Department of Biomedical and Neuromotor Sciences, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy.
Health Sciences and Technologies, Interdepartmental Centre for Industrial Research, University of Bologna, 40064 Ozzano dell'Emilia (BO), Italy.
Int J Med Sci. 2018 Jan 1;15(1):23-30. doi: 10.7150/ijms.22002. eCollection 2018.
α-Mangostin (αMG) is extracted from Garcinia mangostana Linn and exerts antiproliferative activities. Although several researches on αMG were performed using cell monolayers, the pharmacological effects on 3D cancer models have never been investigated. Aim of the present study was to find new anticancer properties of αMG by evaluating the changes that this compound provokes in multicellular tumour spheroids (MCTSs). MCTSs were generated from MDA-MB-231 and MCF-7 breast tumour cell lines and then treated with 0.1÷30 μg/ml αMG for 24 and 48 h. MCTS size, density, and cell migration were determined by software elaboration of phase contrast images captured by a digital camera. Cell viability was evaluated by resazurin and acid phosphatase assays, while cell apoptosis was assessed by a fluorescent assay of caspase activity. The distribution of living cells inside MCTSs was shown by live/dead fluorescence staining. A dose-dependent decrease in cell viability was obtained by treating MDA-MB-231 spheroids with αMG for 48 h (IC = 0.70-1.25 μg/ml). A significant reduction in spheroid volume, paralleled by its increased compactness, was observed only at concentration of 30 μg/ml, but not with lower doses of αMG. By contrast, αMG in the range of 5-15 μg/ml increased the size of MCTSs due to a parallel reduction in cell aggregation. The same window of concentrations was also able to stimulate cell apoptosis in a dose-dependent manner. Bimodal volumetric effects were also obtained by treating the spheroids generated from the MCF-7 cells with 0.1÷30 μg/ml αMG for 48 h. Finally, doses higher than 5 μg/ml caused a progressive impairment in cell migration from the edge of MDA-MB-231 MCTSs. After exposure at doses of αMG just above IC, MDA-MB-231 spheroids showed a significant reduction in cell adhesion that did not stimulate cell migration but, on the contrary, blunted cell motility. These findings suggest a novel anticancer feature of αMG that could be taken into consideration to improve conventional drug penetration into the tumour bulk.
α-倒捻子素（αMG）从藤黄属中提取，具有抗增殖活性。尽管已经使用细胞单层进行了几项关于αMG 的研究，但从未研究过该化合物对 3D 癌症模型的药理作用。本研究的目的是通过评估该化合物在多细胞肿瘤球体（MCTS）中引起的变化来发现αMG 的新抗癌特性。从 MDA-MB-231 和 MCF-7 乳腺癌细胞系生成 MCTS，然后用 0.1÷30 μg/ml αMG 处理 24 和 48 h。通过软件对数码相机拍摄的相差图像进行处理来确定 MCTS 大小、密度和细胞迁移。通过 Resazurin 和酸性磷酸酶测定评估细胞活力，通过 caspase 活性的荧光测定评估细胞凋亡。通过活/死荧光染色显示活细胞在 MCTS 内的分布。用 αMG 处理 MDA-MB-231 球体 48 h 后，获得细胞活力呈剂量依赖性下降（IC = 0.70-1.25 μg/ml）。仅在浓度为 30 μg/ml 时观察到球体体积显著减小，同时其紧凑度增加，但较低剂量的 αMG 则不然。相比之下，αMG 在 5-15 μg/ml 的范围内通过平行减少细胞聚集来增加 MCTS 的大小。相同的浓度窗口也能够以剂量依赖性方式刺激细胞凋亡。用 0.1÷30 μg/ml αMG 处理 MCF-7 细胞生成的球体 48 h 后，也获得了双模态体积效应。最后，高于 5 μg/ml 的剂量会导致 MDA-MB-231 MCTS 边缘的细胞迁移逐渐受损。在用 αMG 处理后，仅在 IC 以上的剂量下，MDA-MB-231 球体的细胞粘附显著降低，这不会刺激细胞迁移，但相反，会削弱细胞迁移。这些发现表明 αMG 具有新的抗癌特性，可考虑用于改善常规药物渗透到肿瘤块中。
