Pro-tumor M2 Macrophages Research Articles

Intratumoral IL17-producing cells infiltration correlate with antitumor immune contexture and improved response to adjuvant chemotherapy in gastric cancer.

Tumor IL17-producing (IL17A+) cells infiltration has different prognostic values among various cancers. The objective of this study was to assess the effect of IL17A+ cells in gastric cancer. The study included two patient cohorts, the Cancer Genome Atlas cohort (TCGA, n = 351) and the Zhongshan Hospital cohort (ZSHC, n = 458). The TCGA and ZSHC were used for mRNA-related and cells infiltration-related analyses, respectively. The roles of IL17A mRNA and IL17A+ cells in overall survival (OS), response to adjuvant chemotherapy (ACT), and immune contexture were evaluated. Another independent cohort was included to identify the correlation between mRNA of IL17A and IL17A+ cells infiltration (the preliminary Zhongshan Hospital cohort, PZSHC, n = 21). The infiltration of IL17A+ cells was positively correlated with the expression of IL17A mRNA (Spearman's ρ = 0.811; P < 0.001). High IL17A mRNA expression and intratumoral IL17A+ cells were correlated with improved OS and remained to be significant after adjusted for confounders. Patients with TNM II/III disease whose tumor present higher intratumoral IL17A+ cells or lower peritumoral IL17A+ cells can benefit more from ACT. Elevated IL17A mRNA expression and increased intratumoral IL17A+ cells infiltration was associated with more antitumor mast cells and nature killer cells infiltration and less pro-tumor M2 macrophages infiltration. High IL17A mRNA expression represented a Th17 cells signature and immune response process and was correlated with increased cytotoxic GZMA, GZMB, IFNG, PRF1, and TNFSF11 expression. IL17A mRNA expression and intratumoral IL17A+ cells infiltration were correlated with antitumor immune contexture. IL17A+ cells infiltration could be used as an independent prognostic biomarker for OS and predictive biomarker for superior response to ACT, and further prospective validation needs to be conducted.

Oncolytic virotherapy in glioblastoma patients induces a tumor macrophage phenotypic shift leading to an altered glioblastoma microenvironment.

Immunosuppressive protumoral M2 macrophages are important in pathogenesis, progression, and therapy resistance in glioblastoma (GBM) and provide a target for therapy. Recently oncolytic virotherapy in murine models was shown to change these M2 macrophages toward the pro-inflammatory and antitumoral M1 phenotype. Here we study the effects of the oncolytic virotherapy Delta24-RGD in humans, using both in vitro models and patient material. Human monocyte-derived macrophages were co-cultured with Delta24-RGD-infected primary glioma stem-like cells (GSCs) and were analyzed for their immunophenotype, cytokine expression, and secretion profiles. Cerebrospinal fluid (CSF) from 18 Delta24-RGD-treated patients was analyzed for inflammatory cytokine levels, and the effects of these CSF samples on macrophage phenotype in vitro were determined. In addition, tumor macrophages in resected material from a Delta24-RGD-treated GBM patient were compared with 5 control GBM patient samples by flow cytometry. Human monocyte-derived M2 macrophages co-cultured with Delta24-RGD-infected GSCs shifted toward an M1-immunophenotype, coinciding with pro-inflammatory gene expression and cytokine production. This phenotypic switch was induced by the concerted effects of a change in tumor-produced soluble factors and the presence of viral particles. CSF samples from Delta24-RGD-treated GBM patients revealed cytokine levels indicative of a pro-inflammatory microenvironment. Furthermore, tumoral macrophages in a Delta24-RGD-treated patient showed significantly greater M1 characteristics than in control GBM tissue. Together these in vitro and patient studies demonstrate that local Delta24-RGD therapy may provide a therapeutic tool to promote a prolonged shift in the protumoral M2 macrophages toward M1 in human GBM, inducing a pro-inflammatory and potentially tumor-detrimental microenvironment.

