高强度聚焦超声波通过调控miR-1297/PTEN分子轴抑制胰腺癌细胞的增殖与迁移

High intensity focused ultrasound inhibits the proliferation and migration of pancreatic cancer cells via regulating miR-1297/PTEN axis

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,mi R-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.