EB病毒变异型EBER2对鼻咽癌细胞增殖和凋亡的影响

EB病毒(EBV)编码小RNA(EBERs,包括EBER1和EBER2)的致癌作用已在多种细胞系中得到证实,我们前期研究发现在EBER2基因发生6处突变的EB-8m变异型可能与鼻咽癌(NPC)的发生相关。本研究探讨变异型EBER2对NPC细胞增殖和凋亡的影响,以进一步明确EBER2基因变异在NPC发生中的作用。分别以B95-8原型和EB-8m变异型EBER2稳定转染EBV阴性NPC细胞系,MTT法和平板克隆检测细胞增殖,流式细胞仪检测细胞凋亡。与转染原型EBER2细胞及转染载体的对照细胞比较,转染变异型EBER2细胞的MTT吸光度值和平板克隆形成率增高,细胞凋亡率降低(P均小于0.05),原型和对照之间细胞增殖无差异,但原型的细胞凋亡率亦低于对照(P0.05)。上述结果表明,EB-8m变异型EBER2可通过提高NPC细胞增殖及抗凋亡能力而增强其致癌作用。

Effects of the Variant of Epstein-Barr Virus-Encoded RNA2 (EBER2) to Cell Proliferation and Apoptosis of Nasopharyngeal Carcinoma

It has been confirmed that EBV-encoded RNAs (EBERs, including EBER1 and EBER2) contribute to carcinogenesis in multiple cell lines. The previous researches demonstrated that EB-8m variant with 6 common mutants in the EBER2 gene area may be associated with nasopharyngeal carcinoma (NPC). This study aims to investigate the effects of EBER2 with EB-8m variant to the cell proliferation and apoptosis of EBV-negative NPC cell lines, and so as to further make certain the role of variant EBER2 in the biogenesis of NPC. In EBV-negative NPC cell lines (CNE1 and HONE1) with stable expression of EBER2 prototype (B95-8) or EB-8m variant gene and control cells with vector transfection, the cell proliferation was assessed by MTT test and plate clone forming assay, and the cell apoptosis was evaluated by flow cytometry. Comparison of infection prototype EBER2 cells with control cells of transfection vector, MTT absorbance value and plate clone formation rate increased, and cell apoptosis dampened (P all <0.05), the proliferation between prototype and control cell had no difference, however, the apoptosis rate of prototype also lower than control (P<0.05). The above mentioned results showed that EB-8m variant EBER2 could strengthen its carcinogenic effects through the increment of NPC cell proliferation and anti-apoptosis ability.