Axon Guidance Factor SLIT2 Inhibits Neural Invasion and Metastasis in Pancreatic Cancer
Axon Guidance Factor SLIT2 Inhibits Neural Invasion and Metastasis in Pancreatic Cancer
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DOI：
10.1158/0008-5472.can-13-1012
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发表时间：
2014-03-01
期刊：
影响因子：
11.2
通讯作者：
Fischer, Christian
中科院分区：
文献类型：
--
作者：
Goehrig, Andreas;Detjen, Katharina M.;Fischer, Christian
胰腺导管腺癌（PDAC）通过神经、血管和局部浸润途径转移，这限制了患者的生存。在神经和血管中，SLIT 2及其ROBO受体构成了也指导上皮分支的驱避剂引导线索。因此，SLIT 2-ROBO系统可以代表调节PDAC扩散的关键夹点。在这项研究中，我们研究了这样一种假设，即逃避排斥性SLIT 2-ROBO信号传导对于使PDAC细胞能够适当地利用其局部基质基础结构进行传播是必不可少的。通过免疫组织化学分析，我们检测SLIT 2受体ROBO 1和ROBO 4分别在正常胰腺和PDAC标本的上皮，神经和血管。与未转化的胰腺组织和细胞系相比，PDAC中SLIT 2 mRNA表达降低，表明PDAC中SLIT 2-ROBO通路活性降低。支持这种解释，恢复SLIT 2缺陷PDAC细胞中的SLIT 2表达抑制了它们与神经细胞的双向化学吸引，更具体地说，在神经侵袭模型中，受损的单向PDAC细胞沿着沿着长出的神经突导航。恢复自分泌/旁分泌SLIT 2信号传导也足以抑制PDAC细胞的定向运动，但不抑制其随机运动。相反，RNA干扰介导的ROBO 1沉默刺激SLIT 2-感受态PDAC细胞的运动性。此外，SLIT 2-感受态PDAC细胞的培养上清液损害了内皮细胞（人脐静脉内皮细胞）的迁移，而N-末端SLIT 2切割片段刺激了这种迁移。对SLIT 2表达恢复的胰腺肿瘤的体内研究表明，侵袭、转移和血管形成减少，而肿瘤细胞中的ROBO 1沉默或内源性SLIT 2的隔离产生了相反的效果。对PDAC临床标本的分析表明，SLIT 2 mRNA表达低的患者表现出较高的发病率和较高的肿瘤浸润淋巴结比例。综上所述，我们的研究结果表明，破坏PDAC中的SLIT 2-ROBO信号传导可能会增强转移并使PDAC细胞易于神经侵袭。(c)2014年AACR。
Pancreatic ductal adenocarcinoma (PDAC) metastasizes by neural, vascular, and local invasion routes, which limit patient survival. In nerves and vessels, SLIT2 and its ROBO receptors constitute repellent guidance cues that also direct epithelial branching. Thus, the SLIT2-ROBO system may represent a key pinch point to regulate PDAC spread. In this study, we examined the hypothesis that escaping from repellent SLIT2-ROBO signaling is essential to enable PDAC cells to appropriate their local stromal infrastructure for dissemination. Through immunohistochemical analysis, we detected SLIT2 receptors ROBO1 and ROBO4 on epithelia, nerves, and vessels in healthy pancreas and PDAC specimens, respectively. SLIT2 mRNA expression was reduced in PDAC compared with nontransformed pancreatic tissues and cell lines, suggesting a reduction in SLIT2-ROBO pathway activity in PDAC. In support of this interpretation, restoring the SLIT2 expression in SLIT2-deficient PDAC cells inhibited their bidirectional chemoattraction with neural cells, and more specifically, impaired unidirectional PDAC cell navigation along outgrowing neurites in models of neural invasion. Restoring autocrine/ paracrine SLIT2 signaling was also sufficient to inhibit the directed motility of PDAC cells, but not their random movement. Conversely, RNA interference-mediated silencing of ROBO1 stimulated the motility of SLIT2-competent PDAC cells. Furthermore, culture supernatants from SLIT2-competent PDAC cells impaired migration of endothelial cells (human umbilical vein endothelial cells), whereas an N-terminal SLIT2 cleavage fragment stimulated such migration. In vivo investigations of pancreatic tumors with restored SLIT2 expression demonstrated reduced invasion, metastasis, and vascularization, with opposing effects produced by ROBO1 silencing in tumor cells or sequestration of endogenous SLIT2. Analysis of clinical specimens of PDAC showed that those with low SLIT2 mRNA expression exhibited a higher incidence and a higher fraction of tumor-infiltrated lymph nodes. Taken together, our findings argue that disrupting SLIT2-ROBO signaling in PDAC may enhance metastasis and predispose PDAC cells to neural invasion. (c) 2014 AACR.