Modeling Macrophage Polarization and Its Effect on Cancer Treatment Success.

Positive feedback loops drive immune cell polarization toward a pro-tumor phenotype that accentuates immunosuppression and tumor angiogenesis. This phenotypic switch leads to the escape of cancer cells from immune destruction. These positive feedback loops are generated by cytokines such as TGF-β, Interleukin-10 and Interleukin-4, which are responsible for the polarization of monocytes and M1 macrophages into pro-tumor M2 macrophages, and the polarization of naive helper T cells intopro-tumor Th2 cells. In this article, we present a deterministic ordinary differential equation (ODE) model that includes key cellular interactions and cytokine signaling pathways that lead to immune cell polarization in the tumor microenvironment. The model was used to simulate various cancer treatments in silico. We identified combination therapies that consist of M1 macrophages or Th1 helper cells, coupled with an anti-angiogenic treatment, that are robust with respect to immune response strength, initial tumor size and treatment resistance. We also identified IL-4 and IL-10 as the targets that should be neutralized in order to make these combination treatments robust with respect to immune cell polarization. The model simulations confirmed a hypothesis based on published experimental evidence that a polarization into the M1 and Th1 phenotypes to increase the M1-to-M2 and Th1-to-Th2 ratios plays a significant role in treatment success. Our results highlight the importance of immune cell reprogramming as a viable strategy to eradicate a highly vascularized tumor when the strength of the immune response is characteristically weak and cell polarization to the pro-tumor phenotype has occurred.

Dual‐Targeting to Cancer Cells and M2 Macrophages via Biomimetic Delivery of Mannosylated Albumin Nanoparticles for Drug‐Resistant Cancer Therapy

AbstractMultidrug resistance (MDR) is an issue that is not only related to cancer cells but also associated with the tumor microenvironments. MDR involves the complicated cancer cellular events and the crosstalk between cancer cells and their surroundings. Ideally, an effective system against MDR cancer should take dual action on both cancer cells and tumor microenvironments. The authors find that both the drug‐resistant colon cancer cells and the protumor M2 macrophages highly express two nutrient transporters, i.e., secreted protein acidic and rich in cysteine (SPARC) and mannose receptors (MR). By targeting SPARC and MR, a system can act on both cancer cells and M2 macrophages. Herein the authors develop a mannosylated albumin nanoparticles with coencapsulation of different drugs, i.e., disulfiram/copper complex (DSF/Cu) and regorafenib (Rego). The results show that combination therapy of DSF/Cu and Rego efficiently inhibits the growth of drug‐resistant colon tumor, and the combination has not been reported yet for use in anticancer treatment. The system significantly improves the treatment outcomes in the animal model bearing drug‐resistant tumors. The therapeutic mechanisms involve enhanced apoptosis, upregulation of intracellular ROS, anti‐angiogenesis, and tumor‐associated macrophage “re‐education.” This strategy is characterized by dual targeting to and the simultaneous action on cancer cells and M2 macrophages, with biomimetic codelivery of a novel drug combination.

Abstract 5437: miR-302b as adjuvant therapeutic tool to improve chemotherapy efficacy in human triple-negative breast cancer

