Wang Qiaosu, Zhang Wenjing, Hao Shaojuan
a The E.N.T Department , The First affiliated Hospital of Zhengzhou University , Zhengzhou , Henan , China.
Cell Cycle. 2017 Apr 18;16(8):795-801. doi: 10.1080/15384101.2017.1301334. Epub 2017 Mar 30.
Recent studies reported that long non-coding RNA (lncRNA) might play critical roles in regulating chemo-resistant of multiple types of cancer. This study aimed to investigate whether long non-coding RNA CCAT1 was involved in Paclitaxel resistance in nasopharyngeal carcinoma (NPC). qRT-PCR was used for testing the expression of CCAT1, miR-181a and CPEB2 in tumor tissues and NPC cancers. NPC cells were transfected with siRNAs to suppress the mRNA level of CCAT1 in NPC cells. MTT assays and flow cytometry analysis were used to assess the sensitivity of paclitaxel in NPC cells. Luciferase reporter assays were used to examine the interaction of CCAT1 or CPEB2 to miR-181a. Our findings revealed that the upregulated CCAT1 results in significantly enhancing paclitaxel resistance in nasopharyngeal cancer cells. Bioinformatics analysis and luciferase reporter assay indicated that the upregulated CCAT1 sponges miR-181a in NPC cells. Furthermore, RNA immuno-precipitation assays showed that miR-181a could directly bind to CCAT1 mRNA in NPC cells. We restored miR-181a in NPC cells, and found restoration of miR-181a re-sensitized the NPC cells to paclitaxel in vitro. In addition, our results also showed that miR-181a was a modulator of paclitaxel sensitivity due to its regulative effect on cell apoptosis via targeting CPEB2 in NPC cells. Taken together, lncRNA CCAT1 regulates the sensitivity of paclitaxel in NPC cells via miR-181a/CPEB2 axis.
最近的研究报道，长链非编码RNA（lncRNA）可能在调节多种癌症的化疗耐药性中发挥关键作用。本研究旨在探讨长链非编码RNA CCAT1是否参与鼻咽癌（NPC）的紫杉醇耐药性。采用qRT-PCR检测肿瘤组织和NPC癌细胞中CCAT1、miR-181a和CPEB2的表达。用小干扰RNA转染NPC细胞以抑制NPC细胞中CCAT1的mRNA水平。采用MTT法和流式细胞术分析评估NPC细胞对紫杉醇的敏感性。用荧光素酶报告基因检测法检测CCAT1或CPEB2与miR-181a的相互作用。我们的研究结果显示，CCAT1上调导致鼻咽癌细胞中紫杉醇耐药性显著增强。生物信息学分析和荧光素酶报告基因检测表明，NPC细胞中上调的CCAT1可吸附miR-181a。此外，RNA免疫沉淀试验表明，miR-181a可直接结合NPC细胞中的CCAT1 mRNA。我们在NPC细胞中恢复了miR-181a的表达，并发现恢复miR-181a的表达可使NPC细胞在体外对紫杉醇重新敏感。此外，我们的结果还表明，miR-181a是紫杉醇敏感性的调节因子，因为它通过靶向NPC细胞中的CPEB2对细胞凋亡具有调节作用。综上所述，lncRNA CCAT1通过miR-181a/CPEB2轴调节NPC细胞对紫杉醇的敏感性。
