慢性髓细胞白血病增殖细胞核抗原基因的异常表达

Overexpression of proliferating cell nuclear antigen in chronic myelogenous leukemia

目的了解慢性髓细胞白血病(CML)基因表达谱规律,对在CML中高表达的PCNA基因进行分析鉴定。方法应用基因表达谱芯片技术,对CML患者和正常人的外周血单个核细胞(PBMC)基因表达差异进行分析。对于其中表达显著上调的增殖细胞核抗原(PCNA)基因,根据其核苷酸序列设计并合成该基因序列特异性引物,以CMLPBMC的总RNA为模板,RT-PCR技术扩增PCNA基因;用蛋白印迹法分析PCNA蛋白的表达。结果从4096个基因中筛选出差异表达基因共591条,其中288条基因表达增强,303条基因表达降低。在表达增高的基因中,PCNA表达增高8.725倍。在病人的标本中扩增出PC-NA基因,蛋白印迹证明CML病人PCNA蛋白表达增高。结论基因表达谱芯片检测发现CML中PCNA基因高表达,并在 mRNA转录水平及蛋白表达水平证明其异常表达,提示PCNA的表达增高与CML的发病存在一定的关系。

Objective To learn the regulation of gene expression profiles of peripheral blood mononuclear cells （PBMC） in patients with chronic myelogenous leukemia （ CML）, and to identify the expression of proliferating cell nuclear antigen （PCNA） gene in CML. Methods The changes of gene expression between the groups of 9 CML patients and 20 normal donors were assessed by using cDNA microarray consisting of 4096 different human genes to analyze the labeled cDNAs of PBMC. Then the probe of PCNA gene was designed and synthesized according to its DNA sequence to demonstrate the overexpression on transcription level by RT-PCR and on translation level by Western blotting. Results Compared with control group, a total of 591 genes were altered significantly on mRNA level in CML patients. The expressions of 288 genes showed 2-fold to 51.8-fold up-regulation while the expressions of 303 genes showed 2-fold to 33.3- fold down-regulation. Among them the expression of PCNA gene was up-regulated 8. 725-fold. The gene was amplified from patients RNA directly and the protein of PCNA was also proved in PBMC of CML patients. Conclusion PCNA gene was successfully screened in CML patients by DNA microarray. The finding indicated that this gene play an important role in cell malignant proliferation, which might well account for parts of the molecular mechanism of CML.