目的：研究鬼臼毒素衍生物CIP-36对多药耐药人口腔鳞状上皮癌细胞KBV 200的抗肿瘤活性及其作用机制。方法：MTT法考察CIP-36对KBV 200体外增殖的抑制作用；Giemsa染色、DNA ladder和流式细胞仪等方法进行细胞凋亡检测；免疫荧光法观察CIP-36对细胞骨架的作用；western-blot法检测CIP-36对KBV 200细胞P-gp表达的影响。结果：CIP-36对KBV 200细胞有明显的抑制作用，IC₅₀值为（2.06±0.38）μmol / L，能够诱导细胞产生凋亡小体和DNA ladder。流式细胞检测到了细胞凋亡峰，并观察到细胞周期出现S/G₂+M期阻滞。Western-blot结果显示P-gp表达降低，并且观察到CIP-36可破坏KBV 200细胞的细胞骨架。结论：CIP-36可能通过降低P-gp的表达，破坏细胞骨架等多靶点克服KBV 200细胞株的多药耐药性。

Objective: To study the antitumor activity of CIP-36 on multidrug resistance human oral squamous carcinoma cells (KBV 200 cells) in vitro and the feasible anticancer mechanisms. Methods: MTT assay, morphological study, DNA gel electrophoresis, flow cytometry, western-blot, and immunofluorescence were carried out. Results: The IC₅₀ value of CIP-36 on KBV 200 cells was (2.06 ± 0.38) μmol / L. After treated with CIP-36, the apparent morphological characteristic and typical DNA ladder of KBV 200 cells were all detected. Both the number of apoptosis cells and the cell cycle were measured by flow cytometric; A typical “Sub-G₁ peak” was checked and CIP-36 blocked the cell cycle at S/G₂ + M phase. Western-blot showed that the expression of P-glycoprotein was decreased. CIP-36 could interfere with microtubule polymerization and disrupt cytoskeleton. Conclusions: CIP-36 has the potentiality to overcome P-glycoprotein- mediated multidrug resistance in the KBV 200 cell line.

国家自然科学基金（No 30873363）；天津市自然科学基金重点资助项目（No 08JCYBJC070000）；天津市自然科学重点支持项目（No 09ZCKFNC01200）