Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of Alabama at Birmingham, Birmingham, Alabama, USA.
Laryngoscope. 2011 Nov;121(11):2359-65. doi: 10.1002/lary.22180.
OBJECTIVES/HYPOTHESIS: MK-2206 is an orally active, allosteric inhibitor of AKT, a component of the phosphatidylinositol-3 kinase (PI3K) pathway. The PI3K-AKT pathway is a downstream signaling pathway that has recently been found to play an important role in head and neck squamous cell carcinoma (HNSCC). The objective of this study is to examine the role AKT inhibition may play in treatment of HNSCC.
In vivo and in vitro study.
Cell migration after 24-hour treatment with subtherapeutic doses of MK-2206 was assessed using an enzyme-linked immunosorbent assay in four HNSCC cell lines: CAL27, FaDu, SCC-1, and SCC-5. In vitro effect of MK-2206 on cell migration was assessed by making linear scratches in culture plates after cell lines were grown to confluency. Images were taken at 8, 16, and 24 hours. In vivo analysis was performed on nude mice with human SCC1-orthotopic tongue tumors. After tumors were allowed to grow for 7 days, mice were treated with oral dosing of 120 mg/kg of MK-2206 every other day for 2 weeks. Tumor size was assessed after each treatment using a pair of digital calipers. At the end of the treatment period, mice were sacrificed and cervical lymph nodes were assessed for metastasis using fluorescent imaging of tumor cell markers.
Subtherapeutic doses of MK-2206 were sufficient to significantly reduce cell migration in FaDu, SCC-1, and SCC-5 cell lines (P < .001) but not in Cal27 (P = .09). In vitro scratch test results in SCC-1 cells yielded significant reduction in cell movement at 8, 16, and 14 hours (P < .001). In vivo orthotopic model yielded significant reduction in primary tumor size (P = .04) and reduction in positive cervical lymph nodes (P = .01) between treatment and control mice. In addition we found 100% survival of MK-2206 treated mice after 2 weeks of treatment compared with 70% survival in our control group (P = .03).
Treatment with MK-2206 is sufficient to inhibit HNSCC chemotaxis and migration in vitro. In an orthotopic model, treatment with MK-2206 reduces primary tumor size and cervical metastasis while improving survival. MK-2206 currently is being used in phase II clinical trials for combination treatment of metastatic solid tumors and may be useful for treating HNSCC as well.
目的/假设：MK-2206 是一种口服活性、变构 AKT 抑制剂，AKT 是磷脂酰肌醇 3-激酶（PI3K）途径的一个组成部分。PI3K-AKT 途径是一个下游信号通路，最近被发现其在头颈部鳞状细胞癌（HNSCC）中发挥着重要作用。本研究的目的是研究 AKT 抑制在 HNSCC 治疗中的可能作用。
体内和体外研究。
使用酶联免疫吸附试验在 4 种 HNSCC 细胞系（CAL27、FaDu、SCC-1 和 SCC-5）中评估亚治疗剂量的 MK-2206 处理 24 小时后细胞的迁移。通过在细胞系达到汇合后在培养板上制作线性划痕来评估 MK-2206 对细胞迁移的体外作用。在 8、16 和 24 小时时拍摄图像。在携带人 SCC1-原位舌肿瘤的裸鼠中进行体内分析。在允许肿瘤生长 7 天后，每天用 120mg/kg 的 MK-2206 进行口服治疗，共 2 周。每次治疗后使用一对数字卡尺评估肿瘤大小。在治疗期结束时，处死小鼠，并使用肿瘤细胞标志物的荧光成像评估颈部淋巴结转移。
亚治疗剂量的 MK-2206 足以显著降低 FaDu、SCC-1 和 SCC-5 细胞系中的细胞迁移（P<0.001），但对 Cal27 没有影响（P=0.09）。SCC-1 细胞的体外划痕试验结果显示，细胞运动在 8、16 和 14 小时显著减少（P<0.001）。体内原位模型显示，MK-2206 治疗组与对照组相比，原发性肿瘤大小显著减小（P=0.04），阳性颈部淋巴结减少（P=0.01）。此外，我们发现，与对照组的 70%存活率相比，MK-2206 治疗组的 2 周治疗后 100%的小鼠存活（P=0.03）。
MK-2206 治疗足以抑制体外 HNSCC 趋化性和迁移。在原位模型中，MK-2206 治疗可降低原发性肿瘤大小和颈部转移，同时提高存活率。MK-2206 目前正在进行转移性实体瘤联合治疗的 II 期临床试验，对 HNSCC 也可能有用。
