PDF(Pubmed)
Abstract：
The cytotoxicity of the ethyl acetate fraction of the Calotropis gigantea (L.) Dryand. (C. gigantea) stem bark extract (CGEtOAc) has been demonstrated in many types of cancers. This study examined the improved cancer therapeutic activity of sorafenib when combined with CGEtOAc in HepG2 cells. The cell viability and cell migration assays were applied in HepG2 cells treated with varying concentrations of CGEtOAc, sorafenib, and their combination. Flow cytometry was used to determine apoptosis, which corresponded with a decline in mitochondrial membrane potential and activation of DNA fragmentation. Reactive oxygen species (ROS) levels were assessed in combination with the expression of the phosphatidylinositol-3-kinase (PI3K)/ protein kinase B (Akt)/ mammalian target of rapamycin (mTOR) pathway, which was suggested for association with ROS-induced apoptosis. Combining CGEtOAc at 400 μg/mL with sorafenib at 4 μM, which were their respective half-IC50 concentrations, significantly inhibited HepG2 viability upon 24 h of exposure in comparison with the vehicle and each single treatment. Consequently, CGEtOAc when combined with sorafenib significantly diminished HepG2 migration and induced apoptosis through a mitochondrial-correlation mechanism. ROS production was speculated to be the primary mechanism of stimulating apoptosis in HepG2 cells after exposure to a combination of CGEtOAc and sorafenib, in association with PI3K/Akt/mTOR pathway suppression. Our results present valuable knowledge to support the development of anticancer regimens derived from the CGEtOAc with the chemotherapeutic agent sorafenib, both of which were administered at half-IC50, which may minimize the toxic implications of cancer treatments while improving the therapeutic effectiveness toward future medical applications.
摘要：
Calotropisgigantea的乙酸乙酯级分的细胞毒性（L.)干旱区。(C.gigantea）茎皮提取物（CGEtOAc）已在许多类型的癌症中得到证明。这项研究检查了索拉非尼在HepG2细胞中与CGEtOAc组合时改善的癌症治疗活性。在用不同浓度的CGEtOAc处理的HepG2细胞中应用细胞活力和细胞迁移测定,索拉非尼,和他们的组合。流式细胞术用于确定细胞凋亡，这与线粒体膜电位的下降和DNA片段的激活相对应。结合磷脂酰肌醇-3-激酶（PI3K）/蛋白激酶B（Akt）/哺乳动物雷帕霉素靶蛋白（mTOR）途径的表达评估活性氧（ROS）水平，这被认为与ROS诱导的细胞凋亡有关。将400μg/mL的CGEtOAc与4μM的索拉非尼混合，它们各自的半IC50浓度，与媒介物和每种单一处理相比,在暴露24小时后显著抑制HepG2活力。因此,CGEtOAc与索拉非尼联合时通过线粒体相关机制显著减少HepG2迁移并诱导细胞凋亡。ROS的产生推测是暴露于CGEtOAc和索拉非尼的组合后刺激HepG2细胞凋亡的主要机制。与PI3K/Akt/mTOR通路抑制相关。我们的结果提供了有价值的知识，以支持从CGEtOAc与化学治疗剂索拉非尼衍生的抗癌方案的发展，两种药物均以IC50的一半给药,这可能会使癌症治疗的毒性最小化,同时提高未来医学应用的治疗效果.
