,在胶质瘤中检测到p42.3基因的过表达,但在正常脑组织中未检测到。重要的是,p42.3 mRNA表达与胶质瘤的病理特征相关。此外,p42.3蛋白在星形细胞瘤的细胞质和细胞核中均有表达,而在胶质母细胞瘤中该蛋白仅出现在细胞质中。
这些结果表明,p42.3可能作为恶性胶质瘤的潜在分子标志物参与肿瘤发生。