CENP-E变异体在不同肿瘤细胞株及癌组织中的表达差异

目的研究CENP-E变异体(CENP-EⅠ)在不同肿瘤细胞株及癌组织和相应的癌旁组织中的表达情况。方法应用巢式RT-PCR检测14个细胞株和17份癌组织及相应癌旁组织标本中CENP-EⅠmRNA(缺失第38个外显子)的表达情况,并比较变异体和野生型CENP-E(CENP-EWT) mRNA的表达差异;应用巢式PCR检测上述标本中CENP-E在DNA水平上的变异;并通过细胞增殖试验、细胞周期检测和染色体核型鉴定,分析CENP-EⅠ与细胞恶性程度的相关性。结果 RT-PCR结果显示,实验样本中CENP-E mRNA均有CENP-EWT和CENP-EⅠ两种形式同时存在于一种组织或细胞中,且在正常细胞株和癌旁组织中CENP-EWT表达量较高,在肿瘤细胞株和癌组织中CENP-EⅠ表达量较高,且差异有统计学意义(P<0.05);样本中CENP-E在DNA水平上不存在第38个外显子缺失,且细胞间CENP-E表达量的差异无统计学意义(P>0.05);CENP-EⅠ与细胞的恶性程度有一定的相关性。结论同一细胞内存在2种或2种以上形式的CENP-E mRNA,CENP-E变异体可能与肿瘤的发生有关。

Difference in Expressions of CENP-E Variant in Various Tumor Cell Strains and Carcinoma Tissues

Objective To investigate the expressions of CENP-EⅠ,a CENP-E variant,in various tumor cell strains as well as peri-cancerous and carcinoma tissues.Methods The expressions of mRNA of CENP-EⅠ,a CENP-E variant with deletion of the 38th exon,in 14 cell strains as well as 17 carcinoma tissue specimens and their corresponding peri-cancerous tissue specimens were determined by nested RT-PCR,and compared with those of wild type CENP-E(CENP-EWT).The variations of CENP-E at DNA level in the above-mentioned specimens were determined by nested PCR.The relationship of CENP-EⅠ to the malignant degree of cells were analyzed by cell proliferation test,determination of cell cycle and identification of chromosome karyotype.Results RT-PCR proved that both CENP-EWT and CENP-EⅠexisted in the same tissue or cell strain.CENP-EWT was highly expressed in normal cell strains and peri-cancerous tissues,while CENP-EⅠ in tumor cell strains and carcinoma tissues,which showed significant difference(P < 0.05).No deletion of the 38th exon at DNA level was observed in the specimens,and the expression levels of CENP-E in various cells showed no significant difference.However,CENP-EⅠ showed a certain relationship to the malignant degree of cells.Conclusion The CENP-E mRNA in not less than two forms may exist in the same cell strain,and CENP-E variant may be related to tumorigenesis.