【摘要】 目的探究基于miR-20a为探针调控ST8SIA2在结直肠癌耐药中的功能和机制,为寻求逆转药物提供新的治疗策略及靶点。方法采用RT-PCR、Western blot分别检测结直肠癌Lovo细胞及其耐药细胞株Lovo/5-FU中miR-20a、ST8SIA2的表达水平;利用CCK-8及Western blot实验检测上调、下调mi R-20a后两种细胞株的药物敏感性及其ST8SIA2的表达情况;靶基因预测及双荧光素酶报告实验验证miR-20a与ST8SIA2的靶向关系;利用CCK-8实验进一步检测Lovo细胞中miR-20a和ST8SIA2表达调控对细胞药物敏感性的影响。结果①与Lovo细胞相比,miR-20a在耐药细胞株Lovo/5-FU中呈现高表达,ST8SIA2呈现低表达;②特异性上调Lovo细胞中miR-20a表达,ST8SIA2表达减弱,该细胞的药物敏感性减弱;③特异性下调Lovo/5-FU细胞中miR-20a表达,ST8SIA2表达增加,该细胞的药物敏感性增强;④特异性上调Lovo细胞中ST8SIA2表达,可逆转miR-20a对细胞产生的作用。结论 miR-20a及ST8SIA2的表达水平与结直肠癌耐药性密切相关,miR-20a可能是通过靶向负调控ST8SIA2的表达进而调控结直肠癌细胞的耐药。更多还原

【Abstract】 Objective We aim to explore the mechanism of miR-20 a to regulate ST8SIA2 in colorectal cancer drug resistance and to provide a novel therapeutic strategy and target of colorectal cancer.Methods The expression of miR-20 a and ST8SIA2 was analyzed by real-time PCR and Western blot in colorectal cancer cells. CCK-8 and Western blot assays were used to detect the drug sensitivity and the ST8SIA2 expression in the two cell lines after up-regulation and downregulation of miR-20 a, respectively. The interaction between miR-20 a and its predicted target gene ST8SIA2 was confirmed by 3’-UTR dual-luciferase reporter assay. The cell viability was obtained to further investigate the drug sensitivity of Lovo cells upon transfection with miR-20 a mimic and ST8SIA2. Results miR-20 a was highly expressed and ST8SIA2 lowly expressed in Lovo/5-FU cells. Overexpression of miR-20 a in Lovo cells could decrease ST8SIA2 level, and decrease the chemosensitivity to anti-tumor drugs. Silencing of miR-20 a in Lovo/5-FU cells resulted in the increased expression of ST8SIA2, and increased the chemosensitivity to anti-tumor drugs. Overexpression of ST8SIA2 could reversed the effect of miR-20 a mimic on drug resistance. Conclusion The levels of miR-20 a and ST8SIA2 were closely related to the drug resistance in colorectal cancer. miR-20 a could regulate drug resistance in colorectal cancer cells by targeting ST8SIA2 expression.更多还原