Project description:The M2 phenotype is controlled by key transcription factors such as STAT6. We describe an engineered exosome therapeutic candidate delivering an antisense oligonucleotide (ASO) targeting STAT6 (exoASO-STAT6), which preferentially silences STAT6 expression in tumor-associated macrophages (TAMs). We demonstrate that administration of exoASO-STAT6 reprograms TAMs to an M1 phenotype, leading to the induction of nitric oxide synthase 2 (NOS2) and remodeling of the TAMs.
Project description:Effectiveness of checkpoint immunotherapy in cancer can be undermined by immunosuppressive tumor-associated macrophages (TAMs) with an M2 phenotype. Reprogramming TAMs toward a proinflammatory M1 phenotype is a novel approach to induce antitumor immunity. The M2 phenotype is controlled by key transcription factors such as signal transducer and activator of transcription 6 (STAT6), which have been "undruggable" selectively in TAMs. We describe an engineered exosome therapeutic candidate delivering an antisense oligonucleotide (ASO) targeting STAT6 (exoASO-STAT6), which selectively silences STAT6 expression in TAMs. In syngeneic models of colorectal cancer and hepatocellular carcinoma, exoASO-STAT6 monotherapy results in >90% tumor growth inhibition and 50 to 80% complete remissions. Administration of exoASO-STAT6 leads to induction of nitric oxide synthase 2 (NOS2), an M1 macrophage marker, resulting in remodeling of the tumor microenvironment and generation of a CD8 T cell-mediated adaptive immune response. Collectively, exoASO-STAT6 represents the first platform targeting transcription factors in TAMs in a highly selective manner.
Project description:Stephen Paget first proposed, in 1889, that organ distribution of metastases is a non-random event, yet metastatic organotropism remains one of the greatest mysteries in cancer biology. Here, we demonstrate that exosomes released by lung-, liver- and brain-tropic tumor cells fuse preferentially with resident cells at their predicted destination, such as fibroblasts and epithelial cells in the lung, Kupffer cells in the liver, and endothelial cells in the brain. We found that exosome homing to organ-specific cell types prepares the pre-metastatic niche and that treatment with exosomes derived from lung tropic models can redirect metastasis to the lung. Proteomic profiling of exosomes revealed distinct integrin expression patterns associated with each organ-specific metastasis. Whereas exosomal integrins α6β4 and α6β1 were associated with lung metastasis, exosomal integrins αvβ5 and αvβ3 were linked with liver and brain metastases, respectively. Targeting α6β4 and αvβ5 integrins decreased exosome uptake and metastasis in the lung and liver, respectively. Importantly, we demonstrate that exosome uptake activates a cell-specific subset of S100 family genes, known to support cell migration and niche formation. Finally, our clinical data indicate that integrin-expression profiles in circulating plasma exosomes from cancer patients could be used to predict organ-specific metastasis. Education of human von Kupffer cells in vitro with human pancreatic cancer exosomes
Project description:We used microarrays to find Stat6 dependent genes in control and IL-4 exposed bone marrow derived macrophages. Alternatively activated macrophages (AAM) accumulate in tissues during Th2-associated immune responses like helminth infections and allergic disorders. These cells possess potent inhibitory activity against T cells. The differentiation of AAM depends on IL-4/IL-13-mediated activation of the transcription factor Stat6. Stat6 is also required in AAM to induce several genes, such as YM1, FIZZ1 and Arginase1.
Project description:dataset of 60 patients with ER-positive primary breast cancer and treated with tamoxifen monotherapy for 5 years. Data were generated from LCMed cancer cells. Sample_keyword: breast cancer, tamoxifen, recurrence Keywords: other
Project description:dataset of 60 patients with ER-positive primary breast cancer and treated with tamoxifen monotherapy for 5 years. Data were generated from whole tissue sections of breast cancers. Sample_keyword: breast cancer, tamoxifen, recurrence Keywords: other
Project description:Evidence suggests that BRCA1 mutation associated tumors have increased sensitivity to DNA damaging agents like cisplatin. Sporadic triple negative breast cancers (TNBC) have many phenotypic similarities to BRCA1 tumors and may have a similar sensitivity to cisplatin. We tested the efficacy of cisplatin monotherapy in 28 TNBC patients in a single arm neoadjuvant trial with outcome measured by pathologic treatment response quantified using the Miller-Payne scale. We used microarrays gene expression profiles to determine tumor subtype of each trial tumor sample and to test various expression signatures for association with pathologic response to cisplatin. Pretreatment tumor samples from the clinical trial (N=24 with adequate tissue) were used for RNA extraction, linear amplification, biotin labeling and hybridization to Affymetrix U133 plus 2.0 arrays. A reference set of 51 primary breast tumors representing all subtypes of breast cancer were processed in a similar manner to include linear amplification, and hybridized to Affymetrix arrays.
