Alpha-enolase (ENO1) controls alpha v/beta 3 integrin expression and regulates pancreatic cancer adhesion, invasion, and metastasis

Abstract

BackgroundWe have previously shown that in pancreatic ductal adenocarcinoma (PDA) cells, the glycolytic enzyme alpha-enolase (ENO1) also acts as a plasminogen receptor and promotes invasion and metastasis formation. Moreover, ENO1 silencing in PDA cells induces oxidative stress, senescence and profoundly modifies PDA cell metabolism. Although anti-ENO1 antibody inhibits PDA cell migration and invasion, little is known about the role of ENO1 in regulating cell-cell and cell-matrix contacts. We therefore investigated the effect of ENO1 silencing on the modulation of cell morphology, adhesion to matrix substrates, cell invasiveness, and metastatic ability.MethodsThe membrane and cytoskeleton modifications that occurred in ENO1-silenced (shENO1) PDA cells were investigated by a combination of confocal microscopy and atomic force microscopy (AFM). The effect of ENO1 silencing was then evaluated by phenotypic and functional experiments to identify the role of ENO1 in adhesion, migration, and invasion, as well as in senescence and apoptosis. The experimental results were then validated in a mouse model.ResultsWe observed a significant increase in the roughness of the cell membrane due to ENO1 silencing, a feature associated with an impaired ability to migrate and invade, along with a significant downregulation of proteins involved in cell-cell and cell-matrix adhesion, including alpha v/beta 3 integrin in shENO1 PDA cells. These changes impaired the ability of shENO1 cells to adhere to Collagen I and IV and Fibronectin and caused an increase in RGD-independent adhesion to vitronectin (VN) via urokinase plasminogen activator receptor (uPAR). Binding of uPAR to VN triggers integrin-mediated signals, which result in ERK1-2 and RAC activation, accumulation of ROS, and senescence. In shENO1 cancer cells, the use of an anti-uPAR antibody caused significant reduction of ROS production and senescence. Overall, a decrease of in vitro and in vivo cell migration and invasion of shENO1 PDA cells was observed.ConclusionThese data demonstrate that ENO1 promotes PDA survival, migration, and metastasis through cooperation with integrins and uPAR.Electronic supplementary materialThe online version of this article (doi:10.1186/s13045-016-0385-8) contains supplementary material, which is available to authorized users.

Cancer/testis antigen‐Plac1 promotes invasion and metastasis of breast cancer through Furin/NICD/PTEN signaling pathway

“…Our current functional studies indicate that Plac1 has an oncogenic role to promote tumor migration and invasion, which is consistent with the results from a previous study (Koslowski et al ., ). However, a prerequisite for promoting tumor cell invasion and metastasis is that individual cells break down cell–cell contacts and remodel cell–matrix adhesion sites (Principe et al ., ). Plac1 appears to be responsible for upregulating the expression of MMP2 and MMP9, which degrade the extracellular matrix to promote tumor cell invasion and metastasis.…”

Unlikely role of glycolytic enzyme ��-enolase in cancer metastasis and its potential as a prognostic biomarker

“…Overexpression of a-enolase has been shown to increase the migration and invasion of hepatocellular carcinoma, colorectal and gastric cancer cells in vitro [11,58,60,61,67] and to enhance colorectal cancer metastasis in vivo [11] , demonstrating that it is an important driver of metastasis in multiple cancer types [ Table 3]. Conversely, knockdown or pharmacological inhibition of a-enolase decreased the migration and invasion of glioma, colorectal, pancreatic and endometrial carcinoma in vitro [6,12,63,68,69] , and decreased tumourigenesis and metastasis of endometrial carcinoma in vivo [12] . Furthermore, binding of recombinant a-enolase to the surface of prostate cancer cells was shown to promote cell migration via its plasminogen receptor activity [70] .…”

“…Decreased expression reduced migration and invasion in vitro and metastasis in vivo [12] Gastric cancer Knockdown in AGS cells and overexpression in SGC7901 cells Knockdown decreased migration, and overexpression increased migration [60] Overexpression in AGS cells Overexpression increased migration [ antibody decreased invasion in vitro and in vivo [72] Pancreatic cancer Knockdown in CFPAC-1 cells Knockdown decreased migration and invasion, and reduced adhesion to fibronection and collagen and increased adhesion to vitronectin [68] Anti-human ENO1 antibody…”

Enolase1 overexpression regulates the growth of gastric cancer cells and predicts poor survival

“…In head and neck cancer, ENO1 serves as a potential prognostic marker because it promotes the cellular transformation partially via inducing the chemokine C‐C motif chemokine ligand 20 (CCL20) . ENO1 also controls the expression of αv/β3 integrin and regulates the adhesion and metastasis of pancreatic cancer cells . In a genetically engineered mice model of pancreatic cancer, vaccination with ENO1 DNA prolongs the survival of mouse models .…”

“…8 ENO1 also controls the expression of αv/β3 integrin and regulates the adhesion and metastasis of pancreatic cancer cells. 9 In a genetically engineered mice model of pancreatic cancer, vaccination with ENO1 DNA prolongs the survival of mouse models. 10 However, it remains unknown whether ENO1 participates in human gastric cancer.…”