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Jeffrey W Pollard - One of the best experts on this subject based on the ideXlab platform.
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abstract pr17 ccl2 induced chemokine cascade promotes breast cancer metastasis via retention of metastasis associated macrophages
2016Co-Authors: Takanori Kitamura, Jeffrey W PollardAbstract:Breast cancer is a leading cause of cancer death in women largely due to metastasis to the bone and lung. In an experimental model of breast cancer lung metastasis, macrophages characterized as F4/80 + CD11b + Ly6C high accumulate in the lung and directly contact with disseminating cancer cells within 48 hours post-tumor injection, which promotes extravasation and metastatic outgrowth of cancer cells. We have reported that these metastasis-associated macrophages (MAMs) originate from circulating inflammatory monocytes (IMs) recruited by CC-chemokine ligand 2 (CCL2), and that anti-CCL2 antibody treatments reduce the numbers of MAMs and metastatic foci. These results indicate that the CCL2-CCR2 axis plays an important role in metastatic seeding of breast cancer cells via recruitment of IMs. Although CCL2 is known as a monocyte chemoattractant, it also promotes phagocytosis, survival, and polarization of myeloid cells. Furthermore, the pro-metastatic CD11b + MAMs express a much higher level of CCR2 compared with CD11c + pulmonary resident macrophages that are not involved in breast cancer metastasis. We thus hypothesized that CCL2-CCR2 axis can also regulate pro-metastatic functions of MAMs by modulating their gene expression. To identify potential downstream targets of CCR2 signaling in MAMs, we compared their gene expression profile with that of resident macrophages in normal lung, and identified that CCL3 gene expression was increased in MAMs. By real-time PCR, we confirmed that MAMs expressed 10-fold higher Ccl3 mRNA compared with either circulating IMs or resident macrophages in the lung. Interestingly, the Ccl3 level in MAMs was significantly suppressed by in vivo treatment with anti-CCL2 antibody. Consistently, recombinant CCL2 can increase CCL3 secretion from wild type but not Ccr2 deficient macrophages in vitro, indicating that CCL2 can increase CCL3 expression in macrophages. To investigate the roles of CCL3 signaling in metastasis we intravenously injected mouse breast cancer cells into mice which blood cells lack CCL3 or its receptor CCR1, and found that loss of Ccl3 or Ccr1 significantly reduced the number of lung metastasis foci, as well as the number of MAMs accumulated in tumor-challenged lung within 24 hours. We also found that adoptive transfer of wild type IMs increased the reduced number of lung metastasis foci in Ccl3 deficient mice, suggesting that CCL3 secretion from IMs/MAMs can promote metastatic seeding of breast cancer cells by enhancing the early accumulation of MAMs via CCR1. To investigate how CCR1 promotes MAM accumulation, we injected fluorescently labeled wild type or Ccr1 / IMs into mice with lung metastasis. Although labeled monocytes from both genotypes infiltrated into the lung to a similar extent after 18 hours, there were significantly fewer Ccr1 / cells than wild type cells by 42 hours, indicating that activation of CCR1 signaling promotes retention of MAMs in the metastatic lung. Because most cancer cells extravasate within 48 hours post-injection and interact with MAMs in the lung, we hypothesized that the CCL3-CCR1 axis might enhance MAM retention through regulating the interaction between cancer cells and MAMs. We then cultured fluorescent macrophages on matrigel with cancer cells and tracked them for 24 hours by microscopy. Although majority of wild type macrophages were retained at the same position once they attached to cancer cells, Ccl3 / or Ccr1 / macrophages more frequently detached from cancer cells and moved around dishes, suggesting that the CCL3-CCR1 axis can enhance macrophage-cancer cell interaction which arrests the macrophages. These findings collectively indicate that the CCL2-triggered chemokine cascade in macrophages promotes metastatic seeding of breast cancer cells and is a potential target to prevent metastatic disease. Citation Format: Takanori Kitamura, Jeffrey W. Pollard. CCL2-induced chemokine cascade promotes breast cancer metastasis via retention of metastasis-associated macrophages. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Metastasis; 2015 Nov 30-Dec 3; Austin, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(7 Suppl):Abstract nr PR17.
