Interleukin-17 mediated paracrine network promote tumor resistance to anti-angiogenic therapy
ABSTRACT: While angiogenesis inhibitors have provided significant clinical benefit as cancer therapeutics, the mechanisms of anti-VEGF resistance remain incompletely understood. We uncovered an interleukin-17 mediated paracrine network of signaling between the adaptive and innate immune system associated with resistance to anti-VEGF treatment in multiple tumor models. The expression of tumor-associated fibroblasts and tumor-associated granulocytes (defined as CD11b+Gr1+) and tumor-associated monocytic cells (defined as CD11b+Gr1-) were compared between wildtype and IL-17RC knockout tumor bearing mice.
Project description:We sought to identify genes that are differentially regulated in CD11b+Gr1+ cells after tumor challenging. Mice were challenged with LLC-RFP cells (5×10^6 cells, subcutaneous injection) for 9 days. Single cell suspensions were prepared from lungs of both tumor challenged and control wild type mice and stained with antibodies against CD11b and Gr1. Approximately 1×10^5 CD11b+GR1+ myeloid progenitor cells were sorted by FACS (Aria II, BD Bioscience). Total RNA was extracted from the sorted cells for microarray analysis. In this dataset, we include the expression data of CD11b+Gr1+ cells obtained from both control wild type and tumor challenged mice. These data were used to obtain 22 genes that are upregulated in response to tumor challenging. We analyzed 3 samples from control mice and 2 samples tumor challenged mice. The mean values of the groups were used in the analysis. Genes that were upregulated >2 fold were sorted out and generate the table in the Matrix datasheet.
Project description:Six-weeks old (C57Bl6, Cx3cr1gfp/+) mice were intraperitonealy infected with a low number (1.104) of L. monocytogenes (EGDe strain) in exponential growth phase (bacteria were grown in BHI at 108/ml, and diluted 10.000x in PBS immediately before injection). Group of three mice were euthanized, before infection. Peritoneal cells were recovered by peritoneal lavage. Cells from individual mice were stained with antibodies to CD11b (PECy7), Gr1 (APC), NK1.1, B220 and CD3 (PE), and F4/80 (biotin-conjugated followed by streptavidinpacific blue) for sorting. Gr1- monocytes were purified as NK1.1- CD3- B220- CD11b+ F4/80low Gr1-, gfphigh; Gr1+ monocytes were purified as NK1.1- CD3- B220- CD11b+ F4/80low Gr1+, gfpint; and polymorphonuclear cells were purified as NK1.1- CD3- B220- CD11b+ F4/80- Gr1high, gfp-. 1.103 cells from each mice, time point, and phenotype were purified by facs sorting according to their phenotype. Samples were kept at 4°C before and during the sort. Cells were directly sorted in the SuperAmp Lysis Buffer (Miltenyi Biotec, Bergisch Gladbach, Germany) using a FACS Aria cell-sorter (BD biosciences).
Project description:In the tumor microenvironment, CD11b(+)Gr1(+) bone marrow-derived cells are a predominant source of protumorigenic factors such as matrix metalloproteinases (MMP), but how distal tumors regulate these cells in the bone marrow is unclear. Here we addressed the hypothesis that the parathyroid hormone-related protein (PTHrP) potentiates CD11b(+)Gr1(+) cells in the bone marrow of prostate tumor hosts. In two xenograft models of prostate cancer, levels of tumor-derived PTHrP correlated with CD11b(+)Gr1(+) cell recruitment and microvessel density in the tumor tissue, with evidence for mediation of CD11b(+)Gr1(+) cell-derived MMP-9 but not tumor-derived VEGF-A. CD11b(+)Gr1(+) cells isolated from mice with PTHrP-overexpressing tumors exhibited relatively increased proangiogenic potential, suggesting that prostate tumor-derived PTHrP potentiates this activity of CD11b(+)Gr1(+) cells. Administration of neutralizing PTHrP monoclonal antibody reduced CD11b(+)Gr1(+) cells and MMP-9 in the tumors. Mechanistic investigations in vivo revealed that PTHrP elevated Y418 phosphorylation levels in Src family kinases in CD11b(+)Gr1(+) cells via osteoblast-derived interleukin-6 and VEGF-A, thereby upregulating MMP-9. Taken together, our results showed that prostate cancer-derived PTHrP acts in the bone marrow to potentiate CD11b(+)Gr1(+) cells, which are recruited to tumor tissue where they contribute to tumor angiogenesis and growth.