Abstract Introduction: Triple-negative breast cancer (TNBC) accounts for 15-20% of all breast cancer cases, with the worst outcome of all subtypes. For TNBC, still lacking targeted therapies, the only therapeutic option is currently chemotherapy, and despite a good initial response, patients often develop drug resistance. MiRNAs can modulate chemoresistance by affecting DNA repair, cell cycle progression, apoptosis and also tumor microenvironment. Macrophages constitute a major component of the immune microenvironment of cancer and pro-tumor M2 macrophages have been associated with resistance to chemotherapeutic treatments. Our previous data showed that miR-302b over-expression enhances sensitivity to cisplatin in breast cancer cell lines by targeting directly E2F1 and indirectly ATM. Here, we investigated the potential of miR-302b as a therapeutic tool to enhance cisplatin response in a TNBC mouse model and which pathways are involved in this mechanism both in tumor cells and microenvironment. Moreover, miR-302b prognostic value was assessed in a cohort of TNBC patients with available clinical outcome . Finally, we evaluated if miR-302b enhances the sensitivity to doxorubicin, another chemotherapeutic agent used as first-line therapy in TNBC patients. Material and method: MDA-MB-231 TNBC cells were injected into the mammary fat pad of female SCID mice and then treated with lipid nanoparticles containing miR-302b or cel-miR-67 control, alone or in combination with cisplatin. Gene expression profile on collected tumors was performed by microarray and tumor sections were stained with anti-arginase 1 (M2 marker) to evaluate the number of M2 macrophages. MiR-302b expression was assessed in 39 TNBC treated with chemotherapy in adjuvant setting, and associated with prognosis. Finally, MDA-MB-231 cells were transfected with miR-302b precursor or control treated with doxorubicin for 24h and then assessed for cell viability. Results: Our results show that miR-302b combination with cisplatin significantly impaired tumor growth in comparison with cel-67 control and cisplatin (p= 0.03), and reduced the number of M2 macrophages in the tumor microenvironment (p=0.005). Moreover, gene expression profile of collected tumors confirm immune system modulation. Notably, miR-302b expression was associated with disease-free survival and overall survival in TNBC patients treated with adjuvant chemotherapy. Furthermore, we found that miR-302b also enhances sensitivity to doxorubicin in vitro, affecting cell viability and cell cycle transition through E2F1 regulation. Conclusion: Our data demonstrate that miR-302b can be exploited as a new therapeutic tool to improve the response to chemotherapy, modulating tumor microenvironment. Moreover, this miRNA has prognostic significance in TNBC patients, and might also represent an useful predictive biomarker for response to chemotherapy. Citation Format: Alessandra Cataldo, Ilaria Plantamura, Elvira D'Ippolito, Sandra Romero-Cordoba, Sara Baroni, Valeria Cancilia, Claudio Tripodo, Dario Palmieri, Marilena V. Iorio. miR-302b as adjuvant therapeutic tool to improve chemotherapy efficacy in human triple-negative breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5437. doi:10.1158/1538-7445.AM2017-5437

M3 Macrophages Stop Division of Tumor Cells In Vitro and Extend Survival of Mice with Ehrlich Ascites Carcinoma.

BackgroundM1 macrophages target tumor cells. However, many tumors produce anti-inflammatory cytokines, which reprogram the anti-tumor M1 macrophages into the pro-tumor M2 macrophages. We have hypothesized that the problem of pro-tumor macrophage reprogramming could be solved by using a special M3 switch phenotype. The M3 macrophages, in contrast to the M1 macrophages, should respond to anti-inflammatory cytokines by increasing production of pro-inflammatory cytokines to retain its anti-tumor properties. Objectives of the study were to form an M3 switch phenotype in vitro and to evaluate the effect of M3 macrophages on growth of Ehrlich ascites carcinoma (EAC) in vitro and in vivo.Material/MethodsTumor growth was initiated by an intraperitoneal injection of EAC cells into C57BL/6J mice.Results1) The M3 switch phenotype can be programed by activation of M1-reprogramming pathways with simultaneous inhibition of the M2 phenotype transcription factors, STAT3, STAT6, and/or SMAD3. 2) M3 macrophages exerted an anti-tumor effect both in vitro and in vivo, which was superior to anti-tumor effects of cisplatin or M1 macrophages. 3) The anti-tumor effect of M3 macrophages was due to their anti-proliferative effect.ConclusionsDevelopment of new biotechnologies for restriction of tumor growth using in vitro reprogrammed M3 macrophages is very promising.

Guidance Molecule SEMA3A Restricts Tumor Growth by Differentially Regulating the Proliferation of Tumor-Associated Macrophages.

