高强度聚焦超声对人膀胱癌细胞的生长抑制作用及机理研究

研究高强度聚焦超声（high intensity focused ultrasound,HIFU）对人膀胱癌细胞的杀伤作用,并探索其作用机理.用不同强度的HIFU处理人膀胱癌细胞T24,用台盼蓝排斥法染色、细胞增殖试验（MTT法）研究HIFU对癌细胞的杀伤和生长抑制作用;流式细胞术检测其对癌细胞周期、凋亡及相关基因表达的影响.HIFU处理后,癌细胞死亡率升高,增殖活性降低,G0/G1期细胞数增加,S期细胞数减少,凋亡指数升高,与对照组比较,差异有显著性意义（P＜0.05）;P53、BCL-2和FAS表达阳性细胞数与对照组比较,无显著性意义（P＞0.05）;HIFU强度为600 W/cm^2时,HSP70表达阳性细胞数升高,与对照组比较差异有显著性意义（P＜0.05）.HIFU对人膀胱癌细胞T24具有明显的杀伤及抑制作用,其机理与抑制DNA合成有关;HIFU具有诱导癌细胞凋亡的作用,其诱导凋亡作用可能与P53、BCL-2和FAS无关.

Mechanism Study on the Inhibitive Effect of High Intensity Focused Ultrasound on Proliferation of Human Bladder Cancer Cells

The killing effect of high intensity focused ultrasound(HIFU) on hu ma n bladder cancer cells and its mechanism was studied.Human bladder cancer cells( T24) were treated with different intensity of HIFU in vitro and incubated.The ki lling effect and proliferation inhibition effect of HIFU on tumor cells were inv estigated with trypan blue exclusion assay and MTT assay.The cell cycle,apoptoti c cells and the expression of P53,BCL-2,FAS and HSP70 were measured with flow c ytometry.After HIFU treatment,the death rates of cancer cells increased,and the proliferation rate decreased.The cell number increased in G0/G1 phase,decreased in S phase with the increased apoptotic indices.Comparing with the control,diffe rence was significant(P<0.05).When intensity of HIFU was 600 W/cm2,the express ion of HSP70 was enhanced(P<0.05) and there were no significant changes of P53,B CL-2 and FAS expression(P>0.05).HIFU has significant effects such as killing,proliferation inhibition on human bladder cancer cells.Its mec hanisms of action may be associated with the inhibition of DNA synthesis.In addi tion,HIFU can induce apoptotic cell death,which may not be associated with the m ediation and regulation of P53,BCL-2 and FAS genes.