Project description:Recent studies suggest that tumor-associated CD11b(+)Gr1(+) myeloid cells contribute to refractoriness to antiangiogenic therapy with an anti-VEGF-A antibody. However, the mechanisms of peripheral mobilization and tumor-homing of CD11b(+)Gr1(+) cells are unclear. Here, we show that, compared with other cytokines [granulocyte-macrophage colony stimulating factor (GM-CSF), stromal derived factor 1alpha, and placenta growth factor], G-CSF and the G-CSF-induced Bv8 protein have preferential expression in refractory tumors. Treatment of refractory tumors with the combination of anti-VEGF and anti-G-CSF (or anti-Bv8) reduced tumor growth compared with anti-VEGF-A monotherapy. Anti-G-CSF treatment dramatically suppressed circulating or tumor-associated CD11b(+)Gr1(+) cells, reduced Bv8 levels, and affected the tumor vasculature. Conversely, G-CSF delivery to animals bearing anti-VEGF sensitive tumors resulted in reduced responsiveness to anti-VEGF-A treatment through induction of Bv8-dependent angiogenesis. We conclude that, at least in the models examined, G-CSF expression by tumor or stromal cells is a determinant of refractoriness to anti-VEGF-A treatment.
Project description:Antiangiogenic therapy is commonly used in the clinic, but its beneficial effects are short-lived, leading to tumor relapse within months. Here, we found that the efficacy of angiogenic inhibitors targeting the VEGF/VEGFR pathway was dependent on induction of the angiostatic and immune-stimulatory chemokine CXCL14 in mouse models of pancreatic neuroendocrine and mammary tumors. In response, tumors reinitiated angiogenesis and immune suppression by activating PI3K signaling in all CD11b+ cells, rendering tumors nonresponsive to VEGF/VEGFR inhibition. Adaptive resistance was also associated with an increase in Gr1+CD11b+ cells, but targeting Gr1+ cells was not sufficient to further sensitize angiogenic blockade because tumor-associated macrophages (TAMs) would compensate for the lack of such cells and vice versa, leading to an oscillating pattern of distinct immune-cell populations. However, PI3K inhibition in CD11b+ myeloid cells generated an enduring angiostatic and immune-stimulatory environment in which antiangiogenic therapy remained efficient.
Project description:Bv8 (prokineticin 2) expressed by Gr1(+)CD11b(+) myeloid cells is critical for VEGF-independent tumor angiogenesis. Although granulocyte colony-stimulating factor (G-CSF) has been shown to be a key inducer of Bv8 expression, the basis for Bv8 production in driving tumor angiogenesis is undefined. Because the cell adhesion molecule CEACAM1, which is highly expressed on Gr1(+)CD11b(+) myeloid cells, is known to regulate G-CSF receptor (G-CSFR) signaling, we hypothesized that CEACAM1 would regulate Bv8 production in these cells. In support of this hypothesis, we found that Bv8 expression was elevated in Gr1(+)CD11b(+) cells from Ceacam1-deficient mice implanted with B16 melanoma, increasing the infiltration of Gr1(+)CD11b(+) myeloid cells in melanoma tumors and enhancing their growth and angiogenesis. Furthermore, treatment with anti-Gr1 or anti-Bv8 or anti-G-CSF monoclonal antibody reduced myeloid cell infiltration, tumor growth, and angiogenesis to levels observed in tumor-bearing wild-type (WT) mice. Reconstitution of CEACAM1-deficient mice with WT bone marrow cells restored tumor infiltration of Gr1(+)CD11b(+) cells along with tumor growth and angiogenesis to WT levels. Treatment of tumor-bearing WT mice with anti-CEACAM1 antibody limited tumor outgrowth and angiogenesis, albeit to a lesser extent. Tumor growth in Ceacam1-deficient mice was not affected significantly in Rag(-/-) background, indicating that CEACAM1 expression in T and B lymphocytes had a negligible role in this pathway. Together, our findings show that CEACAM1 negatively regulates Gr1(+)CD11b(+) myeloid cell-dependent tumor angiogenesis by inhibiting the G-CSF-Bv8 signaling pathway.
Project description:Tumors engender an environment dominated by M2 differentiated tumor macrophages that support tumor invasion, metastases and escape from immune control. In this study, we demonstrate that following radiation therapy of tumors in mice there is an influx of tumor macrophages that polarize towards wound repair and immune suppression. To investigate changes in the phenotype of tumor macrophages following radiation therapy, we FACS sorted tumor macrophages from Panc02 tumors. We have previously shown that we can distinguish mature tumor macrophages from immature myeloid and MDSC populations by expression of Gr1 and IA (MHC class II). To isolate these sub-populations, we first gated CD11b+ cells in the untreated or irradiated tumors, then sorted the CD11b+IA+ macrophage population and the CD11b+Gr1hi MDSC population. Cytospins of the sorted populations demonstrates that the CD11b+Gr1hi MDSC predominantly have a granulocyte morphology and the CD11b+IA+ cells have a macrophage morphology in both the untreated and irradiated tumors. RNA was purified from CD11b+IA+ macrophages from untreated or irradiated tumors 1 day or 7 days following radiation therapy and Gene Expression Microarray analysis was performed. There are untreated and irradiated samples at time points 1 day and 7 days following radiation therapy. The experiment was repeated in entirety, generating a second gene array sample for each. For analysis, the untreated samples of 1 day and 7 days were grouped together.
