Changshu Hospital Affiliated to Nanjing University of Chinese Medicine, Changshu, China.
School of Integrated Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, China.
J Cell Mol Med. 2020 Mar;24(6):3359-3369. doi: 10.1111/jcmm.15009. Epub 2020 Jan 28.
The purpose of the present study was to evaluate the anti-cancer property of Lobetyolin on colorectal cancer and explore its potential mechanism. Lobetyolin was incubated with HCT-116 cells in the absence or presence of ASCT2 inhibitor Benser or p53 inhibitor Pifithrin-α. The levels of glutamine, glutamic acid, α-ketoglutarate, ATP and GSH were determined to measure the glutamine metabolism. Annexin V-FITC/PI staining and TUNEL assay were applied to estimate the apoptotic condition. The levels of ASCT2 were examined by RT-qPCR, Western blot and immunofluorescence staining. The expressions of cleaved-caspase-3, caspase-3, cleaved-caspase-7, caspase-7, cleaved-PARP, PARP, p53, p21, bax and survivin were detected using Western blot analysis. As a result, the treatment with Lobetyolin effectively induced apoptosis and glutamine metabolism in HCT-116 cells through ASCT2 signalling. The inhibition of ASCT2 reduced the glutamine-related biomarkers and augmented the apoptotic process. We further found that the effect of Lobetyolin on HCT-116 was related to the expressions of p21 and bax, and transportation of p53 to nucleus. The inhibition of p53 by Pifithrin-α promoted the inhibitory effect of Lobetyolin on ASCT2-mediated apoptosis. Lobetyolin also exerted anti-cancer property in nude mice. In conclusion, the present work suggested that Lobetyolin could induce the apoptosis via the inhibition of ASCT2-mediated glutamine metabolism, which was possibly governed by p53.
本研究旨在评估洛贝替定对结直肠癌的抗癌特性,并探讨其潜在机制。将洛贝替定与 HCT-116 细胞孵育,有无 ASCT2 抑制剂 Benser 或 p53 抑制剂 Pifithrin-α。测定谷氨酰胺、谷氨酸、α-酮戊二酸、ATP 和 GSH 的水平,以测量谷氨酰胺代谢。用 Annexin V-FITC/PI 染色和 TUNEL 测定法评估凋亡情况。通过 RT-qPCR、Western blot 和免疫荧光染色检测 ASCT2 水平。用 Western blot 分析检测 cleaved-caspase-3、caspase-3、cleaved-caspase-7、caspase-7、cleaved-PARP、PARP、p53、p21、bax 和 survivin 的表达。结果表明,洛贝替定通过 ASCT2 信号通路有效诱导 HCT-116 细胞凋亡和谷氨酰胺代谢。ASCT2 的抑制减少了与谷氨酰胺相关的生物标志物,并增强了凋亡过程。我们进一步发现,洛贝替定对 HCT-116 的作用与 p21 和 bax 的表达以及 p53 向核内的运输有关。用 Pifithrin-α 抑制 p53 促进了洛贝替定对 ASCT2 介导的凋亡的抑制作用。洛贝替定在裸鼠中也表现出抗癌特性。总之,本研究表明,洛贝替定可以通过抑制 ASCT2 介导的谷氨酰胺代谢诱导细胞凋亡,这可能受 p53 调控。