目的: 探讨高强度聚焦超声波（high intensity focused ultrasound，HIFU）通过miR-1297/PTEN分子轴抑制胰腺癌细胞增殖和迁移的作用机制。方法: HIFU 作用于体外培养的胰腺癌PANC-1 细胞1、2 和3 s，采用CCK-8 法、Transwell 小室法和Annexin V-FITC/PI 双染流式细胞术分别检测HIFU对PANC-1 细胞增殖、迁移和凋亡的影响；用qPCR和Western blotting 法分别检测HIFU 对PANC-1 细胞miR-1297 和PTEN表达的影响，用双荧光素酶报告基因验证miR-1297 与PTEN的靶向关系。通过转染miR-1297 inhibitor 和PTEN-siRNA，采用Western blotting 法检测HIFU对Akt 磷酸化的影响。结果: 随着HIFU作用时间的延长，对胰腺癌PANC-1 细胞增殖和迁移能力的抑制作用不断增强，并促进细胞凋亡（均P<0.01），抑制PANC-1细胞中miR-1297的表达和促进PTEN的表达（均P<0.05或P<0.01）；同时，miR-1297 靶向作用PTEN并下调其表达水平。HIFU显著抑制Akt 的磷酸化水平（P<0.05 或P<0.01）。结论: HIFU通过下调miR-1297抑制PTEN的表达并阻断Akt 信号通路，进而抑制胰腺癌发生发展的进程。

Objective: To explore the role and molecular mechanism of high intensity focused ultrasound (HIFU) inhibits pancreatic cancer cell proliferation and invasion via regulating miR-1297/PTEN axis. Methods: With treating the cells with HIFU for 1 to 3 seconds,the effect of HIFU on cell proliferation, invasion and apoptosis of PANC-1 cells in vitro was examined by CCK-8, Transwell and Annexin V-FITC/PI double staining flow cytometry, respectively. The effect of HIFU on expression of miR-1297 and PTEN were measured by qPCR and Western blotting. Moreover, the relationship between miR-1297 and PTEN was examined by dual luciferase report assay. Western blotting was used to detect the effect of HIFU on the expression of Akt, p-Akt (308) and p-Akt (473) after transfected with miR-1297 inhibitor and PTEN-siRNA. Results: HIFU treatment significantly inhibited the cell proliferation, invasion and promoted apoptosis of PANC-1 cells (all P<0.01), which was associated with inhibition of miR-1297 expression and activation of PTEN expression in pancreatic cancer cells (all P<0.01). Moreover, miR-1297 directly binds to the 3′ UTR of PTEN mRNA to suppress its expression in PANC-1 cells. Further, HIFU exposure could significantly inhibit the expression of the phosphorylation of Akt (P<0.01).Conclusion: HIFU inhibits PTEN and blocks Akt signaling by down-regulating miR-1297, thereby suppresses the occurrence and progress of pancreatic cancer.