- Email: [email protected]
43 Tumour Promoting Macrophages and Immune Cells
S10
european journal of cancer 48, suppl. 5 (2012) S5–S12
as a measure of the genetic component of risk, modelling suggests a wide range of risks, for example that half of all breast cancers may occur in the 12% of women at the top end of the distribution. At present, however, the identified genetic variants can explain only about 10% (breast) to 30% (prostate) of the estimated variance, and predictive power is therefore quite poor. Risk information can be used by individuals, or applied to populations. I will discuss the potential applications of current markers, and those that might be observed in future. It is likely that current approaches will never succeed in identifying more than a minority of the genetic variation that underlies risk, and in quantifying the interactions of individual genetic variants with each other, and with the environment. I will speculate on possible ways round this problem.
Sunday 8 July 2012
17:30−19:15
Symposium
Inflammation and Microenvironment 42 Targeting Cytokine Networks in Malignancy 1
1
F. Balkwill . Barts and The London School of Medicine and Dentistry, London, United Kingdom Complex networks of inflammatory cytokines and chemokines are found in most experimental and human cancers and constitutive production of these mediators is a characteristic of many human malignant cell lines. However, the in vitro and in vivo interdependence of these cytokines, and their significance to the human cancer microenvironment, are both poorly understood. We are studying this in two human peritoneal (ovarian) cancers − high-grade serous, HGSC, and clear cell carcinoma. Three key cytokine/chemokine mediators of cancer-related inflammation, TNF, CXCL12 and IL6, are involved in an autocrine cytokine network, the ‘TNF network’ in the malignant cells. This network has paracrine actions on angiogenesis, infiltration of myeloid cells and NOTCH signalling in both murine xenografts and human ovarian tumor biopsies. Neutralising antibodies or siRNA to individual members of this TNF network reduced angiogenesis, myeloid cell infiltration and experimental peritoneal ovarian tumor growth. The dependency of network genes on TNF was demonstrated by their down regulation in tumor cells from patients with advanced ovarian cancer following the infusion of anti-TNF antibodies. Our findings define a network of inflammatory cytokine interactions that are crucial to tumor growth and validate this network as a key therapeutic target in ovarian cancer. To translate these observations to clinical practice, we focused on IL6. IL6 is a major mediator of cancer-related inflammation in several cancers and promotes tumor growth and angiogenesis as well as evasion of apoptosis. We investigated the therapeutic activity of CNTO328 (siltuximab), an anti-human IL6 antibody, in pre-clinical and clinical experiments. There was evidence for clinical activity of the anti-IL6 antibody, with one patient of eighteen treated demonstrating a partial response and seven showing disease stabilisation for up to nine months. In terms of mechanism of action, the clinical, pre-clinical and in silico experiments showed that antibodies to IL6 can have multiple actions within the tumor microenvironment in ovarian cancer including reductions in cytokine production, tumor angiogenesis and tumor macrophage infiltrate. We have now used a systems biology approach, combining data from phospho-proteomic mass spectrometry and gene expression array analysis, to define the best therapeutic targets within the TNF network network and to identify drugs that may synergise with cytokine and chemokine inhibitors. Targeting autocrine tumor-promoting networks with agents such as anticytokine antibodies has potential to synergize with chemotherapy, other targeted treatments and immunotherapies. 43 Tumour Promoting Macrophages and Immune Cells A. Mantovani1 . 1 Istituto Clinico Humanitas, University of Milan, Rozzano (Milan), Italy Macrophages are key orchestrators of chronic inflammation. They respond to microenvironmental signals with polarized genetic and functional programmes. M1 macrophages which are classically activated by microbial products and interferon-gamma are potent effector cells which kill microorganisms and tumours. In contrast, M2 cells, tune inflammation and adaptive immunity; promote cell proliferation by producing growth factors and products of the arginase pathway (ornithine and polyamines); scavenge debris by expressing scavenger receptors; promote angiogenesis, tissue remodeling and repair. M1 and M2 cells represent simplified extremes of a continuum of functional states. Available information suggests that TAM are a prototypic M2 population. M2 polarization of phagocytes sets these cells in a tissue remodeling and repair mode and orchestrate the smouldering and polarized chronic inflammation associated to established neoplasia. Recent studies have begun to address the central issue of the relationship between genetic events causing cancer and activation of protumour, smouldering, non resolving tumour-promoting
Sunday 8 July 2012
