【作者】 罗淑敏；

【导师】 蔡继业；

【作者基本信息】 暨南大学 ， 有机化学， 2011， 硕士

【摘要】 化学药物治疗是目前国际上临床恶性肿瘤治疗的主要手段之一,但由于肿瘤细胞的耐药性使得化疗治疗没有达到预期的临床效果,提高肿瘤对化疗药物的敏感性成为恶性肿瘤治疗的关键。新兴起的靶向治疗前景很广,该方法基于基因或者受体的表达来选择用药,选择性强,所以疗效更好,而毒性更低,但目前还处于起步阶段,虽然它很有潜力,但并不能代替手术、化疗和放疗等传统的肿瘤治疗方法。为了提高癌细胞对化疗药物的敏感性,探索新型Hsp90抑制剂SNX-2112抗肿瘤的作用机制,本研究以人乳腺癌细胞MDA-MB-231、MCF-7、MCF-7/ADR为模型,采用原子力显微术、共聚焦显微术、MTT法、Annexin-v/PI荧光染色法、流式细胞技术和Western Blot等方法,对药物改变癌细胞的表面结构和相关蛋白进行检测,获得了以下具有创新性的成果：1、低浓度的联合用药作用乳腺癌细胞24小时,细胞膜表面结构被破坏,产生孔洞；作用48小时细胞被严重破坏使细胞周期在S期比例增加到51.7%±0.30%。联合用药通过改变细胞膜的结构对癌细胞进行有效杀伤,使得顺铂对癌细胞作用的IC50值由26.33μmol/L降低到13.32μmol/L,提高了癌细胞对抗癌药物的敏感性,抑制肿瘤细胞生长。2、新型Hsp90抑制剂SNX-2112能有效的抑制MCF-7/ADR细胞的生长,10μmol/L的SNX-2112作用MCF-7/ADR细胞48小时的抑制率为(63.6±8.2)%,凋亡率为(53.4±7.3)%。SNX-2112抑制Hsp90的活性,诱导Hsp90受体蛋白降解,影响细胞对DNA修复酶PARP的正常表达,诱导乳腺癌细胞凋亡,且耐药株并没有通过P-gp糖蛋白对SNX-2112发生耐药作用,降低SNX-2112的药效。采用原子力显微术探测细胞的形貌和表面结构的变化,结合生物技术手段对药物作用癌细胞进行细胞毒性、相关蛋白的检测,可以直观的看到药物对细胞的作用效果。联合用药提高癌细胞对化疗药物的敏感性,减少耐药性发生。新型Hsp90抑制剂SNX-2112诱导癌细胞凋亡,表现出良好的靶向作用效果,为抗癌药物的研究提供新的实验依据。更多还原

【Abstract】 Chemotherapy is a primary mean of clinical cancer treatment at pressent. However, due to drug resistance of tumor cells, chemotherapy was not able to reach the desirably clinical effect. So improved tumor sensitivity to chemotherapeutic drugs was a key problem to cancer treatment. Recently, the new method of targeted therapy is based on the expression of genes or receptor to selective drugs, so the efficacy will be better and toxicity will be lower. Targeted therapy application was at primary stage now. Although it has potential prospects, but can not replace surgery、chemotherapy、radiotherapy treatment and other traditional treatment for cancer at present.In order to improve the sensitivity of cancer cells to chemotherapeutic drugs, and explore anti-tumor mechanism of the novel Hsp90 inhibitor SNX-2112, human breast cancer cells:MDA-MB-231、MCF-7 and MCF-7/ADR were selected as models in this study. Atomic force microscopy、confocal microscopy、MTT method、Annexin-v/PI fluorescence staining、flow cytometry and Western Blot methods were used to detect changes in the surface structure of cancer cells and drug-related protein, and the following results were obtained:1、The surface structure of tumor cells were damaged when treated with tetrandrine in low concentration at 24h and 48h. The S phase of cell cycle percentage was increased from 30.5%±0.30% to 51.7%±0.30%. Combination therapy is a way to reduce the concentration of cisplatin IC50 reduced from 26.33μmol/L to 13.32μmol/L. It was able to improve the sensitivity of tumors to chemotherapeutic drugs treatment, inhibit tumor growth.2、A novel Hsp90 inhibitor SNX-2112 can effectively inhibit the growth of MCF-7/ADR cells and the activity of receptor protein. MCF-7/ADR cell was treated with 10μmol/L SNX-2112 for 48 hours. The inhibition rate was (63.6±8.2)%, and apoptotic rate was (53.4±7.3)%. SNX-2112 can induce degradation in Hsp90 and apoptosis in breast cancer cells. It changed the normal expression of DNA repair enzyme PARP of cancer cell. The drug resistant effect of SNX-2112 is not effected by the glycoprotein expression. Atomic force microscopy and other biotechnology tools were used to detect the changes in the surface structure and morphology、toxicity and drug-related protein of tumor cells. We can see the effect of drugs on cells in visualization. Combination treatment was able to improve the sensitivity of cancer cells, and reduce the occurrence of drug resistance. SNX-2112 is a good effect of targeted therapy drugs, and is able to induce apoptosis in cancer cells. This study provides a new experimental reference for anti-cancer drug research.更多还原