Project description:IL-4/STAT6-regulated transcriptome and proteome were compared in primary B cells isolated from wild-type and STAT6-deficient mice. B cells were purified from the spleen and stimulated in vitro with anti-CD40 and LPS or anti-IgM-F(ab)2 in the presence or absence of IL-4. Transcriptome analysis was performed with oligonucleotide microarrays. Global relative quantification of proteins was achieved by gel-enhanced label-free liquid chromatography/mass spectrometry (LC/MS). Hierarchical clustering and principal component analysis revealed that IL-4-induced changes of the transcriptome were almost completely dependent on STAT6. In contrast, the quantitative proteome analysis revealed that the expression of many IL-4-regulated proteins changes even in the absence of STAT6. The top 75 proteins with changes in abundance levels induced by IL-4 in a STAT6-dependent manner were also found to be regulated at the transcriptional level. Most of these proteins were not previously known to be regulated by STAT6 in B cells. We confirmed the MS-based quantitative proteome data by flow cytometric and Western blot analysis of selected proteins. This study provides a framework for further functional characterization of STAT6-regulated proteins in B cells that might be involved in germinal center formation and class switch recombination.
Project description:We used microarrays to find Stat6 dependent genes in control and IL-4 exposed bone marrow derived macrophages. Alternatively activated macrophages (AAM) accumulate in tissues during Th2-associated immune responses like helminth infections and allergic disorders. These cells possess potent inhibitory activity against T cells. The differentiation of AAM depends on IL-4/IL-13-mediated activation of the transcription factor Stat6. Stat6 is also required in AAM to induce several genes, such as YM1, FIZZ1 and Arginase1. Macrophages were differentiated from bone marrow cells in supplemented RPMI 1640 for 7 days in the presence of 10% supernatant from the M-CSF producing fibroblast cell line L929. After removal of nonadherent cells, macrophages were detached using 5mM EDTA treatment, washed, counted, and replated at a density of 10x6 cells/mL. Macrophages were cultured for 24 hours in medium (control) or in the presence of IL-4 (10mg/mL). F4/80 positive macrophages were sorted with a purity of 99% and RNA was isolated (Trizol/Chloroform) according to the manufacturer's instructions. RNA was labeled (biotin), fragmented, and hybridized to the arrays according to the manufacturer's recommendations.
Project description:Stephen Paget first proposed, in 1889, that organ distribution of metastases is a non-random event, yet metastatic organotropism remains one of the greatest mysteries in cancer biology. Here, we demonstrate that exosomes released by lung-, liver- and brain-tropic tumor cells fuse preferentially with resident cells at their predicted destination, such as fibroblasts and epithelial cells in the lung, Kupffer cells in the liver, and endothelial cells in the brain. We found that exosome homing to organ-specific cell types prepares the pre-metastatic niche and that treatment with exosomes derived from lung tropic models can redirect metastasis to the lung. Proteomic profiling of exosomes revealed distinct integrin expression patterns associated with each organ-specific metastasis. Whereas exosomal integrins α6β4 and α6β1 were associated with lung metastasis, exosomal integrins αvβ5 and αvβ3 were linked with liver and brain metastases, respectively. Targeting α6β4 and αvβ5 integrins decreased exosome uptake and metastasis in the lung and liver, respectively. Importantly, we demonstrate that exosome uptake activates a cell-specific subset of S100 family genes, known to support cell migration and niche formation. Finally, our clinical data indicate that integrin-expression profiles in circulating plasma exosomes from cancer patients could be used to predict organ-specific metastasis.