矢车菊素-3-O-葡萄糖苷(C3G)通过靶向TOPK抑制结直肠癌细胞的增殖

Cyanidin-3-O-glucoside inhibits proliferation of colorectal cancer cells by targeting TOPK

目的研究矢车菊素-3-O-葡萄糖苷(C3G)对结直肠癌增殖的影响及机制。方法采用体外结合及体外激酶实验检测C3G与T细胞淋巴因子活化杀伤细胞来源的蛋白激酶(TOPK)的结合能力及对其活性的影响;采用软琼脂试验检测C3G对结肠癌细胞克隆形成能力的影响;采用MTS法测定C3G的细胞毒性;采用大肠杆菌BL21表达GST-组蛋白H3融合蛋白;采用慢病毒感染的方法,检测C3G对沉默TOPK的结肠癌细胞克隆形成能力的影响;Western blot法检测HCT116细胞中C3G对TOPK下游分子组蛋白H3的磷酸化的水平;建立结肠癌患者癌组织异种移植小鼠模型,免疫组织化学染色法检测组蛋白H3的磷酸化水平。结果C3G在体外直接与TOPK结合并抑制TOPK活性;C3G以浓度依赖的方式抑制结肠癌细胞的增殖及克隆形成;沉默TOPK降低结肠癌细胞对C3G的敏感性;C3G以时间和浓度依赖的方式抑制TOPK下游分子组蛋白H3的磷酸化水平;另外,C3G抑制患者来源的结肠癌组织异种移植瘤小鼠体内肿瘤的生长。结论C3G通过靶向TOPK抑制结直肠癌的生长。

Objective To explore the influence of cyanidin-3-O-glucoside(C3G) on the proliferation of colorectal cancer cells and its mechanism. Methods In vitro binding and in vitro kinase assay were used to detect the binding ability of C3G and T-LAK cell-originated protein kinase(TOPK) and its effect on TOPK activity. Soft AGAR test was used to detect the effect of C3G on the clonal ability of colon cancer cells. The cytotoxicity of C3G was determined by MTS assay. E. coli BL21 was used to express GST-histone H3 fusion protein. The effect of C3G on the clonogenesis of colon cancer cells with silenced TOPK was examined by lentivirus infection. The phosphorylation of histone H3 by C3G in HCT116 cells was determined by Western blotting. A mouse model of xenograft was established to study the phosphorylation level of histone H3 by immunohistochemical staining. Results C3G was directly bound to TOPK in vitro and inhibited TOPK activity. C3G inhibited the proliferation and clone formation of colon cancer cells in a concentration-dependent manner. Silencing TOPK decreased the sensitivity of colon cancer cells to C3G. C3G inhibited the phosphorylation of histone H3 downstream of TOPK in a time-and concentration-dependent manner. In addition, C3G inhibited tumor growth in mice with xenograft tumors from colon cancer tissues of a patient. Conclusion C3G can inhibit colorectal cancer growth by targeting TOPK.