摘要：

目的: 通过shRNA降低Livin基因的表达,研究口腔癌细胞Cal27对化疗药物5-氟尿嘧啶(5-fluorouracil, 5-FU)敏感性的改变,并探索其可能的机制,为口腔癌化疗耐受的靶向治疗提供新的治疗思路。方法: 设计针对Livin基因的shRNA序列,构建慢病毒shRNA表达载体,包装慢病毒颗粒并感染Cal27细胞,获得稳定沉默Livin基因的细胞株,使用20、40、60 μmmol/L的5-FU处理Livin沉默细胞和对照细胞24 h,通过流式细胞术测定细胞凋亡率,MTT法检测细胞活力。结果: 成功构建了针对Livin的shRNA质粒,并将其包装为慢病毒;降低Livin的表达水平后,Cal27细胞对5-FU的敏感性上升,凋亡率提高,细胞活力下降,Caspase 3表达量增高(均P<0.05)。结论: 通过慢病毒介导的shRNA降低了Cal27细胞Livin基因的表达,增加了Cal27对5-FU的敏感性,其机制与Livin对Caspase 3的抑制效果有关,这为口腔癌化疗耐受问题提供了新的治疗靶点。

关键词: 口腔癌, Livin, 化疗耐受, Caspase 3

Abstract:

Objective: To explore changing the sensitivity of Cal27 to 5-fluorouracil (5-FU) by downregulating the expression of Livin gene through shRNA and its potential mechanism, thus to provide new ideas to solve the chemoresistance of oral cancer. Method: ShRNA sequence targeting Livin was designed, and constructed into lentivirus expressing vector. Then, lentivirus was packed for affecting into Cal27 to get the stable Livin-silencing cell strain. After Cal27 cells in both control group and Livin-silencing group were treated with concentrations of 20, 40 and 60 μmmol/L 5-FU for 24 hours, the cell apoptosis rate and cell viability were measured by flow cytometry and MTT respectively. Results: The designed shRNA plasmid targeting Livin were successfully constructed and packed into lentivirus. After the expression level of Livin was knocked down, the sensitivity and cell apoptosis rate of Cal27 to 5-FU were elevated dramatically, and the cell viability decreased significantly and the expression of Caspase 3 was significantly decreased (all P<0.05). Conclusion: The expression level of Livin gene in Cal27 was downregulated by transfection with shRNA lentivirus, which increased the sensitivity of Cal27 to 5-FU. The underlying mechanism may be associated with the inhibitory effect of Livin on Caspase 3, which will provide a new target for solving chemoresistance of oral cancers.

Key words: oral cancer, Livin, chemoresistance, Caspase 3

中图分类号: 

• R782

• R739.8