Project description:Recent reports have shown the involvement of tumor burden as well as GM-CSF in supporting myeloid-derived suppressor cells (MDSC). However, it is not known what progenitor cells may differentiate into MDSC in the presence of GM-CSF, and whether FVBN202 transgenic mouse model of spontaneous breast carcinoma may exhibit distinct subset distribution of CD11b+Gr1+ cells. In addition, it is not known why CD11b+Gr1+ cells derived from tumor-free and tumor-bearing animals exhibit different functions. In this study, we determined that GM-CSF was one of the tumor-derived soluble factors that induced differentiation of CD11b-Gr1- progenitor cells from within monocytic/granulocytic bone marrow cells into CD11b+Gr1+ cells. We also showed that CD11b+Gr1+ cells in FVBN202 mice consisted of CD11b+Ly6G-Ly6C+ suppressive and CD11b+Ly6G+Ly6C+ non-suppressive subsets. Previously reported variations between tumor-free and tumor-bearing animals in the function of their CD11b+Gr1+ cells were found to be due to the variations in the proportion of these two subsets. Therefore, increasing ratios of CD11b+Gr1+ cells derived from tumor-free animals revealed their suppressive activity on T cells, in vitro. Importantly, GM-CSF supported the generation of CD11b+Ly6G-Ly6C+ suppressor subsets that inhibited proliferation as well as anti-tumor function of neu-specific T cells. These findings suggest revisiting the use of GM-CSF for the expansion of dendritic cells, ex vivo, for cell-based immunotherapy or as an adjuvant for vaccines for patients with cancer in whom MDSC play a major role in the suppression of anti-tumor immune responses.
Project description:By crossing LysM-Cre and TGF-? type II receptor (Tgfbr2) floxed mice we achieved specific deletion of Tgfbr2 in myeloid cells (Tgfbr2(MyeKO) mice). S.c.-injected (LLC, EL4-OVA) and implanted (MMTV-PyMT) carcinoma cells grow slower in Tgfbr2(MyeKO) mice. The number of CD45(+) cells in the tumor tissue was the same in both genotypes of mice, but upon analysis, the percentage of T cells (CD45(+)CD3(+)) in the KO mice was increased. By flow cytometry analysis, we did not detect any differences in the number and phenotype of TAMs, CD11b(+)Gr1(+), and DCs in Tgfbr2(MyeKO) compared with Tgfbr2(MyeWT) mice. ELISA and qRT-PCR data showed differences in myeloid cell functions. In Tgfbr2(MyeKO) TAMs, TNF-? secretion was increased, basal IL-6 secretion was down-regulated, TGF-? did not induce any VEGF response, and there was decreased MMP9 and increased MMP2 and iNOS expression. TGF-? did not have any effect on CD11b(+)Gr1(+) cells isolated from Tgfbr2(MyeKO) mice in the regulation of Arg, iNOS, VEGF, and CXCR4, and moreover, these cells have decreased suppressive activity relative to T cell proliferation. Also, we found that DCs from tumor tissue of Tgfbr2(MyeKO) mice have increased antigen-presented properties and an enhanced ability to stimulate antigen-specific T cell proliferation. We conclude that Tgfbr2 in myeloid cells has a negative role in the regulation of anti-tumorigenic functions of these cells, and deletion of this receptor decreases the suppressive function of CD11b(+)Gr1(+) cells and increases antigen-presenting properties of DCs and anti-tumorigenic properties of TAMs.
Project description:Myeloid derived suppressor cells (MDSCs) are an immunosuppressive population of immature myeloid cells found in advanced stage cancer patients and mouse tumor models. We have identified Cd38 gene as potentially playing an essential role in MDSC biology. To determine the diffences between CD38high and CD38 low MDSCs from tumor-bearing mice, we have conducted this microarray. In this dataset, we include the expression data obtained from sorted splenic CD38high CD11b+Gr1+ cells from tumor-bearing L2-Cre;p120f/f mice, compared to CD38low CD11b+Gr1+ cells from the same mice. Using these data, we have detected differential expression of 498 genes . The Nos2 gene was among the genes most upregulated in CD38high MDSCs. 8 total samples were analyzed: 3 pairs of CD38high and CD38 low MDSCs (coming from individual mice), as well a pair of CD38high and CD38low pulled MSDCs (splenocytes from 3 mice were pulled together for sorting to increase yields). Gene expression difference was determined by univariate test (two-sample t-test) with multivariate permutation test (10,000 random permutations). A cut-off p-value of less than 0.001 and minimum 2-fold expression change were used to identify genes with significant expression differences between the two groups.