Project description:Macrophages, play an essential role in promoting tumor growth by affecting angiogenesis, immune suppression, invasion and metastasis. The signal transduction events within macrophages which encode the complex cascade of events required for tumor growth and polarization of macrophages are poorly understood. We have discovered an ECM dependent signaling pathway in macrophages that regulates M2 macrophage differentiation, tumor growth, invasion and metastasis. We provide direct evidence that a macrophage autonomous, M-NM-14M-NM-21 integrin dependent Syk-Rac2 signaling axis acts in concert with the p110 isoform (PTEN-PI-3 kinase pathway) to control metastasis. Bone marrow derived macrophages from five wild type and five Rac2 -/- mutant C57BL mice.
Project description:Macrophages, play an essential role in promoting tumor growth by affecting angiogenesis, immune suppression, invasion and metastasis. The signal transduction events within macrophages which encode the complex cascade of events required for tumor growth and polarization of macrophages are poorly understood. We have discovered an ECM dependent signaling pathway in macrophages that regulates M2 macrophage differentiation, tumor growth, invasion and metastasis. We provide direct evidence that a macrophage autonomous, α4β1 integrin dependent Syk-Rac2 signaling axis acts in concert with the p110 isoform (PTEN-PI-3 kinase pathway) to control metastasis. SmoA1 Tg MB tumor cells were sorted into CD15+ and CD15- populations. RNA from these samples were hybridized to Affymetrix Mouse Genome 1.0 ST array.
Project description:Macrophages, play an essential role in promoting tumor growth by affecting angiogenesis, immune suppression, invasion and metastasis. The signal transduction events within macrophages which encode the complex cascade of events required for tumor growth and polarization of macrophages are poorly understood. We have discovered an ECM dependent signaling pathway in macrophages that regulates M2 macrophage differentiation, tumor growth, invasion and metastasis. We provide direct evidence that a macrophage autonomous, α4β1 integrin dependent Syk-Rac2 signaling axis acts in concert with the p110 isoform (PTEN-PI-3 kinase pathway) to control metastasis.
Project description:Macrophages, play an essential role in promoting tumor growth by affecting angiogenesis, immune suppression, invasion and metastasis. The signal transduction events within macrophages which encode the complex cascade of events required for tumor growth and polarization of macrophages are poorly understood. We have discovered an ECM dependent signaling pathway in macrophages that regulates M2 macrophage differentiation, tumor growth, invasion and metastasis. We provide direct evidence that a macrophage autonomous, α4β1 integrin dependent Syk-Rac2 signaling axis acts in concert with the p110 isoform (PTEN-PI-3 kinase pathway) to control metastasis.
Project description:We recently identified the nonreceptor tyrosine kinase syk as a tumor suppressor in pancreatic ductal adenocarcinoma cells. Reintroduction of syk into Panc1 cells promoted a more differentiated phenotype and retarded invasion and tumorigenic growth. Gene array analysis identified over 2,000 transcripts differentially expressed at FDR<0.01. Among these were members of the MMP2 axis, which were subsequently shown to regulate Panc1 invasion. Experiment Overall Design: Affymetrix global gene arrays were used to analyse differences in gene expression patterns in Panc1 cells stably reexpressing syk, or vector-only mock controls. RNA was harvested from cells grown under identical conditions in standard culture.
Project description:Macrophages (MΘs) play a critical role in tumor growth, immunosuppression and inhibition of adaptive immune responses in cancer. Hence, targeting signaling pathways in MΘs that promote tumor immunosuppression will provide therapeutic benefit. PI3Kγ has been recently established by our group and others as a novel immuno-oncology target. Herein, we report that macrophage Syk drives polarization of immunosuppressive macrophages which establish an immunosuppressive tumor microenvironment in in vivo syngeneic tumor models. Genetic or pharmacological blockade of Syk in MΘs promotes a pro-inflammatory MΘ phenotype, restores CD8+ T cell activity, destabilizes HIF under hypoxia, and stimulates antitumor immune response. Moreover, we have developed in silico the “first in class” dual Syk/PI3K inhibitor, SRX3207, for the combinatorial inhibition of Syk and PI3K in one small molecule to activate anti-tumor immunity in vivo. This chemotype shows great efficacy in various tumor models and represents a new therapeutic approach to treat devastating cancers. Significance: Our data indicate a central role of Syk in macrophage transcriptional programming leading to inhibition of adaptive immune responses. Furthermore, SRX3207 blocks macrophage expression of immunosuppressive factors and activates anti-tumor immune responses, validating the concept of combined Syk and PI3K inhibition as an effective approach to treat macrophage driven cancers.
Project description:We recently identified the nonreceptor tyrosine kinase syk as a tumor suppressor in pancreatic ductal adenocarcinoma cells. Reintroduction of syk into Panc1 cells promoted a more differentiated phenotype and retarded invasion and tumorigenic growth. Gene array analysis identified over 2,000 transcripts differentially expressed at FDR<0.01. Among these were members of the MMP2 axis, which were subsequently shown to regulate Panc1 invasion. Keywords: Genetic manipulation (stable transgene expression)
