Project description:Microglia isolated from glioma patients gain anti-tumor activities upon poly (I:C) stimulation. Expression profiles of human tumor-infiltrating microglia/macrophages before (untreated) and after treatment with poly (I:C) for 48h (induced). Tumor-infiltrating microglia/macrophages were isolated from freshly excised brain tumors
Project description:The microenvironment has profound effect on macrophage phenotype. Here we examine the phenotype of macrophages infiltrating murine undifferentiated pleomorphic sarcomas. We used microarray to examine gene expression profile of tumor-associated macrophages in murine undifferentiated pleomorphic sarcomas. The immunosuppressive tumor microenvironment (TME) is a major barrier to immunotherapy. Within solid tumors, why monocytes preferentially differentiate into immunosuppressive tumor associated macrophages (TAMs) but not immunostimulatory dendritic cells (DCs) remains unclear. Using multiple murine sarcoma models, we found that the TME induced retinoic acid (RA) production by tumor cells, which polarized intratumoral monocyte differentiation towards TAMs and away from DCs via suppression of DC-promoting transcription factor Irf4. Genetic inhibition of RA production by tumor cells or pharmacologic inhibition of RA signaling within TME increased stimulatory monocyte-derived cells, enhanced T cell-dependent anti-tumor immunity and demonstrated striking synergy with immune checkpoint blockade. Further, RA responsive gene signature in human monocytes correlated with an immunosuppressive TME in multiple human tumors. RA has been long considered as an anti-cancer agent, but our work demonstrates its tumorigenic capability via myeloid-mediated immune suppression and provides proof of concept for targeting this pathway for tumor immunotherapy.
Project description:MicroRNAs (miRNAs) are non-coding molecules involved in post-transcriptional gene regulation that have been shown to modulate tumor cell proliferation and apoptosis and to act as oncogenes or tumor-suppressor genes. Although miRNAs have been linked to tumor progression, the connection between tumor-mediated immune modulation and miRNAs has yet to be explored. Specifically, how the miRNA dysregulation affects the monocyte-derived glioblastoma-infiltrating macrophages, the most abundant immune cell population within the glioblastoma microenvironment, and their immune suppressive properties has not been evaluated to date. Here we managed to purify the glioblastoma-infiltrating macrophages from the tumor microenvironment and compared their miRNA expression profile with the matched peripheral monocytes from the peripheral blood of the same GBM patient as well as with healthy donors. Of note, several most down-regulated miRNA candidates revealed in this study, including miR-142-3p, were also known for their role in mediating tumor-associated immunosuppression. These results suggest a novel approach to identify miRNA immune therapeutics using a two-step process: 1) screen miRNA expression from tumor-associated immune cells relative to normal immune cell, and 2) select and prioritize potential candidates on the basis of binding to immunosuppressive pathways or mechanisms. In the study presented here, 12 samples, including peripheral monocyte samples from 4 healthy donors, peripheral monocytes from 4 GBM patients and matched tumor-infiltrating macrophages extracted from the glioblastoma microenvironment, were used to acquire the miRNA expression profiles of 1732 unique mature miRNA sequences via the Phalanx Human miRNA OneArray Microarray v3 Platform.
Project description:Inducing graft acceptance without chronic immunosuppression remains an elusive goal in organ transplantation. Recent data demonstrate that non-self recognition by graft infiltrating macrophages initiates transplant rejection. Using an experimental transplantation mouse model, we isolated graft-infiltrating macrophages from two transplantation settings: untreated rejecting mice and treated with mTORi-HDL nanobiologics. We used microarrays to detail the global programme of gene expression underlying macrophage dependent organ transplant rejection and identified distinct classes of up-regulated genes during this process, which are down-regulated following tolerogenic treatment with mTORi-HDL nanobiologics.
Project description:Study goal is to disclose features of gene expressio profile of non-cancerous liver-infiltrating lymphocytes of type C hepatitis patients with hepatocellular carcinomas and tumor-infiltrating lymphocytes of type C hepatitis patients with hepatocellular carcinomas. Keywords: gene expression profile, non-cancerous liver-infiltrating lymphocytes, tumor-infiltrating lymphocytes, type C hepatitis, hepatocellular carcinoma Non-cancerous liver-infiltrating lymphocytes were obtained by laser capture microdissection from surgically resected liver tissues of 12 type C hepatitis patients with hepatocellular carcinoma. The mRNA was amplified and expression profile was comprehensively analyzed with reference RNA using oligo-DNA chip. Tumor-infiltrating lymphocytes were obtained by laser capture microdissection from surgically resected cancer tissues of 12 type C hepatitis patients with hepatocellular carcinoma. The mRNA was amplified and expression profile was comprehensively analyzed with reference RNA using oligo-DNA chip.
Project description:Regulatory T (Treg) cells are crucial for immune homeostasis but they also contribute to tumor immune evasion by promoting a suppressive tumor microenvironment (TME). Mice with Treg cell-restricted Neuropilin 1 deficiency show tumor resistance while maintaining peripheral immune homeostasis, thereby providing a controlled system to interrogate the impact of intratumoral Treg cells on the TME. Using this and other genetic models, we showed that Treg cells shaped the transcriptional landscape across multiple tumor-infiltrating immune cell types. Treg cells suppressed CD8+ T cell secretion of interferon- (IFN), which would otherwise block the activation of sterol regulatory element-binding protein 1 (SREBP1)-mediated fatty acid synthesis in immunosuppressive (M2-like) tumor-associated macrophages (TAMs). Thus, Treg cells indirectly but selectively sustained M2-like TAM metabolic fitness, mitochondrial integrity and survival. SREBP1 inhibition augmented the efficacy of immune checkpoint blockade, suggesting that targeting Treg cells or their modulation of lipid metabolism in M2-like TAMs could improve cancer immunotherapy. Microarray gene expression assay was performed to interogate the impact of fragile (Nrp1–/–) Tregs on the gloabal transcriptome oftumor immune infiltrates (CD45+ cells) at various time points over the course of tumor growth.