目的:探究本实验室前期工作发现的膀胱癌患者肿瘤组织中DNA拷贝数高频率改变的5个基因片段是否为中国(汉族)人膀胱癌特征性的异常改变。方法:针对上述5个DNA片段:CEP63、FOSL2、GHR、PAQR6、ZFAND3,采用实时荧光定量PCR技术,分析比较它们在白种人来源的商品化基因组DNA、30例健康中国汉族人外周血白细胞、51例膀胱癌患者肿瘤组织及配对的外周血白细胞的基因组DNA样品中拷贝数改变的情况。结果:除z明ⅣD3外,另外4个基因在白种人商品化基因组DNA与中国健康人外周血白细胞样品之间均存在DNA片段拷贝数差异。与中国健康人外周血白细胞相比,膀胱癌患者肿瘤组织中CEP63、GHR和PAQR6DNA片段拷贝数均增加(P均〈0.05),FOSL2和ZFAND3拷贝数均无显著改变(P均〉0.05);膀胱癌患者的外周血白细胞样品中CEP63和剧鲫辞荸贝数均增加(P均〈0.01),FOSL2和ZFAND3拷贝数均减少(P均〈0.01),而GHR拷贝数无显著改变(P=0.220)。与膀胱癌患者自身外周血白细胞基因组DNA相比,在肿瘤组织中,CEP63、FOSL2、GHR和ZFAND3拷贝数均增加(P均〈0.01),而PAQR6拷贝数无显著改变衅0.325)。结论:基因CEP63、FOSL2、GHR和PAQR6在中国汉族人与白种人之间存在DNA片段拷贝数差异。在汉族人中,CEP63、GHR基因片段的拷贝数增加很可能是在膀胱癌发生发展过程中获得的基因异常改变;而PAQR6拷贝数增加则可能是膀胱癌患者所携带的遗传变异。
OBJECTIVE: To explore whether the DNA copy number changes in 5 gene fragments are specific abnormalities for bladder cancer in Chinese patients. METHODS: Real-time PCR was conducted to gauge DNA copy number alteration of the 5 gene fragments among commercial genome DNA of peripheral blood leucocyte (PBL) derived from Caucasian, genome DNA of PBL from Chinese healthy volunteers, the bladder cancer patients and their corresponding tumor tissues. RESULTS: Comparing with the Caucasian PBL, all the gene fragments revealed copy number changes with decreased CEP63, increased FOSL2, GHR and PAQR6, in the PBL of Chinese healthy volunteers, except ZFAND3. Comparing with the PBL of Chinese healthy volunteers, in the bladder tumor tissue samples, the copy number of CEP63, GHR and PAQR6 increased (all P〈0.05); whereas FOSL2 (P=0.41) and ZFAND32 (P=0.062) revealed no statistical difference (all P〉0.05). Comparing with the PBL of Chinese healthy volunteers, the copy number of CEP63 and PAQR6 increased but FOSL2 and ZFAND3 decreased in the PBL of bladder cancer patients (all P〈0.01). Comparing with the PBL of the bladder cancer patients, gain of copy number was observed with CEP63, FOSL2, GHR and ZFAND3 (all P〈0.01), while PAQR6 (P=0.325) exhibited no statistical difference, in the corresponding tumor tissues. CONCLUSION: Copy number variation of CEP63, FOSL2, GHR and PAQR6 was found between Chinese (Han) and Caucasian. Copy number gain of CEP63 and GHR may be involved in carcinogenesis of bladder cancer; while gain of PAQR6 was possibly associated with the genetic susceptibility for this malignancy.