DR5介导的载多烯紫杉醇靶向脂质微泡联合超声靶向微泡破裂对人肝癌HepG2细胞凋亡及增殖的影响

目的 探讨DR5介导的载多烯紫杉醇靶向脂质微泡联合超声靶向微泡破裂技术对人肝癌HepG2细胞凋亡以及Bcl-2、NF-κB、Caspase-8、DR5蛋白表达的影响。方法 体外培养HepG2细胞并分为9组：空白对照组（Con），药物组（Drug），药物联合超声组（Drug+US），空白微泡组（MBs），空白微泡联合超声组（MBs+US），载药微泡组（DLLM），载药微泡联合超声组（DLLM+US），DR5介导的靶向载药微泡组（DR5-DLLM），DR5介导的靶向载药微泡联合超声组（DR5-DLLM+US）。Drug、Drug+US、DLLM、DLLM+US、DR5-DLLM、DR5-DLLM+US组中的多烯紫杉醇以IC50的药物浓度（5 nmol/L）给药，Con组加入0.5 mL生理盐水，超声以0.5 W/cm2的声强辐照45s，分组处理后，继续培养细胞24 h，分别用CCK-8、TUNEL、流式细胞术检测各组细胞增殖、细胞凋亡和细胞周期，并检测Bcl-2、NF-κB、Caspase-8、DR5的mRNA和蛋白表达水平。结果 与其他组相比，DR5介导的靶向载药微泡联合超声组对HepG2细胞的增殖抑制作用、凋亡诱导作用和G2/M细胞周期阻滞作用更强（P<0.001），且该组的Bcl-2 和 NF-κB mRNA 和蛋白表达水平明显降低（P<0.001），而 DR5 和 Caspase-8 的 mRNA 和蛋白表达水平明显升高（P< 0.001）。结论 DR5介导的载多烯紫杉醇靶向脂质微泡联合超声靶向微泡破裂技术可通过下调Bcl-2和NF-κB表达、上调Caspase-8和DR5表达，从而增强对人肝癌HepG2细胞周期阻滞、细胞增殖抑制和细胞凋亡诱导作用，因此有望成为一种新型、有效的肝癌超声靶向治疗方法。

Effect of DR5-mediated docetaxel-loaded lipid microbubble combined with ultrasound-targeted microbubble destruction on HepG2 cell proliferation and apoptosis

Objective To investigate the effect of DR5-mediated docetaxel-targeted lipid microbubbles (MBs) combined with ultrasound-targeted microbubble destruction on apoptosis and expressions of Bcl-2, nuclear factor-κB (NF-κB), caspase-8, and DR5 in human HepG2 cells. Methods HepG2 cells were treated with docetaxel at its 50% inhibitory concentration (IC50) of 5 nmol/L, docetaxel combined with ultrasound, blank MBs, blank MBs combined with ultrasound (0.5 W/cm2 for 45 s), drug-loaded lipid MBs (DLLM), DLLM combined with ultrasound, DR5-mediated DLLM (DR5-DLLM), or DR5-DLLM combined with ultrasound. After the treatments, the cells were further cultured for 24 h, and CCK-8 assay, TUNEL staining and flow cytometry were used to assess cell proliferation, apoptosis, and cell cycle changes; the changes in mRNA and protein expression levels of Bcl-2, NF-κB, caspase-8, and DR5 were detected with RT-qPCR and Western blotting. Results Among all the treatments, DR5-DLLM combined with ultrasound produced the strongest effects to inhibit the proliferation (P<0.001), promote apoptosis (P<0.001), and cause G2/M cell cycle arrest (P<0.001) in HepG2 cells. The combined treatment with DR5-DLLM and ultrasound also significantly downregulated Bcl-2 and NF-κB (P<0.001) and upregulated DR5 and caspase-8 expressions (P<0.001) at both the mRNA and protein levels. Conclusion DR5-DLLM combined with ultrasound-targeted microbubble destruction can induce G2/M cell cycle arrest, proliferation inhibition and apoptosis in HepG2 cells by downregulating Bcl-2 and NF-κB and upregulating DR5 and caspase-8 expressions, indicating its value as a novel ultrasound-targeted therapy for liver cancer.