Accumulation of tumor-associated macrophages (TAM) correlates with malignant progression, immune suppression, and poor prognosis. In this study, we defined a critical role for the cell-surface guidance molecule SEMA3A in differential proliferative control of TAMs. Tumor cell-derived SEMA3A restricted the proliferation of protumoral M2 macrophages but increased the proliferation of antitumoral M1, acting through the SEMA3A receptor neuropilin 1. Expansion of M1 macrophages in vivo enhanced the recruitment and activation of natural killer (NK) cells and cytotoxic CD8(+) T cells to tumors, inhibiting their growth. In human breast cancer specimens, we found that immunohistochemical levels of SEMA3A correlated with the expression of genes characteristic of M1 macrophages, CD8(+) T cells, and NK cells, while inversely correlating with established characters of malignancy. In summary, our results illuminate a mechanism whereby the TAM phenotype is controlled and identify the cell-surface molecule SEMA3A as a candidate for therapeutic targeting. Cancer Res; 76(11); 3166-78. ©2016 AACR.

Ang-2/VEGF bispecific antibody reprograms macrophages and resident microglia to anti-tumor phenotype and prolongs glioblastoma survival

Inhibition of the vascular endothelial growth factor (VEGF) pathway has failed to improve overall survival of patients with glioblastoma (GBM). We previously showed that angiopoietin-2 (Ang-2) overexpression compromised the benefit from anti-VEGF therapy in a preclinical GBM model. Here we investigated whether dual Ang-2/VEGF inhibition could overcome resistance to anti-VEGF treatment. We treated mice bearing orthotopic syngeneic (Gl261) GBMs or human (MGG8) GBM xenografts with antibodies inhibiting VEGF (B20), or Ang-2/VEGF (CrossMab, A2V). We examined the effects of treatment on the tumor vasculature, immune cell populations, tumor growth, and survival in both the Gl261 and MGG8 tumor models. We found that in the Gl261 model, which displays a highly abnormal tumor vasculature, A2V decreased vessel density, delayed tumor growth, and prolonged survival compared with B20. In the MGG8 model, which displays a low degree of vessel abnormality, A2V induced no significant changes in the tumor vasculature but still prolonged survival. In both the Gl261 and MGG8 models A2V reprogrammed protumor M2 macrophages toward the antitumor M1 phenotype. Our findings indicate that A2V may prolong survival in mice with GBM by reprogramming the tumor immune microenvironment and delaying tumor growth.

CD86⁺/CD206⁺, Diametrically Polarized Tumor-Associated Macrophages, Predict Hepatocellular Carcinoma Patient Prognosis.

Tumor-associated macrophages (TAMs), the most abundant infiltrating immune cells in tumor microenvironment, have distinct functions in hepatocellular carcinoma (HCC) progression. CD68+ TAMs represent multiple polarized immune cells mainly containing CD86+ antitumoral M1 macrophages and CD206+ protumoral M2 macrophages. TAMs expression and density were assessed by immunohistochemical staining of CD68, CD86, and CD206 in tissue microarrays from 253 HCC patients. Clinicopathologic features and prognostic value of these markers were evaluated. We found that CD68+ TAMs were not associated with clinicopathologic characteristics and prognosis in HCC. Low presence of CD86+ TAMs and high presence of CD206+ TAMs were markedly correlated with aggressive tumor phenotypes, such as multiple tumor number and advanced tumor-node-metastasis (TNM) stage; and were associated with poor overall survival (OS) (p = 0.027 and p = 0.024, respectively) and increased time to recurrence (TTR) (p = 0.037 and p = 0.031, respectively). In addition, combined analysis of CD86 and CD206 provided a better indicator for OS (p = 0.011) and TTR (p = 0.024) in HCC than individual analysis of CD86 and CD206. Moreover, CD86+/CD206+ TAMs predictive model also had significant prognosis value in α-fetoprotein (AFP)-negative patients (OS: p = 0.002, TTR: p = 0.005). Thus, these results suggest that combined analysis of immune biomarkers CD86 and CD206 could be a promising HCC prognostic biomarker.

