Project description:In breast cancer, interactions between tumor cells and surrounding stromal cells, such as macrophages, are critical for tumor growth, progression, and therapeutic response. Recent studies have highlighted the complex nature and heterogeneous populations of macrophages associated with both tumor promoting and tumor inhibiting phenotypes. Identifying the specific signaling pathways that regulate macrophage function within the tumor microenvironment will lead to new approaches that suppress tumor promoting functions while enhancing their anti-tumor functions. We demonstrated STAT5 (signal transducer and activator of transcription 5) is robustly activated in tumor-associated macrophages and that granulocyte-macrophage colony stimulating factor (GM-CSF) is a major cytokine stimulating this pathway. To define impacts of GM-CSF/STAT5 on macrophage function, we used in vitro and in vivo models to demonstrate that STAT5 has a significant role in stimulating expression profiles in macrophages consistent with an anti-tumor, adaptive immune response. Our results also indicate that loss of STAT5 in the myeloid lineage leads to enhanced metastatic disease. These findings reveal that disrupted STAT5 signaling in tumor-associated macrophages supports tumor progression, which suggests STAT5 may regulate anti-tumor macrophage function. Understanding how to enhance the anti-tumor capacity of macrophages will be vital in developing effective treatment strategies for patients with aggressive breast cancer.
Project description:To further analyze the change of microRNA(miRNA) between normal peritoneal macrophage(PEC) and TAM from early tumor(12 days after 4T1 cell injection) or TAM from late tumor(21 days after 4T1 cell injection) , we employed Agilent mouse microRNA microarray Rel 12.0 as a discovery platform to identify miRNAs Total RNA from peritoneal macrophage and TAM of early tumor (tumor formed for 12days after BALB/c mice injected wth 4T1 cell) or TAM of late tumor(tumor formed for 21days after BALB/c mice injected with 4T1 cell) were extracted and analyzed using Agilent mouse microRNA microarray platform, and changes of miRNA were screened out. Agilent mouse microRNA microarray is designed for the profiling of mouse miRNA .627 mouse miRNA and 39 mouse virus-related miRNA can be detected by our microRNA microarray.
Project description:We studied the impact of Ptdss1 knockdown in PyMT mouse mammary tumor cells and of Csf1-driven Mertk KO (macrophage-specfic) on tumor growth and the associated macrophage phenotype in an orthotopic tumor model. To gain insight into the reasons underlying tumor rejection once either Ptdss1 was deleted in tumor cells or Mertk was knocked out in macrophages, whole transcriptome profiling of FACS-sorted tumor-associated macrophages of WT or macrophage-specific Mertk KO mice receiving either control tumor cells or Ptdss1 knockdown tumor cells was performed via next generation mRNA sequencing, at least in triplicates, on a NextSeq 500 high-throughput bench top sequencer.
Project description:To further analyze the change of microRNA(miRNA) between normal peritoneal macrophage(PEC) and TAM from early tumor(12 days after 4T1 cell injection) or TAM from late tumor(21 days after 4T1 cell injection) , we employed Agilent mouse microRNA microarray Rel 12.0 as a discovery platform to identify miRNAs
Project description:The concept of macrophage niches has redefined the classification of macrophages, moving beyond ontogeny and function to encompass the mutually beneficial loop of signals in a given tissue environment. As such, tissue-resident macrophages adapt to local environmental signals within and between tissues to acquire specific functional adaptations. Neoplastic transition transforms the tissue environment, which then raises the question as to how existing macrophage subsets and their niche contribute to the tumor-associated macrophage (TAM) compartment. By combining single cell RNA sequencing and 2-photon imaging, we discovered that considerable TAM heterogeneity in mammary breast tumor is driven by niches that exist prior to tumor development, macrophage localization within the tumor and the stage of tumor malignancy. The differentiation of TAM subsets was associated with distinct signaling paths, homing and transcription factor signatures. We find similar functional heterogeneity in human breast TAMs. In overview, we show that specific niches within the tumor rather than defined activation states (e.g. the M1/M2 dichotomy) are the major drivers of TAM plasticity and heterogeneity. The distinctions created by this analysis show how treatments of different tumor indications should propose targeting specific TAMs at this niche/pathway level.
Project description:Recent studies have shown the tumor extracellular matrix (ECM) associates with immunosuppression, and that targeting the ECM can improve immune infiltration and immunotherapy response. A question that remains is whether the ECM is directly educating the immune phenotypes seen in cancer. We identified a tumor-associated macrophage (TAM) population correlated with poor prognosis, interruption of the cancer immunity cycle, and tumor ECM composition. To investigate whether ECM was capable of generating the TAM phenotype seen, we developed a decellularized tissue model that retains the native ECM architecture and composition. Macrophages cultured on decellularized ovarian metastasis shared transcriptional profiles with the TAMs found in human tissues. ECM educated macrophages have a tissue remodeling and immunoregulatory phenotype, inducing altered T cell function. We conclude that the tumor ECM is directly educating this macrophage population found in cancer tissues. Therefore, current and emerging cancer therapies that target the tumor ECM may be tailored to improve macrophage phenotype and their downstream regulation of immunity.