BACKGROUND: Extensive infiltration of brain tumors by microglia and macrophages is a hallmark of tumor progression, and yet the overall tumor microenvironment is characterized by an immunosuppressive phenotype. Here we identify esophageal cancer-related gene 4 (Ecrg4) as a novel thrombin-processed monocyte chemoattractant that recruits myeloid cells, promotes their activation, and leads to a blockade of tumor progression. METHODS: Both xenograft glioma and syngeneic glioma models were used to measure orthotopic tumor progression and overall survival. Flow cytometry and immunohistochemical analyses were performed to assess myeloid cell localization, recruitment, and activation. RESULTS: Ecrg4 promotes monocyte recruitment and activation of microglia in a T-/B-cell-independent mechanism, which leads to a reduction in glioma tumor burden and increased survival. Mutational analysis reveals that the biological activity of Ecrg4 is dependent on a thrombin-processing site at the C-terminus, inducing monocyte invasion in vivo and in vitro. Furthermore, tumor-induced myeloid cell recruitment is impaired in Ecrg4 knockout mice, leading to increased tumor burden and decreased survival. CONCLUSIONS: Together, these results identify Ecrg4 as a paracrine factor that activates microglia and is chemotactic for monocytes, with potential as an antitumor therapeutic.
BACKGROUND: Extensive infiltration of brain tumors by microglia and macrophages is a hallmark of tumor progression, and yet the overall tumor microenvironment is characterized by an immunosuppressive phenotype. Here we identify esophageal cancer-related gene 4 (Ecrg4) as a novel thrombin-processed monocyte chemoattractant that recruits myeloid cells, promotes their activation, and leads to a blockade of tumor progression. METHODS: Both xenograft glioma and syngeneic glioma models were used to measure orthotopic tumor progression and overall survival. Flow cytometry and immunohistochemical analyses were performed to assess myeloid cell localization, recruitment, and activation. RESULTS:Ecrg4 promotes monocyte recruitment and activation of microglia in a T-/B-cell-independent mechanism, which leads to a reduction in glioma tumor burden and increased survival. Mutational analysis reveals that the biological activity of Ecrg4 is dependent on a thrombin-processing site at the C-terminus, inducing monocyte invasion in vivo and in vitro. Furthermore, tumor-induced myeloid cell recruitment is impaired in Ecrg4 knockout mice, leading to increased tumor burden and decreased survival. CONCLUSIONS: Together, these results identify Ecrg4 as a paracrine factor that activates microglia and is chemotactic for monocytes, with potential as an antitumor therapeutic.
Authors: Jisook Lee; Caren Lund-Smith; Alexandra Borboa; Ana M Gonzalez; Andrew Baird; Brian P Eliceiri Journal: Brain Res Date: 2009-07-09 Impact factor: 3.252
Authors: Ana Maria Gonzalez; Sonia Podvin; Shuh-Yow Lin; Miles C Miller; Hannah Botfield; Wendy E Leadbeater; Andrew Roberton; Xitong Dang; Stuart E Knowling; Elena Cardenas-Galindo; John E Donahue; Edward G Stopa; Conrad E Johanson; Raul Coimbra; Brian P Eliceiri; Andrew Baird Journal: Fluids Barriers CNS Date: 2011-01-18
Authors: Sonia Podvin; Miles C Miller; Ryan Rossi; Jasmine Chukwueke; John E Donahue; Conrad E Johanson; Andrew Baird; Edward G Stopa Journal: JSM Alzheimers Dis Relat Dement Date: 2016-04-01
Authors: Steven Kao; Ashkaun Shaterian; David M Cauvi; Xitong Dang; Hyun Bae Chun; Antonio De Maio; Todd W Costantini; Raul Coimbra; Brian P Eliceiri; Andrew Baird Journal: Exp Lung Res Date: 2014-12-16 Impact factor: 2.459