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ccl2 induced chemokine cascade promotes breast cancer metastasis by enhancing retention of metastasis associated macrophages
2015Co-Authors: Takanori Kitamura, Jeffrey W Pollard, Binzhi Qian, Daniel Soong, Luca Cassetta, Gael Sugano, Yu Kato, Jiufeng LiAbstract:Pulmonary metastasis of breast cancer cells is promoted by a distinct population of macrophages, metastasis-associated macrophages (MAMs), which originate from inflammatory monocytes (IMs) recruited by the CC-chemokine ligand 2 (CCL2). We demonstrate here that, through activation of the CCL2 receptor CCR2, the recruited MAMs secrete another chemokine ligand CCL3. Genetic deletion of CCL3 or its receptor CCR1 in macrophages reduces the number of lung metastasis foci, as well as the number of MAMs accumulated in tumor-challenged lung in mice. Adoptive transfer of WT IMs increases the reduced number of lung metastasis foci in Ccl3 deficient mice. Mechanistically, Ccr1 deficiency prevents MAM retention in the lung by reducing MAM–cancer cell interactions. These findings collectively indicate that the CCL2-triggered chemokine cascade in macrophages promotes metastatic seeding of breast cancer cells thereby amplifying the pathology already extant in the system. These data suggest that inhibition of CCR1, the distal part of this signaling relay, may have a therapeutic impact in metastatic disease with lower toxicity than blocking upstream targets.
Takanori Kitamura - One of the best experts on this subject based on the ideXlab platform.
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abstract pr17 ccl2 induced chemokine cascade promotes breast cancer metastasis via retention of metastasis associated macrophages
2016Co-Authors: Takanori Kitamura, Jeffrey W PollardAbstract:Breast cancer is a leading cause of cancer death in women largely due to metastasis to the bone and lung. In an experimental model of breast cancer lung metastasis, macrophages characterized as F4/80 + CD11b + Ly6C high accumulate in the lung and directly contact with disseminating cancer cells within 48 hours post-tumor injection, which promotes extravasation and metastatic outgrowth of cancer cells. We have reported that these metastasis-associated macrophages (MAMs) originate from circulating inflammatory monocytes (IMs) recruited by CC-chemokine ligand 2 (CCL2), and that anti-CCL2 antibody treatments reduce the numbers of MAMs and metastatic foci. These results indicate that the CCL2-CCR2 axis plays an important role in metastatic seeding of breast cancer cells via recruitment of IMs. Although CCL2 is known as a monocyte chemoattractant, it also promotes phagocytosis, survival, and polarization of myeloid cells. Furthermore, the pro-metastatic CD11b + MAMs express a much higher level of CCR2 compared with CD11c + pulmonary resident macrophages that are not involved in breast cancer metastasis. We thus hypothesized that CCL2-CCR2 axis can also regulate pro-metastatic functions of MAMs by modulating their gene expression. To identify potential downstream targets of CCR2 signaling in MAMs, we compared their gene expression profile with that of resident macrophages in normal lung, and identified that CCL3 gene expression was increased in MAMs. By real-time PCR, we confirmed that MAMs expressed 10-fold higher Ccl3 mRNA compared with either circulating IMs or resident macrophages in the lung. Interestingly, the Ccl3 level in MAMs was significantly suppressed by in vivo treatment with anti-CCL2 antibody. Consistently, recombinant CCL2 can increase CCL3 secretion from wild type but not Ccr2 deficient macrophages in vitro, indicating that CCL2 can increase CCL3 expression in macrophages. To investigate the roles of CCL3 signaling in metastasis we intravenously injected mouse breast cancer cells into mice which blood cells lack CCL3 or its receptor CCR1, and found that loss of Ccl3 or Ccr1 significantly reduced the number of lung metastasis foci, as well as the number of MAMs accumulated in tumor-challenged lung within 24 hours. We also found that adoptive transfer of wild type IMs increased the reduced number of lung metastasis foci in Ccl3 deficient mice, suggesting that CCL3 secretion from IMs/MAMs can promote metastatic seeding of breast cancer cells by enhancing the early accumulation of MAMs via CCR1. To investigate how CCR1 promotes MAM accumulation, we injected fluorescently labeled wild type or Ccr1 / IMs into mice with lung metastasis. Although labeled monocytes from both genotypes infiltrated into the lung to a similar extent after 18 hours, there were significantly fewer Ccr1 / cells than wild type cells by 42 hours, indicating that activation of CCR1 signaling promotes retention of MAMs in the metastatic lung. Because most cancer cells extravasate within 48 hours post-injection and interact with MAMs in the lung, we hypothesized that the CCL3-CCR1 axis might enhance MAM retention through regulating the interaction between cancer cells and MAMs. We then cultured fluorescent macrophages on matrigel with cancer cells and tracked them for 24 hours by microscopy. Although majority of wild type macrophages were retained at the same position once they attached to cancer cells, Ccl3 / or Ccr1 / macrophages more frequently detached from cancer cells and moved around dishes, suggesting that the CCL3-CCR1 axis can enhance macrophage-cancer cell interaction which arrests the macrophages. These findings collectively indicate that the CCL2-triggered chemokine cascade in macrophages promotes metastatic seeding of breast cancer cells and is a potential target to prevent metastatic disease. Citation Format: Takanori Kitamura, Jeffrey W. Pollard. CCL2-induced chemokine cascade promotes breast cancer metastasis via retention of metastasis-associated macrophages. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Metastasis; 2015 Nov 30-Dec 3; Austin, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(7 Suppl):Abstract nr PR17.
