HSP60 overexpression increases the protein levels of the p110α subunit of phosphoinositide 3‐kinase and c‐Myc

Heat shock protein 60 (HSP60) is a chaperone protein which plays an essential role in facilitating the folding of many newly synthesized proteins to reach their native forms. Increased HSP60 expression is observed in various types of human cancers. However, proteins induced by HSP60 to mediate transformation remain largely unknown. Here we show that HSP60 overexpression increases the protein levels of the p110α subunit of phosphoinositide 3‐kinase (PI3K). The amino acid domain 288‐383 of HSP60 is used to increase the protein levels. Overexpression of HSP60 also induces the levels of phosphorylated Akt. In addition, the amino acid domain 288‐383 of HSP60 is used to induce c‐Myc expression. Finally, a mono‐ubiquitinated form of β‐catenin has a higher activity to activate β‐catenin downstream targets compared to wild‐type β‐catenin. These results indicate that HSP60 overexpression induces the levels or activity of multiple oncogenic proteins to mediate transformation.     

纳米血小板递送miR-145靶向Myc抑制食管癌细胞增殖、迁移

目的体外实验研究构建纳米血小板加载miR-145的载药递送系统对食管癌细胞增殖、迁移的影响,并探讨其作用机制。方法超声法制备纳米血小板并用化学方法偶联miR-145获得载药递送系统,将实验分为4组:NP-miR-145组、P-miR-145组、miR-145组和空白对照组,通过细胞划痕、噻唑蓝(MTT)增殖实验和流式细胞术分别检测四组细胞迁移、增殖和凋亡能力,用RT-PCR检测miR-145的表达,Western blot法检测癌相关蛋白Myc的表达水平。结果细胞的迁移、增殖:NP-miR-145组Myc的表达,增加了食管癌细胞的凋亡率。结论纳米血小板可作为miR-145的优良递送载体有效地抑制食管癌细胞增殖、迁移,其作用可能是miR-145通过抑制癌相关蛋白Myc而实现。