Kim Young-Kyun, Koo Na-Youn, Yun Pil-Young
Department of Oral and Maxillofacial Surgery, Section of Dentistry, Seoul National University Bundang Hospital, Seongnam-si, Gyeonggi-do 463-707, Republic of Korea.
Oncol Lett. 2015 Jan;9(1):136-142. doi: 10.3892/ol.2014.2648. Epub 2014 Oct 30.
CKD-602 (7-[2-(N-isopropylamino) ethyl]-(20S)-camptothecin, belotecan) is a synthetic water-soluble camptothecin derivative and topoisomerase I inhibitor that has been shown to exert a clinical anticancer effect on various types of tumor. In the present study, the anticancer effects of CKD-602 on the following three human oral squamous cell carcinoma (OSCC) cell lines originating from Korean cancer patients: YD-8 (tongue), YD-9 (buccal mucosa) and YD-38 (lower gingiva) were analyzed. The apoptotic proportion of the cells and cell cycle position were analyzed using flow cytometry. The expression of cell cycle regulatory proteins was detected by western blot analysis. CKD-602 was demonstrated to exert a time- and dose-dependent antiproliferative effect in all cell lines , however, susceptibility to CKD-602 at 72 h following treatment varied among the three cell lines, with 50% inhibition of cell viability at concentrations of 2.4 μg/ml for YD-8, 0.18 μg/ml for YD-9 and 0.05 μg/ml for YD-38. To investigate the underlying mechanism of the CKD-602 antiproliferative effect, a cell cycle-analysis was conducted in the three OSCC cell lines and CKD-602 treatment was observed to induce G2/M phase arrest. Furthermore, western blot analysis revealed that the expression levels of phospho-cdc2 (Tyr 15), cyclin A2 and cyclin B1 were increased in a time-dependent manner, following the administration of CKD-602. In the fluorescence-activated cell sorting analysis, the number of apoptotic cells was also increased in a dose-dependent manner following CKD-602 treatment of the OSCC cell lines. The results suggest that CKD-602 may inhibit the proliferation of OSCC oral cancer cells derived from samples from Korean patients by apoptosis and by G2/M phase arrest.
CKD-602（7-[2-(N-异丙基氨基)乙基]-(20S)-喜树碱，倍喜）是一种合成的水溶性喜树碱衍生物和拓扑异构酶I抑制剂，已被证明对多种类型的肿瘤具有临床抗癌作用。在本研究中，分析了CKD-602对以下三种源自韩国癌症患者的人口腔鳞状细胞癌（OSCC）细胞系的抗癌作用：YD-8（舌）、YD-9（颊黏膜）和YD-38（下牙龈）。使用流式细胞术分析细胞的凋亡比例和细胞周期位置。通过蛋白质印迹分析检测细胞周期调节蛋白的表达。结果表明，CKD-602在所有细胞系中均表现出时间和剂量依赖性的抗增殖作用，然而，三种细胞系在处理后72小时对CKD-602的敏感性各不相同，YD-8在浓度为2.4μg/ml时细胞活力受到50%抑制，YD-9为0.18μg/ml，YD-38为0.05μg/ml。为了研究CKD-602抗增殖作用的潜在机制，对三种OSCC细胞系进行了细胞周期分析，观察到CKD-602处理可诱导G2/M期阻滞。此外，蛋白质印迹分析显示，给予CKD-602后，磷酸化cdc2（Tyr 15）、细胞周期蛋白A2和细胞周期蛋白B1的表达水平呈时间依赖性增加。在荧光激活细胞分选分析中，CKD-602处理OSCC细胞系后，凋亡细胞数量也呈剂量依赖性增加。结果表明，CKD-602可能通过凋亡和G2/M期阻滞抑制源自韩国患者样本的OSCC口腔癌细胞的增殖。
