Department of Neurosurgery, St. Vincent's Hospital, Cell Death Disease Research Center, College of Medicine, The Catholic University of Korea, Suwon, Korea.
Division of Nephrology, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Cancer Res Treat. 2018 Oct;50(4):1331-1342. doi: 10.4143/crt.2017.466. Epub 2018 Jan 10.
The purpose of the study is to investigate the efficacy of combined treatment with temozolomide (TMZ) and metformin for glioblastoma (GBM) in vitro and in vivo.
We investigated the efficacy of combined treatment with TMZ and metformin using cell viability and apoptosis assays. A GBM orthotopic mice model was established by inoculation of 5×105 U87 cells and treatedwith metformin, TMZ, and the combination for 4weeks. Western blotting and immunofluorescence of tumor specimens were analyzed to investigate AMP-activated protein kinase (AMPK) and AKT pathway.
The combination of TMZ and metformin showed higher cytotoxicity than single agents in U87, U251, and A172 cell lines. A combination of high-dose metformin and TMZ showed the highest apoptotic activity. The combination of TMZ and metformin enhanced AMPK phosphorylation and inhibited mammalian target of rapamycin phosphorylation, AKT phosphorylation, and p53 expression. The median survival of each group was 43.6, 55.2, 53.2, 65.2, and 71.3 days for control, metformin treatment (2 mg/25 g/day or 10 mg/25 g/day), TMZ treatment (15 mg/kg/day), combination treatment with low-dose metformin and TMZ, and combination treatment with high-dose metformin and TMZ, respectively. Expression of fatty acid synthase (FASN) was significantly decreased in tumor specimens treated with metformin and TMZ.
The combination of metformin and TMZ was superior to monotherapy using metformin or TMZ in terms of cell viability in vitro and survival in vivo. The combination of high-dose metformin and TMZ inhibited FASN expression in an orthotopic model. Inhibition of FASN might be a potential therapeutic target of GBM.
本研究旨在探讨替莫唑胺（TMZ）联合二甲双胍治疗体外和体内胶质母细胞瘤（GBM）的疗效。
我们通过细胞活力和凋亡实验研究了 TMZ 联合二甲双胍治疗的疗效。通过接种 5×105 U87 细胞建立 GBM 原位小鼠模型，并接受二甲双胍、TMZ 和联合治疗 4 周。分析肿瘤标本的 Western blot 和免疫荧光，以研究 AMP 激活的蛋白激酶（AMPK）和 AKT 通路。
TMZ 联合二甲双胍在 U87、U251 和 A172 细胞系中的细胞毒性高于单药治疗。高剂量二甲双胍和 TMZ 的联合治疗显示出最高的凋亡活性。TMZ 联合二甲双胍增强了 AMPK 磷酸化，抑制了哺乳动物雷帕霉素靶蛋白磷酸化、AKT 磷酸化和 p53 表达。各组的中位生存时间分别为对照组 43.6、二甲双胍治疗组（2mg/25g/天或 10mg/25g/天）55.2、TMZ 治疗组 53.2、低剂量二甲双胍和 TMZ 联合治疗组 65.2 和高剂量二甲双胍和 TMZ 联合治疗组 71.3 天。二甲双胍和 TMZ 治疗的肿瘤标本中脂肪酸合酶（FASN）的表达明显降低。
与单独使用二甲双胍或 TMZ 相比，二甲双胍和 TMZ 的联合治疗在体外细胞活力和体内生存方面均具有优势。高剂量二甲双胍和 TMZ 的联合治疗抑制了原位模型中 FASN 的表达。抑制 FASN 可能是 GBM 的潜在治疗靶点。