inflammation. New vistas have emerged on molecules associated with M2 or M2-like polarization and its orchestration. Macrophage polarization has emerged as a key determinant of resolution of inflammation. Reference(s) Biswas S.K. and Mantovani A. Macrophage plasticity and interaction with lymphocyte subsets: cancer as paradigm. Nat Immunol 2010: 11, 889– 896. Sica A and Mantovani A. Macrophage plasticity and polarization: in vivo veritas. J. Clin. Invest. (in press). 44 Proffered Paper: Osteopontin and Lactadherin Drive Pro-invasive Activation of Infiltrating Macrophages and Contribute to Glioma Progression B. Kaminska1 , A. Ellert-Miklaszewska1 , P. Wisniewski1 , M. Kijewska1 , M. Dabrowski1 , K. Gabrusiewicz1 , M. Lipko1 . 1 Nencki Institute of Experimental Biology, Cell Biology, Warsaw, Poland Background: Microglia/macrophages infiltrating malignant gliomas support invasion, angiogenesis, extracellular matrix remodeling and immunosuppression that contributes to glioma progression. Molecules and signaling pathways that direct macrophages toward a pro-invasive phenotype are poorly known. Material and Methods: Classical inflammation-related signaling pathways and global transcriptional responses were analyzed in primary rat microglia cultures exposed to glioma conditioned medium (GCM) or lipolysacharide (LPS). To identify factors that re-program microglia proteomic analysis of the C6 glioma secretome was performed. For functional studies siRNAs/shRNA or an integrin binding interfering peptide were used. Glioma cells stably expressing gene specific or control shRNA were generated and implanted to the striatum of Wistar rats. Tumor volume, macrophage infiltration/activation (staining for Iba1 and arginase 1) and angiogenesis (vWF staining) in tumor bearing brains were evaluated at day 15th after implantation. Quantification of gene expression in low and high grade human gliomas from the Canadian Brain Tumor Bank was performed by qPCR. Kaplan–Meier survival curves were acquired from the NCI Rembrandt depository. Results: Tumor-driven programming of microglia is not associated with induction of inflammation-related signaling and gene expression but triggers specific genomic responses with induction of Id and c-Myc transcription factors and several markers of the alternative M2 phenotype. Proteomic analysis of glioma secretome identified osteopontin (Spp1) and lactadherin (Mfge8) that activate integrin receptors and downstream focal adhesion kinase and PI3K/Akt signaling in microglial cells. It increases cell motility, phagocytosis, supports proliferation and induces specific genes. Interference with integrin binding or osteopontin or lactadherin expression block microglial activation. Glioma cells depleted of osteopontin or lactadherin form significantly smaller tumors than controls, show reduced macrophage activation and angiogenesis in vivo. The expression of SPP1 is highly up-regulated in glioblastoma multiforme samples. Kaplan–Meier survival curves showed inverse correlation between SPP1 expression and glioma patients survival. Conclusions: Osteopontin and lactadherin (highly overexpressed in gliomas) via integrin receptors augment microglia motility, phagocytosis, proliferation and induce the alternative activation. Osteopontin supports microgliadependent glioma invasion in vitro and in vivo. Supported by the grant N N301 786240. 45 Control of Tumour Progression and Metastasis by Lymphocyte-Produced Cytokines M. Karin1 . 1 University of California San Diego, Laboratory of Gene Regulation and Signal Transduction, Department of Pharmacology, La Jolla CA, USA Inflammation and immunity can intersect with tumor development in more than one way. While chronic inflammation promotes tumor development, many tumors that do not arise in the context of underlying inflammation still exhibit an inflammatory microenvironment. Furthermore, in certain cases, inflammation may act to suppress anti-tumor immunity, but it can also be used to enhance the efficacy of cancer immunotherapy. Undoubtedly, we need to learn much more about how inflammation and immunity affect tumor development. To study the pathogenic roles of tumor-elicited inflammation, we have used mouse models of prostate and breast cancers, two of the most common malignancies in men and women, respectively, which usually do not evolve in the context of underlying inflammation or infection. Yet, in both cases, we found that tumorelicited inflammation plays a key role in promoting metastatic spread and in the case of prostate cancer, it contributes to the failure of androgen ablation therapy. Interestingly, in both types of cancer, metastatogenesis depends on the accumulation of activated IkB kinase a (IKKa) in the nuclei of primary cancer cells, where it acts both as an activator of chromatin modifiers that control cell cycle progression and as a repressor of an anti-metastatic gene, called maspin. In both cases, IKKa, whose activation has also been observed in advanced human tumors, may be activated upon production within the tumor microenvironment of two members of the TNF family of cytokines:
european journal of cancer 48, suppl. 5 (2012) S5–S12
as a measure of the genetic component of risk, modelling suggests a wide range of risks, for example that half of all breast cancers may occur in the 12% of women at the top end of the distribution. At present, however, the identified genetic variants can explain only about 10% (breast) to 30% (prostate) of the estimated variance, and predictive power is therefore quite poor. Risk information can be used by individuals, or applied to populations. I will discuss the potential applications of current markers, and those that might be observed in future. It is likely that current approaches will never succeed in identifying more than a minority of the genetic variation that underlies risk, and in quantifying the interactions of individual genetic variants with each other, and with the environment. I will speculate on possible ways round this problem.
