LncRNA PVT1 promotes gemcitabine resistance of pancreatic cancer via activating Wnt/β-catenin and autophagy pathway through modulating the miR-619-5p/Pygo2 and miR-619-5p/ATG14 axes
LncRNA PVT1 promotes gemcitabine resistance of pancreatic cancer via activating Wnt/β-catenin and autophagy pathway through modulating the miR-619-5p/Pygo2 and miR-619-5p/ATG14 axes
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LncRNA PVT1 通过调节 miR-619-5p/Pygo2 和 miR-619-5p/ATG14 轴激活 Wnt/β-catenin 和自噬途径促进胰腺癌吉西他滨耐药
DOI：
10.1186/s12943-020-01237-y
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发表时间：
2020-07-29
期刊：
影响因子：
37.3
通讯作者：
Tang, Jingfeng
中科院分区：
文献类型：
--
作者：
Zhou, Cefan;Yi, Changhua;Tang, Jingfeng
背景：胰腺癌是最致命的恶性肿瘤之一，诊断和预后极差。吉西他滨耐药性的发展仍然是一个重大挑战。据报道，长的非编码RNA PVT 1参与致癌和化疗耐药性，然而，机制PVT 1调节胰腺癌的敏感性吉西他滨仍然知之甚少。方法：胰腺癌细胞的生存能力进行了评估，MTT法在体外和异种移植瘤形成试验在体内。采用实时荧光定量PCR（qRT-PCR）检测PVT 1和miR-619- 5 p的表达水平。进行蛋白质印迹分析和qRT-PCR以分别评估Pygo 2和ATG 14的蛋白质和mRNA水平。自噬通过共聚焦显微镜下的自噬通量检测和透射电子显微镜下的自噬空泡研究来探索。PVT 1的功能作用和机制进行了进一步研究，通过获得和丧失的功能assaysinvitro.Results：在本研究中，我们证明，PVT 1在吉西他滨耐药的胰腺癌细胞系上调。功能获得和丧失试验显示，PVT 1在体外和体内损害对吉西他滨的敏感性。我们进一步发现，PVT 1上调Pygo 2和ATG 14的表达，从而调节Wnt/β-连环蛋白信号传导和自噬活性，以通过海绵状miR-619- 5 p克服吉西他滨耐药性。此外，我们在PVT 1的启动子区发现了三个TCF/LEF结合元件（TBE），并且通过Pygo 2的上调介导的Wnt/β-连环蛋白信号传导的激活通过直接结合到TBE区来增加PVT 1的表达。此外，发现PVT 1与ATG 14相互作用，从而促进自噬特异性复合物I（PtdIns 3 K-C1）和ATG 14依赖性III类PtdIns 3 K activity.Conclusions的组装：这些数据表明，PVT 1在胰腺癌对吉西他滨的敏感性中起着关键作用，并突出了其作为胰腺癌治疗有价值的靶点的潜力。
Background: Pancreatic cancer is one of the most lethal malignancies and has an extremely poor diagnosis and prognosis. The development of resistance to gemcitabine is still a major challenge. The long noncoding RNA PVT1 was reported to be involved in carcinogenesis and chemoresistance; however, the mechanism by which PVT1 regulates the sensitivity of pancreatic cancer to gemcitabine remains poorly understood.Methods: The viability of pancreatic cancer cells was assessed by MTT assay in vitro and xenograft tumor formation assay in vivo. The expression levels of PVT1 and miR-619-5p were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Western blotting analysis and qRT-PCR were performed to assess the protein and mRNA levels of Pygo2 and ATG14, respectively. Autophagy was explored via autophagic flux detection under confocal microscopy and autophagic vacuole investigation under transmission electron microscopy (TEM). The functional role and mechanism of PVT1 were further investigated by gain- and loss-of-function assays in vitro.Results: In the present study, we demonstrated that PVT1 was up-regulated in gemcitabine-resistant pancreatic cancer cell lines. Gain- and loss-of-function assays revealed that PVT1 impaired sensitivity to gemcitabine in vitro and in vivo. We further found that PVT1 up-regulated the expression of both Pygo2 and ATG14 and thus regulated Wnt/beta-catenin signaling and autophagic activity to overcome gemcitabine resistance through sponging miR-619-5p. Moreover, we discovered three TCF/LEF binding elements (TBEs) in the promoter region of PVT1, and activation of Wnt/beta-catenin signaling mediated by the up-regulation of Pygo2 increased PVT1 expression by direct binding to the TBE region. Furthermore, PVT1 was discovered to interact with ATG14, thus promoting assembly of the autophagy specific complex I (PtdIns3K-C1) and ATG14-dependent class III PtdIns3K activity.Conclusions: These data indicate that PVT1 plays a critical role in the sensitivity of pancreatic cancer to gemcitabine and highlight its potential as a valuable target for pancreatic cancer therapy.