Postgraduate Training Basement, Chinese People's Armed Police Force Characteristic Medical Center, Jinzhou Medical University.
Department of Gastroenterology, Chinese People's Armed Police Force Characteristic Medical Center.
Biol Pharm Bull. 2019;42(9):1500-1509. doi: 10.1248/bpb.b19-00174.
Cinobufagin isolated from traditional Chinese herbs has antitumour, anaesthetic, analgesic and anti-inflammatory effects. Recently, the antitumour activity of cinobufagin has attracted increasing attention from researchers. However, the anticancer activity of this drug on esophageal cancer cells and the precise mechanism are unclear. In this study, we determined the inhibitory effect of cinobufagin on the growth of three esophageal squamous cell carcinoma cell lines and explored its underlying mechanism. EC-109, Kyse-150, and Kyse-520 cells were treated with different concentrations of cinobufagin. The results of the Cell Counting Kit-8 (CCK-8) and clone formation assays showed that cinobufagin significantly reduced cell proliferation in a dose- and time-dependent manner. Also, flow cytometry and Hoechst 33342 staining indicated that the inhibition of growth induced by cinobufagin was mediated by G2/M cell cycle arrest and apoptosis. In addition, the expression of proteins related to cell cycle arrest and apoptosis was assessed by real-time quantitative (q)RT-PCR and Western blot. The results showed that cinobufagin caused G2/M arrest via upregulation of p21 and Wee1 and downregulation of cyclin B1 and Cdc2 at the mRNA and protein levels and induced apoptosis via upregulation of cleaved caspase-3, Puma and Noxa expression and an increased Bax/Bcl-2 ratio. Other data further showed that cinobufagin increased p73 expression and decreased Mdm2 expression, whereas p53 expression was not significantly changed. Taken together, these results suggest that growth inhibition of cinobufagin in esophageal cancer cells might act through the p73 pathway and its downstream molecules.
从传统中药中分离出的华蟾素具有抗肿瘤、麻醉、镇痛和抗炎作用。最近，华蟾素的抗肿瘤活性引起了研究人员越来越多的关注。然而，该药物对食管癌细胞的抗癌活性及其确切机制尚不清楚。在本研究中，我们测定了华蟾素对三种食管鳞癌细胞系生长的抑制作用，并探讨了其潜在的机制。用不同浓度的华蟾素处理 EC-109、Kyse-150 和 Kyse-520 细胞。CCK-8 和克隆形成实验结果表明，华蟾素呈剂量和时间依赖性显著降低细胞增殖。此外，流式细胞术和 Hoechst 33342 染色表明，华蟾素诱导的生长抑制是通过 G2/M 细胞周期阻滞和细胞凋亡介导的。此外，通过实时定量(q)RT-PCR 和 Western blot 评估了与细胞周期阻滞和凋亡相关的蛋白表达。结果表明，华蟾素通过上调 p21 和 Wee1 以及下调细胞周期蛋白 B1 和 Cdc2 的 mRNA 和蛋白水平引起 G2/M 期阻滞，并通过上调 cleaved caspase-3、Puma 和 Noxa 的表达以及增加 Bax/Bcl-2 比值诱导细胞凋亡。其他数据进一步表明，华蟾素增加了 p73 的表达，降低了 Mdm2 的表达，而 p53 的表达没有明显变化。综上所述，这些结果表明，华蟾素对食管癌细胞的生长抑制可能通过 p73 途径及其下游分子发挥作用。