Sunday 8 July 2012
17:30−19:15
Symposium
Inflammation and Microenvironment 42 Targeting Cytokine Networks in Malignancy 1
1
F. Balkwill . Barts and The London School of Medicine and Dentistry, London, United Kingdom Complex networks of inflammatory cytokines and chemokines are found in most experimental and human cancers and constitutive production of these mediators is a characteristic of many human malignant cell lines. However, the in vitro and in vivo interdependence of these cytokines, and their significance to the human cancer microenvironment, are both poorly understood. We are studying this in two human peritoneal (ovarian) cancers − high-grade serous, HGSC, and clear cell carcinoma. Three key cytokine/chemokine mediators of cancer-related inflammation, TNF, CXCL12 and IL6, are involved in an autocrine cytokine network, the ‘TNF network’ in the malignant cells. This network has paracrine actions on angiogenesis, infiltration of myeloid cells and NOTCH signalling in both murine xenografts and human ovarian tumor biopsies. Neutralising antibodies or siRNA to individual members of this TNF network reduced angiogenesis, myeloid cell infiltration and experimental peritoneal ovarian tumor growth. The dependency of network genes on TNF was demonstrated by their down regulation in tumor cells from patients with advanced ovarian cancer following the infusion of anti-TNF antibodies. Our findings define a network of inflammatory cytokine interactions that are crucial to tumor growth and validate this network as a key therapeutic target in ovarian cancer. To translate these observations to clinical practice, we focused on IL6. IL6 is a major mediator of cancer-related inflammation in several cancers and promotes tumor growth and angiogenesis as well as evasion of apoptosis. We investigated the therapeutic activity of CNTO328 (siltuximab), an anti-human IL6 antibody, in pre-clinical and clinical experiments. There was evidence for clinical activity of the anti-IL6 antibody, with one patient of eighteen treated demonstrating a partial response and seven showing disease stabilisation for up to nine months. In terms of mechanism of action, the clinical, pre-clinical and in silico experiments showed that antibodies to IL6 can have multiple actions within the tumor microenvironment in ovarian cancer including reductions in cytokine production, tumor angiogenesis and tumor macrophage infiltrate. We have now used a systems biology approach, combining data from phospho-proteomic mass spectrometry and gene expression array analysis, to define the best therapeutic targets within the TNF network network and to identify drugs that may synergise with cytokine and chemokine inhibitors. Targeting autocrine tumor-promoting networks with agents such as anticytokine antibodies has potential to synergize with chemotherapy, other targeted treatments and immunotherapies. 43 Tumour Promoting Macrophages and Immune Cells A. Mantovani1 . 1 Istituto Clinico Humanitas, University of Milan, Rozzano (Milan), Italy Macrophages are key orchestrators of chronic inflammation. They respond to microenvironmental signals with polarized genetic and functional programmes. M1 macrophages which are classically activated by microbial products and interferon-gamma are potent effector cells which kill microorganisms and tumours. In contrast, M2 cells, tune inflammation and adaptive immunity; promote cell proliferation by producing growth factors and products of the arginase pathway (ornithine and polyamines); scavenge debris by expressing scavenger receptors; promote angiogenesis, tissue remodeling and repair. M1 and M2 cells represent simplified extremes of a continuum of functional states. Available information suggests that TAM are a prototypic M2 population. M2 polarization of phagocytes sets these cells in a tissue remodeling and repair mode and orchestrate the smouldering and polarized chronic inflammation associated to established neoplasia. Recent studies have begun to address the central issue of the relationship between genetic events causing cancer and activation of protumour, smouldering, non resolving tumour-promoting
Sunday 8 July 2012