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ccl2 induced chemokine cascade promotes breast cancer metastasis by enhancing retention of metastasis associated macrophages
2015Co-Authors: Takanori Kitamura, Jeffrey W Pollard, Binzhi Qian, Daniel Soong, Luca Cassetta, Gael Sugano, Yu Kato, Jiufeng LiAbstract:Pulmonary metastasis of breast cancer cells is promoted by a distinct population of macrophages, metastasis-associated macrophages (MAMs), which originate from inflammatory monocytes (IMs) recruited by the CC-chemokine ligand 2 (CCL2). We demonstrate here that, through activation of the CCL2 receptor CCR2, the recruited MAMs secrete another chemokine ligand CCL3. Genetic deletion of CCL3 or its receptor CCR1 in macrophages reduces the number of lung metastasis foci, as well as the number of MAMs accumulated in tumor-challenged lung in mice. Adoptive transfer of WT IMs increases the reduced number of lung metastasis foci in Ccl3 deficient mice. Mechanistically, Ccr1 deficiency prevents MAM retention in the lung by reducing MAM–cancer cell interactions. These findings collectively indicate that the CCL2-triggered chemokine cascade in macrophages promotes metastatic seeding of breast cancer cells thereby amplifying the pathology already extant in the system. These data suggest that inhibition of CCR1, the distal part of this signaling relay, may have a therapeutic impact in metastatic disease with lower toxicity than blocking upstream targets.
Hippokratis Kiaris - One of the best experts on this subject based on the ideXlab platform.
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induction of the mcp chemokine cluster cascade in the periphery by cancer cell derived ccl3
2017Co-Authors: Elena Farmaki, Vimala Kaza, Athanasios G Papavassiliou, Ioulia Chatzistamou, Hippokratis KiarisAbstract:The induction of localized pro-inflammatory niches in the periphery is instrumental in metastasis. In order to better understand how tumors engage distal sites and activate a pro-inflammatory response we utilized syngeneic breast cancers as a model and showed that soluble factors from the neoplastic epithelium activate the expression of the monocyte chemoattractive protein (MCP) chemokines of the mouse 11C cluster that include CCL1, Ccl2, Ccl7, Ccl8, CCL11 and CCL12. Tissues such as the lungs and the brain, that are more prone to colonization by breast cancer cells, were more sensitive to MCP cluster chemokine induction than others such as the liver. Subsequent analyses involving chemokine arrays in breast cancer cells and media followed by functional validation assays in in vitro and in vivo identified the cytokine Ccl3 as the principle mediator of the communication between the neoplastic epithelium and the peripheral tissues in terms of MCP cluster chemokine induction. Our results show that MCP chemokines are activated in peripheral tissues of breast cancer-bearing mice, by a mechanism that involves breast cancer cell-derived Ccl3. Interference with the expression of cancer cell-derived Ccl3 may find application in the management of breast cancer metastases.
Jon S Friedland - One of the best experts on this subject based on the ideXlab platform.