Microenvironmental effects limit efficacy of thymoquinone treatment in a mouse model of ovarian cancer.

BackgroundOvarian cancer is the most lethal gynecologic malignancy, with limited treatment options for chemoresistant disease. An important link between inflammation and peritoneal spread of ovarian cancer is NF-κB signaling. Thymoquinone (TQ) exerts multiple anti-tumorigenic cellular effects, including NF-κB inhibition. We aimed to investigate the therapeutic potential of TQ in an established murine syngeneic model of ovarian cancer.MethodsID8-NGL mouse ovarian cancer cells stably expressing an NF-κB reporter transgene were injected intra-peritoneally into C57BL/6 mice, and mice were treated with TQ or vehicle for 10 or 30 days. TQ was combined with the macrophage depleting drug, liposomal clodronate, in selected experiments. Effects on peritoneal tumor burden were measured by volume of ascites, number of peritoneal implants and mesenteric tumor mass. NF-κB reporter activity and markers of proliferation and apoptosis were measured in tumors and in confirmatory in vitro experiments. Protein or mRNA expression of M1 (anti-tumor) and M2 (pro-tumor) macrophage markers, and soluble cytokine profiles, were examined from harvested ascites fluid, peritoneal lavages and/or tumor sections. 2-tailed Mann–Whitney tests were used for measuring differences between groups in in vivo experiments.ResultsConsistent with its effects in vitro, TQ reduced proliferation and increased apoptosis in ID8-NGL tumors after 10 and 30 day treatment. Prolonged TQ treatment did not significantly alter tumor number or mass compared to vehicle, but rather exerted an overall deleterious effect by stimulating ascites formation. Increased ascites was accompanied by elevated NF-κB activity in tumors and macrophages, increased pro-tumor M2 macrophages and expression of pro-tumorigenic soluble factors such as VEGF in ascites fluid, and increased tumor infiltration of M2 macrophages. In contrast, a 10 day exposure to TQ produced no ascites, and reduced tumor NF-κB activity, M2 macrophages and soluble VEGF levels. Peritoneal macrophage depletion by clodronate significantly reduced tumor burden. However, TQ-stimulated ascites was further enhanced by co-treatment with clodronate, with macrophages present overwhelmingly of the M2 phenotype.ConclusionsOur findings show that pro-tumorigenic microenvironmental effects limited the efficacy of TQ in a syngeneic mouse model of ovarian cancer, and provide caution regarding its potential use in clinical trials in ovarian cancer patients.Electronic supplementary materialThe online version of this article (doi:10.1186/s12943-015-0463-5) contains supplementary material, which is available to authorized users.

Cancer bronchique et inflammation

Tumor microenvironment consists in immune and inflammatory response cells, fibroblasts and endothelial cells. Innate immunity induces inflammation and is the first non-specific line of defense against pathogens or “transformed” cells. It consists mainly of mast cells, macrophages, neutrophils and natural killer cells (NK). Chronic inflammation is associated with cancer. Many chronic inflammatory diseases are associated with an increased risk of cancer. Regarding lung cancer, chronic inflammation seen in COPD, emphysema or idiopathic pulmonary fibrosis is associated with the development of lung cancer. In this article, we will review the pro and anti-tumor effects of inflammation related to the innate immune system in lung cancer. The specific immune system is described in another chapter. During tumor progression, cancer cells will be able to use and/or bypass the signals from the inflammatory cells to promote tumor proliferation, tissue invasion and metastasis. No therapeutic agents that specifically target inflammation are available. Several strategies are being studied to target innate immunity: 1) stimulate the induction of cytotoxic M1 macrophages or natural killer cells NK, 2) limit the induction of pro-tumor M2 macrophages or neutrophils, 3) block growth factors or secreted cytokines.