Division of Surgical Oncology, Department of Surgery, Medical College of Wisconsin, Milwaukee, WI, United States of America.
Department of Surgery, Tulane University School of Medicine, New Orleans, LA, United States of America.
PLoS One. 2019 Mar 14;14(3):e0213776. doi: 10.1371/journal.pone.0213776. eCollection 2019.
High-risk neuroblastoma (NB) is lethal childhood cancer. Published data including ours have reported the anti-proliferative effect of Xanthohumol (XN), a prenylated chalcone, in various cancer types suggesting that XN could be a useful small molecule compound against cancer. The TNF-Related Apoptosis-Inducing Ligand (TRAIL) is an endogenous ligand that is expressed in various immune cells. TRAIL mediates apoptosis through binding of transmembrane receptors, death receptor 4 (DR4) and/or death receptor 5 (DR5). Cancer cells are frequently resistant to TRAIL-mediated apoptosis, and the cause of this may be decreased expression of death receptors. This study aimed to identify combination therapies that exploit XN for NB. First, the effect of XN on cellular proliferation in human NB cell lines NGP, SH-SY-5Y, and SK-N-AS were determined via MTT assay, colony forming assay, and real-time live cell imaging confluency. XN treatment causes a statistically significant decrease in the viability of NB cells with IC50 values of approximately 12 μM for all three cell lines. Inhibition of cell proliferation via apoptosis was evidenced by an increase in pro-apoptotic markers (cleaved PARP, cleaved caspase-3/-7, and Bax) and a decrease in an anti-apoptotic marker, Bcl-2. Importantly, XN treatment inhibited PI3K/Akt pathway and associated with increased expression of DR5 by both mRNA and protein levels. Furthermore, a statistically significant synergistic reduction was observed following combination treatment (50%) compared to either TRAIL (5%) or XN (15%) alone in SK-N-AS cells. Therefore, this study shows XN treatment reduces NB cell growth via apoptosis in a dose-dependent manner, and enhanced growth reduction was observed in combination with TRAIL. This is the first study to demonstrate that XN alters the expression of DR5 as well as the synergistic effect of XN on TRAIL in NB and provides a strong rationale for further preclinical analysis.
高危神经母细胞瘤（NB）是一种致命的儿童癌症。包括我们在内的已发表数据报告了黄烷酮（XN），一种 prenylated chalcone，在各种癌症类型中的抗增殖作用，这表明 XN 可能是一种对抗癌症的有用小分子化合物。肿瘤坏死因子相关凋亡诱导配体（TRAIL）是一种内源性配体，在各种免疫细胞中表达。TRAIL 通过与跨膜受体、死亡受体 4（DR4）和/或死亡受体 5（DR5）结合来介导细胞凋亡。癌细胞通常对 TRAIL 介导的细胞凋亡具有抗性，其原因可能是死亡受体表达减少。本研究旨在确定利用 XN 治疗 NB 的联合治疗方法。首先，通过 MTT 测定法、集落形成测定法和实时活细胞成像细胞密度法，确定 XN 对人 NB 细胞系 NGP、SH-SY-5Y 和 SK-N-AS 中细胞增殖的影响。XN 处理导致所有三种细胞系的 NB 细胞活力均呈统计学显著下降，IC50 值约为 12 μM。通过增加促凋亡标志物（裂解 PARP、裂解 caspase-3/-7 和 Bax）和减少抗凋亡标志物 Bcl-2，证明了通过凋亡抑制细胞增殖。重要的是，XN 处理抑制了 PI3K/Akt 通路，并与 DR5 的 mRNA 和蛋白水平的表达增加相关。此外，与 TRAIL（5%）或 XN（15%）单独处理相比，SK-N-AS 细胞联合治疗（50%）观察到统计学上显著的协同减少。因此，本研究表明 XN 以剂量依赖性方式降低 NB 细胞生长，并且与 TRAIL 联合使用观察到增强的生长减少。这是第一项表明 XN 改变 DR5 表达以及 XN 在 NB 中对 TRAIL 的协同作用的研究，为进一步的临床前分析提供了强有力的依据。