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multinucleate giant cells and the control of chemokine secretion in response to mycobacterium tuberculosis
2006Co-Authors: Xing Wu Zhu, Jon S FriedlandAbstract:Abstract Multinucleate giant cells (MGC) are characteristic of tuberculous granulomas, but their function is not well understood. In a comparative study, we investigated regulation of chemokine secretion by MGC generated using 5 μg/ml ConA and 1000 IU/ml IFN-γ. After 72-h differentiation of MGC cultures, CXCL8, CCL2 and CCL3 concentrations were 9540 ± 110 pg/ml, 11190 ± 2210 pg/ml and 19440 ± 440 pg/ml respectively all significantly higher than in MDM ( P M.tb stimulation of MGC, MDM and monocytes increased CXCL8 secretion. M.tb increased monocyte CCL2 secretion, whereas MGC and MDM secreted CCL2 constitutively. CXCL10 secretion was induced in M.tb -stimulated MDM and constitutive in MGC. All cell types responded to M.tb with CCL3 secretion. Monocyte chemokine secretion was associated with increased gene expression, whereas M . tb -stimulated MGC principally upregulated CCL3 gene expression. In summary, differentiating MGC express genes for and secrete chemokines which regulate cell influx to sites of infection. Established MGC will contribute to cell recruitment to granuloma, but this may not depend on exposure to the pathogen.
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multinucleate giant cells and the control of chemokine secretion in response to mycobacterium tuberculosis
2006Co-Authors: Xing Wu Zhu, Jon S FriedlandAbstract:Multinucleate giant cells (MGC) are characteristic of tuberculous granulomas, but their function is not well understood. In a comparative study, we investigated regulation of chemokine secretion by MGC generated using 5 microg/ml ConA and 1000 IU/ml IFN-gamma. After 72-h differentiation of MGC cultures, CXCL8, CCL2 and CCL3 concentrations were 9540+/-110 pg/ml, 11190+/-2210 pg/ml and 19440+/-440 pg/ml respectively all significantly higher than in MDM (P<0.01). There was associated increased chemokine gene expression. M.tb stimulation of MGC, MDM and monocytes increased CXCL8 secretion. M.tb increased monocyte CCL2 secretion, whereas MGC and MDM secreted CCL2 constitutively. CXCL10 secretion was induced in M.tb-stimulated MDM and constitutive in MGC. All cell types responded to M.tb with CCL3 secretion. Monocyte chemokine secretion was associated with increased gene expression, whereas M.tb-stimulated MGC principally upregulated CCL3 gene expression. In summary, differentiating MGC express genes for and secrete chemokines which regulate cell influx to sites of infection. Established MGC will contribute to cell recruitment to granuloma, but this may not depend on exposure to the pathogen.
Scott R Struthers - One of the best experts on this subject based on the ideXlab platform.
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differential desensitization receptor phosphorylation beta arrestin recruitment and erk1 2 activation by the two endogenous ligands for the cc chemokine receptor 7
2004Co-Authors: Trudy A Kohout, Shelby Nicholas, Stephen J. Perry, Greg J. Reinhart, Sachiko Junger, Scott R StruthersAbstract:Many members of the chemokine receptor family of G protein-coupled receptors utilize multiple endogenous ligands. However, differences between the signaling properties of multiple chemokines through a single receptor have yet to be well characterized. In this study we investigated the early signaling events of CCR7 initiated by its two endogenous ligands, CCL19 and CCL21. Both CCL19 and CCL21 induce G protein activation and calcium mobilization with equal potency. However, only activation by CCL19, not CCL21, promotes robust desensitization of endogenous CCR7 in the human T cell lymphoma cell line H9. Desensitization occurs through the induction of receptor phosphorylation and beta-arrestin recruitment (shown in HEK293 cells expressing CCR7-FLAG). The sites of CCL19-induced phosphorylation were mapped by mutating to alanines the serines and threonines found within kinase phosphorylation consensus sequences in the carboxyl terminus of CCR7. A cluster of sites, including Thr-373-376 and Ser-378 is important for CCL19-mediated phosphorylation of the receptor, whereas residues serine 356, 357, 364, and 365 are important for basal receptor phosphorylation by protein kinase C. Activation of CCR7 by both ligands leads to signaling to the ERK1/2 mitogen-activated protein kinase pathway. However, CCL19 promotes 4-fold more ERK1/2 phosphorylation than does CCL21. The mechanism by which CCL19 activates ERK1/2 was determined to be beta-arrestin-dependent, because it is reduced both by depletion of beta-arrestin-2 with small interfering RNA and by elimination of the phosphorylation sites in the tail of the receptor. Taken together, these findings demonstrate that CCL19 and CCL21 place CCR7 in functionally distinct conformations that are independent of their G protein-coupling potency: one that allows the efficient desensitization of the receptor and activation of ERK1/2, and another that is impaired in these functions.
