Coleman Sean C, Stewart Zoe A, Day Terry A, Netterville James L, Burkey Brian B, Pietenpol Jennifer A
Department of Biochemistry, Vanderbilt University School of Medicine, 652 The Preston Building, 2220 Pierce Ave, Nashville, TN 37232-6305, USA.
Arch Otolaryngol Head Neck Surg. 2002 Feb;128(2):167-76. doi: 10.1001/archotol.128.2.167.
To determine the mechanism of action of paclitaxel (Taxol) and carboplatin in cell lines of head and neck squamous cell carcinoma (HNSCC).
Four HNSCC cell lines were treated with paclitaxel and carboplatin, alone or in combination, and evaluated for cell-cycle position by means of flow cytometry, for molecular determinants of cell cycle by means of Western blotting and kinase analysis, and for anchorage-independent growth by means of soft-agar assays.
Paclitaxel was more effective at inducing apoptosis and inhibiting anchorage-independent cell growth, compared with carboplatin. The activity of paclitaxel was correlated with an elevation of cyclin B1/CDC2 activity, prolonged mitotic arrest, and Bcl-2 phosphorylation. In contrast, carboplatin arrested cells before mitosis. Combination treatment with both agents, simultaneously or sequentially, was more effective at inhibiting cell growth than either single agent. Cellular outcome was the same regardless of which drug was used first. The order of addition of these 2 drugs differentially affected cell-cycle position. Paclitaxel pretreatment arrested cells in mitosis, whereas carboplatin pretreatment or cotreatment resulted in premitotic arrest.
To our knowledge, this study is the first to explore how paclitaxel and carboplatin, alone or in combination, differentially affect cell-cycle checkpoint response and HNSCC cell growth. These results provide molecular validation for the current clinical use of both drugs in combination and set the stage for analyses of patient tumor specimens.
确定紫杉醇(泰素)和顺铂在头颈部鳞状细胞癌(HNSCC)细胞系中的作用机制。
用紫杉醇和顺铂单独或联合处理4种HNSCC细胞系,通过流式细胞术评估细胞周期位置,通过蛋白质印迹法和激酶分析评估细胞周期的分子决定因素,通过软琼脂试验评估非贴壁依赖性生长。
与顺铂相比,紫杉醇在诱导细胞凋亡和抑制非贴壁依赖性细胞生长方面更有效。紫杉醇的活性与细胞周期蛋白B1/细胞分裂周期蛋白2(Cyclin B1/CDC2)活性升高、有丝分裂延长停滞以及Bcl-2磷酸化相关。相比之下,顺铂在有丝分裂前使细胞停滞。两种药物同时或序贯联合治疗在抑制细胞生长方面比单一药物更有效。无论先用哪种药物,细胞结果相同。这两种药物添加的顺序对细胞周期位置有不同影响。紫杉醇预处理使细胞停滞在有丝分裂期,而顺铂预处理或联合处理导致有丝分裂前停滞。
据我们所知,本研究首次探讨了紫杉醇和顺铂单独或联合使用如何不同地影响细胞周期检查点反应和HNSCC细胞生长。这些结果为这两种药物联合使用的当前临床应用提供了分子验证,并为分析患者肿瘤标本奠定了基础。