Zhu Dengyan, Yu Yang, Qi Yu, Wu Kai, Liu Donglei, Yang Yang, Zhang Chunyang, Zhao Song
Department of Thoracic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhous, China.
Department of Anesthesiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
Front Oncol. 2019 May 7;9:350. doi: 10.3389/fonc.2019.00350. eCollection 2019.
Long non-coding RNA CASC2 (lncRNA CASC2) has been found to be down-regulated in esophageal squamous cell carcinoma (ESCC). However, the effect of CASC2 on cisplatin-treated ESCC was unclear. The present study aimed to evaluate the role of CASC2 in cisplatin-treated ESCC cells. The expression levels of CASC2 and miR-181a were detected by qRT-PCR. Cell viability was measured by MTT assay. The cytotoxicity effect was detected by lactate dehydrogenase (LDH) release assay. Cell apoptosis was tested by flow cytometry. The protein levels of protein kinase B (Akt) and p-Akt were detected by western blotting. The results showed that CASC2 was low-expressed in ESCC cell lines. Overexpression of CASC2 enhanced the inhibitory effect of cisplatin on cell viability and promoted cisplatin-induced LDH release and apoptosis. We also found that miR-181a expression levels were increased in ESCC cell lines. MiR-181a inhibitor enhanced the antitumor activity of cisplatin, which was similar with the effect of CASC2. CASC2 directly interacted with miR-181a and inhibited the miR-181a expression. MiR-181a reversed the effects of CASC2 on antitumor activity of cisplatin. In addition, we also found that CASC2 suppressed the Akt pathway by inhibiting miR-181a. CASC2 promoted the antitumor activity of cisplatin through inhibiting Akt pathway via negatively regulating miR-181a in ESCC cells. The results provide a new insight for ESCC therapy.
长链非编码RNA CASC2（lncRNA CASC2）已被发现在食管鳞状细胞癌（ESCC）中表达下调。然而，CASC2对顺铂治疗的ESCC的影响尚不清楚。本研究旨在评估CASC2在顺铂治疗的ESCC细胞中的作用。通过qRT-PCR检测CASC2和miR-181a的表达水平。采用MTT法测定细胞活力。通过乳酸脱氢酶（LDH）释放试验检测细胞毒性作用。采用流式细胞术检测细胞凋亡。通过蛋白质印迹法检测蛋白激酶B（Akt）和磷酸化Akt（p-Akt）的蛋白水平。结果显示，CASC2在ESCC细胞系中低表达。CASC2的过表达增强了顺铂对细胞活力的抑制作用，并促进了顺铂诱导的LDH释放和细胞凋亡。我们还发现ESCC细胞系中miR-181a表达水平升高。miR-181a抑制剂增强了顺铂的抗肿瘤活性，这与CASC2的作用相似。CASC2直接与miR-181a相互作用并抑制miR-181a的表达。miR-181a逆转了CASC2对顺铂抗肿瘤活性的影响。此外，我们还发现CASC2通过抑制miR-181a来抑制Akt信号通路。在ESCC细胞中，CASC2通过负向调节miR-181a抑制Akt信号通路，从而促进顺铂的抗肿瘤活性。这些结果为ESCC治疗提供了新的见解。