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differential desensitization receptor phosphorylation β arrestin recruitment and erk1 2 activation by the two endogenous ligands for the cc chemokine receptor 7
2004Co-Authors: Trudy A Kohout, Stephen J. Perry, Greg J. Reinhart, Sachiko Junger, Shelby L Nicholas, Scott R StruthersAbstract:Many members of the chemokine receptor family of G protein-coupled receptors utilize multiple endogenous ligands. However, differences between the signaling properties of multiple chemokines through a single receptor have yet to be well characterized. In this study we investigated the early signaling events of CCR7 initiated by its two endogenous ligands, CCL19 and CCL21. Both CCL19 and CCL21 induce G protein activation and calcium mobilization with equal potency. However, only activation by CCL19, not CCL21, promotes robust desensitization of endogenous CCR7 in the human T cell lymphoma cell line H9. Desensitization occurs through the induction of receptor phosphorylation and beta-arrestin recruitment (shown in HEK293 cells expressing CCR7-FLAG). The sites of CCL19-induced phosphorylation were mapped by mutating to alanines the serines and threonines found within kinase phosphorylation consensus sequences in the carboxyl terminus of CCR7. A cluster of sites, including Thr-373-376 and Ser-378 is important for CCL19-mediated phosphorylation of the receptor, whereas residues serine 356, 357, 364, and 365 are important for basal receptor phosphorylation by protein kinase C. Activation of CCR7 by both ligands leads to signaling to the ERK1/2 mitogen-activated protein kinase pathway. However, CCL19 promotes 4-fold more ERK1/2 phosphorylation than does CCL21. The mechanism by which CCL19 activates ERK1/2 was determined to be beta-arrestin-dependent, because it is reduced both by depletion of beta-arrestin-2 with small interfering RNA and by elimination of the phosphorylation sites in the tail of the receptor. Taken together, these findings demonstrate that CCL19 and CCL21 place CCR7 in functionally distinct conformations that are independent of their G protein-coupling potency: one that allows the efficient desensitization of the receptor and activation of ERK1/2, and another that is impaired in these functions.
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differential desensitization receptor phosphorylation beta arrestin recruitment and erk1 2 activation by the two endogenous ligands for the cc chemokine receptor 7
2004Co-Authors: Trudy A Kohout, Shelby Nicholas, Stephen J. Perry, Greg J. Reinhart, Sachiko Junger, Scott R StruthersAbstract:Abstract Many members of the chemokine receptor family of G protein-coupled receptors utilize multiple endogenous ligands. However, differences between the signaling properties of multiple chemokines through a single receptor have yet to be well characterized. In this study we investigated the early signaling events of CCR7 initiated by its two endogenous ligands, CCL19 and CCL21. Both CCL19 and CCL21 induce G protein activation and calcium mobilization with equal potency. However, only activation by CCL19, not CCL21, promotes robust desensitization of endogenous CCR7 in the human T cell lymphoma cell line H9. Desensitization occurs through the induction of receptor phosphorylation and β-arrestin recruitment (shown in HEK293 cells expressing CCR7-FLAG). The sites of CCL19-induced phosphorylation were mapped by mutating to alanines the serines and threonines found within kinase phosphorylation consensus sequences in the carboxyl terminus of CCR7. A cluster of sites, including Thr-373-376 and Ser-378 is important for CCL19-mediated phosphorylation of the receptor, whereas residues serine 356, 357, 364, and 365 are important for basal receptor phosphorylation by protein kinase C. Activation of CCR7 by both ligands leads to signaling to the ERK1/2 mitogen-activated protein kinase pathway. However, CCL19 promotes 4-fold more ERK1/2 phosphorylation than does CCL21. The mechanism by which CCL19 activates ERK1/2 was determined to be β-arrestin-dependent, because it is reduced both by depletion of β-arrestin-2 with small interfering RNA and by elimination of the phosphorylation sites in the tail of the receptor. Taken together, these findings demonstrate that CCL19 and CCL21 place CCR7 in functionally distinct conformations that are independent of their G protein-coupling potency: one that allows the efficient desensitization of the receptor and activation of ERK1/2, and another that is impaired in these functions.