inflammation. New vistas have emerged on molecules associated with M2 or M2-like polarization and its orchestration. Macrophage polarization has emerged as a key determinant of resolution of inflammation. Reference(s) Biswas S.K. and Mantovani A. Macrophage plasticity and interaction with lymphocyte subsets: cancer as paradigm. Nat Immunol 2010: 11, 889– 896. Sica A and Mantovani A. Macrophage plasticity and polarization: in vivo veritas. J. Clin. Invest. (in press). 44 Proffered Paper: Osteopontin and Lactadherin Drive Pro-invasive Activation of Infiltrating Macrophages and Contribute to Glioma Progression B. Kaminska1 , A. Ellert-Miklaszewska1 , P. Wisniewski1 , M. Kijewska1 , M. Dabrowski1 , K. Gabrusiewicz1 , M. Lipko1 . 1 Nencki Institute of Experimental Biology, Cell Biology, Warsaw, Poland Background: Microglia/macrophages infiltrating malignant gliomas support invasion, angiogenesis, extracellular matrix remodeling and immunosuppression that contributes to glioma progression. Molecules and signaling pathways that direct macrophages toward a pro-invasive phenotype are poorly known. Material and Methods: Classical inflammation-related signaling pathways and global transcriptional responses were analyzed in primary rat microglia cultures exposed to glioma conditioned medium (GCM) or lipolysacharide (LPS). To identify factors that re-program microglia proteomic analysis of the C6 glioma secretome was performed. For functional studies siRNAs/shRNA or an integrin binding interfering peptide were used. Glioma cells stably expressing gene specific or control shRNA were generated and implanted to the striatum of Wistar rats. Tumor volume, macrophage infiltration/activation (staining for Iba1 and arginase 1) and angiogenesis (vWF staining) in tumor bearing brains were evaluated at day 15th after implantation. Quantification of gene expression in low and high grade human gliomas from the Canadian Brain Tumor Bank was performed by qPCR. Kaplan–Meier survival curves were acquired from the NCI Rembrandt depository. Results: Tumor-driven programming of microglia is not associated with induction of inflammation-related signaling and gene expression but triggers specific genomic responses with induction of Id and c-Myc transcription factors and several markers of the alternative M2 phenotype. Proteomic analysis of glioma secretome identified osteopontin (Spp1) and lactadherin (Mfge8) that activate integrin receptors and downstream focal adhesion kinase and PI3K/Akt signaling in microglial cells. It increases cell motility, phagocytosis, supports proliferation and induces specific genes. Interference with integrin binding or osteopontin or lactadherin expression block microglial activation. Glioma cells depleted of osteopontin or lactadherin form significantly smaller tumors than controls, show reduced macrophage activation and angiogenesis in vivo. The expression of SPP1 is highly up-regulated in glioblastoma multiforme samples. Kaplan–Meier survival curves showed inverse correlation between SPP1 expression and glioma patients survival. Conclusions: Osteopontin and lactadherin (highly overexpressed in gliomas) via integrin receptors augment microglia motility, phagocytosis, proliferation and induce the alternative activation. Osteopontin supports microgliadependent glioma invasion in vitro and in vivo. Supported by the grant N N301 786240. 45 Control of Tumour Progression and Metastasis by Lymphocyte-Produced Cytokines M. Karin1 . 1 University of California San Diego, Laboratory of Gene Regulation and Signal Transduction, Department of Pharmacology, La Jolla CA, USA Inflammation and immunity can intersect with tumor development in more than one way. While chronic inflammation promotes tumor development, many tumors that do not arise in the context of underlying inflammation still exhibit an inflammatory microenvironment. Furthermore, in certain cases, inflammation may act to suppress anti-tumor immunity, but it can also be used to enhance the efficacy of cancer immunotherapy. Undoubtedly, we need to learn much more about how inflammation and immunity affect tumor development. To study the pathogenic roles of tumor-elicited inflammation, we have used mouse models of prostate and breast cancers, two of the most common malignancies in men and women, respectively, which usually do not evolve in the context of underlying inflammation or infection. Yet, in both cases, we found that tumorelicited inflammation plays a key role in promoting metastatic spread and in the case of prostate cancer, it contributes to the failure of androgen ablation therapy. Interestingly, in both types of cancer, metastatogenesis depends on the accumulation of activated IkB kinase a (IKKa) in the nuclei of primary cancer cells, where it acts both as an activator of chromatin modifiers that control cell cycle progression and as a repressor of an anti-metastatic gene, called maspin. In both cases, IKKa, whose activation has also been observed in advanced human tumors, may be activated upon production within the tumor microenvironment of two members of the TNF family of cytokines: