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Sample records for human tumoral myeloid

  1. Vav promotes differentiation of human tumoral myeloid precursors

    SciTech Connect

    Bertagnolo, Valeria; Brugnoli, Federica; Mischiati, Carlo; Sereni, Alessia; Bavelloni, Alberto; Carini, Cinzia; Capitani, Silvano . E-mail: cps@unife.it

    2005-05-15

    Vav is one of the genetic markers that correlate with the differentiation of hematopoietic cells. In T and B cells, it appears crucial for both development and functions, while, in non-lymphoid hematopoietic cells, Vav seems not involved in cell maturation, but rather in the response of mature cells to agonist-dependent proliferation and phagocytosis. We have previously demonstrated that the amount and the tyrosine phosphorylation of Vav are up-regulated in both whole cells and nuclei of tumoral promyelocytes induced to granulocytic maturation by ATRA and that tyrosine-phosphorylated Vav does not display any ATRA-induced GEF activity but contributes to the regulation of PI 3-K activity. In this study, we report that Vav accumulates in nuclei of ATRA-treated APL-derived cells and that the down-modulation of Vav prevents differentiation of tumoral promyelocytes, indicating that it is a key molecule in ATRA-dependent myeloid maturation. On the other hand, the overexpression of Vav induces an increased expression of surface markers of granulocytic differentiation without affecting the maturation-related changes of the nuclear morphology. Consistent with an effect of Vav on the transcriptional machinery, array profiling shows that the inhibition of the Syk-dependent tyrosine phosphorylation of Vav reduces the number of ATRA-induced genes. Our data support the unprecedented notion that Vav plays crucial functions in the maturation process of myeloid cells, and suggest that Vav can be regarded as a potential target for the therapeutic treatment of myeloproliferative disorders.

  2. Elusive identities and overlapping phenotypes of proangiogenic myeloid cells in tumors.

    PubMed

    Coffelt, Seth B; Lewis, Claire E; Naldini, Luigi; Brown, J Martin; Ferrara, Napoleone; De Palma, Michele

    2010-04-01

    It is now established that bone marrow-derived myeloid cells regulate tumor angiogenesis. This was originally inferred from studies of human tumor biopsies in which a positive correlation was seen between the number of tumor-infiltrating myeloid cells, such as macrophages and neutrophils, and tumor microvessel density. However, unequivocal evidence was only provided once mouse models were used to examine the effects on tumor angiogenesis by genetically or pharmacologically targeting myeloid cells. Since then, identifying the exact myeloid cell types involved in this process has proved challenging because of myeloid cell heterogeneity and the expression of overlapping phenotypic markers in tumors. As a result, investigators often simply refer to them now as "bone marrow-derived myeloid cells." Here we review the findings of various attempts to phenotype the myeloid cells involved and discuss the therapeutic implications of correctly identifying-and thus being able to target-this proangiogenic force in tumors. PMID:20167863

  3. Elusive Identities and Overlapping Phenotypes of Proangiogenic Myeloid Cells in Tumors

    PubMed Central

    Coffelt, Seth B.; Lewis, Claire E.; Naldini, Luigi; Brown, J. Martin; Ferrara, Napoleone; De Palma, Michele

    2010-01-01

    It is now established that bone marrow–derived myeloid cells regulate tumor angiogenesis. This was originally inferred from studies of human tumor biopsies in which a positive correlation was seen between the number of tumor-infiltrating myeloid cells, such as macrophages and neutrophils, and tumor microvessel density. However, unequivocal evidence was only provided once mouse models were used to examine the effects on tumor angiogenesis by genetically or pharmacologically targeting myeloid cells. Since then, identifying the exact myeloid cell types involved in this process has proved challenging because of myeloid cell heterogeneity and the expression of overlapping phenotypic markers in tumors. As a result, investigators often simply refer to them now as “bone marrow–derived myeloid cells.” Here we review the findings of various attempts to phenotype the myeloid cells involved and discuss the therapeutic implications of correctly identifying—and thus being able to target—this proangiogenic force in tumors. PMID:20167863

  4. Role of myeloid-derived suppressor cells in tumor immunotherapy.

    PubMed

    Martin, François; Apetoh, Lionel; Ghiringhelli, François

    2012-01-01

    Myeloid-derived suppressor cells (MDSCs) are immature myeloid cells that infiltrate human and experimental tumors and strongly inhibit anticancer immune response directly or by inducing regulatory T-lymphocyte activity. Consequently, MDSCs are important actors of cancer-induced immune tolerance and a major obstacle to efficiency of cancer immunotherapy. Several means of preventing MDSCs accumulation or inhibiting their immunosuppressive effect were recently discovered in cancer-bearing hosts, contributing to restoring antitumor immunity and consequently to control of tumor growth. In experimental tumor models, targeting MDSCs can enhance the effects of active or passive immunotherapy. While similar effects have not yet been noted in cancer-bearing patients, recent preclinical findings demonstrating that the selective toxicity of conventional chemotherapies such as gemcitabine and 5-fluorouracil on MDSCs might contribute to their anticancer effect provide impetus to pursue investigations to unravel novel therapeutics that target MDSCs in humans. PMID:22150000

  5. Tumor-induced myeloid deviation: when myeloid-derived suppressor cells meet tumor-associated macrophages

    PubMed Central

    Ugel, Stefano; De Sanctis, Francesco; Mandruzzato, Susanna; Bronte, Vincenzo

    2015-01-01

    The generation of an inflammatory environment is favorable and often decisive for the growth of both primary tumors and metastases. Tumor cells either express membrane molecules or release tumor-derived soluble factors able to alter myelopoiesis. Tumor-reprogrammed myeloid cells not only create a tolerogenic environment by blocking T cell functions and proliferation, but also directly drive tumor growth by promoting cancer stemness, angiogenesis, stroma deposition, epithelial-to-mesenchymal transition, and metastasis formation. In this Review, we discuss the interplay between immunosuppressive and protumoral myeloid cells and detail their immune-regulatory mechanisms, the molecular pathways involved in their differentiation, as well as their potential role as prognostic and diagnostic biomarkers and prospective targets for innovative approaches to treat tumor-bearing hosts. PMID:26325033

  6. Myeloid cell-driven angiogenesis and immune regulation in tumors

    PubMed Central

    Rivera, Lee B.; Bergers, Gabriele

    2015-01-01

    Angiogenesis is a hallmark of cancer as its induction is indispensable to fuel an expanding tumor. The tumor microenvironment contributes to tumor vessel growth, and distinct myeloid cells recruited by the tumor have been shown to not only support angiogenesis but to foster an immune suppressive environment that supports tumor expansion and progression. Recent findings suggest that the intertwined regulation of angiogenesis and immune modulation can offer therapeutic opportunities for the treatment of cancer. Here we review the mechanisms by which distinct myeloid cell populations contribute to tumor angiogenesis, discuss current approaches in the clinic that are targeting both angiogenic and immune suppressive pathways, and highlight important areas of future research. PMID:25770923

  7. Myeloid Cells as Targets for Therapy in Solid Tumors.

    PubMed

    Cotechini, Tiziana; Medler, Terry R; Coussens, Lisa M

    2015-01-01

    It is well established that cancer development ensues based on reciprocal interactions between genomically altered neoplastic cells and diverse populations of recruited "host" cells co-opted to support malignant progression. Among the host cells recruited into tumor microenvironments, several subtypes of myeloid cells, including macrophages, monocytes, dendritic cells, and granulocytes contribute to tumor development by providing tumor-promoting factors as well as a spectrum of molecules that suppress cytotoxic activities of T lymphocytes. Based on compelling preclinical data revealing that inhibition of critical myeloid-based programs leads to tumor suppression, novel immune-based therapies and approaches are now entering the clinic for evaluation. This review discusses mechanisms underlying protumorigenic programming of myeloid cells and discusses how targeting of these has potential to attenuate solid tumor progression via the induction and of mobilization CD8 cytotoxic T cell immunity. PMID:26222088

  8. Myeloid Cells as Targets for Therapy in Solid Tumors

    PubMed Central

    Cotechini, Tiziana; Medler, Terry R.; Coussens, Lisa M.

    2016-01-01

    It is well established that cancer development ensues based on reciprocal interactions between genomically altered neoplastic cells and diverse populations of recruited “host” cells co-opted to support malignant progression. Among the host cells recruited into tumor microenvironments, several subtypes of myeloid cells, including macrophages, monocytes, dendritic cells, and granulocytes contribute to tumor development by providing tumor-promoting factors as well as a spectrum of molecules that suppress cytotoxic activities of T lymphocytes. Based on compelling preclinical data revealing that inhibition of critical myeloid-based programs leads to tumor suppression, novel immune-based therapies and approaches are now entering the clinic for evaluation. This review discusses mechanisms underlying protumorigenic programming of myeloid cells and discusses how targeting of these has potential to attenuate solid tumor progression via the induction and of mobilization CD8+ cytotoxic T cell immunity. PMID:26222088

  9. Tumor suppressor genes in myeloid differentiation and leukemogenesis.

    PubMed

    Britschgi, Christian; Fey, Martin F

    2009-03-01

    Tumor suppressor genes, such as p53, RB, the INK4-ARF family and PML, suppress malignant transformation by regulating cell cycle progression, ensuring the fidelity of DNA replication and chromosomal segregation, or by inducing apoptosis in response to potentially deleterious events. In myeloid leukemia, hematopoietic differentiation resulting from highly coordinated, stage-wise expression of myeloid transcription and soluble signaling factors is disrupted leading to a block in terminal differentiation and uncontrolled proliferation. This virtually always involves functional inactivation or genetic disruption of one or several tumor suppressor genes in order to circumvent their checkpoint control and apoptosis-inducing functions. Hence, reactivation of tumor suppressor gene function has therapeutic potential and can possibly enhance conventional cytotoxic chemotherapy. In this review, we focus on the role of different tumor suppressor genes in myeloid differentiation and leukemogenesis, and discuss implications for therapy. PMID:19284382

  10. Primary cerebellar extramedullary myeloid cell tumor mimicking oligodendroglioma.

    PubMed

    Ho, D M; Wong, T T; Guo, W Y; Chang, K P; Yen, S H

    1997-10-01

    Extramedullary myeloid cell tumors (EMCTs) are tumors consisting of immature cells of the myeloid series that occur outside the bone marrow. Most of them are associated with acute myelogenous leukemia or other myeloproliferative disorders, and a small number occur as primary lesions, i.e., are not associated with hematological disorders. Occurrence inside the cranium is rare, and there has been only one case of primary EMCT involving the cerebellum reported in the literature. The case we report here is a blastic EMCT occurring in the cerebellum of a 3-year-old boy who had no signs of leukemia or any hematological disorder throughout the entire course. The cerebellar tumor was at first misdiagnosed as an "oligodendroglioma" because of the uniformity and "fried egg" artifact of the tumor cells. The tumor disappeared during chemotherapy consisting of 12 treatments. However, it recurred and metastasized to the cerebrospinal fluid (CSF) shortly after the therapy was completed. A diagnosis of EMCT was suspected because of the presence of immature myeloid cells in the CSF, and was confirmed by anti-myeloperoxidase and anti-lysozyme immunoreactivity of the cerebellar tumor. The patient succumbed 1 year and 3 months after the first presentation of the disease. PMID:9341943

  11. Sunitinib pretreatment improves tumor-infiltrating lymphocyte expansion by reduction in intratumoral content of myeloid-derived suppressor cells in human renal cell carcinoma.

    PubMed

    Guislain, Aurelie; Gadiot, Jules; Kaiser, Andrew; Jordanova, Ekaterina S; Broeks, Annegien; Sanders, Joyce; van Boven, Hester; de Gruijl, Tanja D; Haanen, John B A G; Bex, Axel; Blank, Christian U

    2015-10-01

    Targeted therapy with sunitinib, pazopanib or everolimus has improved treatment outcome for patients with metastatic renal cell carcinoma patients (RCC). However, despite considerable efforts in sequential or combined modalities, durable remissions are rare. Immunotherapy like cytokine therapy with interleukin-2, T cell checkpoint blockade or adoptive T cell therapies can achieve long-term benefit and even cure. This raises the question of whether combining targeted therapy with immunotherapy could also be an effective treatment option for RCC patients. Sunitinib, one of the most frequently administered therapeutics in RCC patients has been implicated in impairing T cell activation and proliferation in vitro. In this work, we addressed whether this notion holds true for expansion of tumor-infiltrating lymphocytes (TILs) in sunitinib-treated patients. We compared resected primary RCC tumor material of patients pretreated with sunitinib with resection specimen from sunitinib-naïve patients. We found improved TIL expansion from sunitinib-pretreated tumor digests. These TIL products contained more PD-1 expressing TIL, while the regulatory T cell infiltration was not altered. The improved TIL expansion was associated with reduced intratumoral myeloid-derived suppressor cell (MDSC) content. Depletion of MDSCs from sunitinib-naïve RCC tissue-digest improved TIL expansion, proving the functional relevance of the MDSC alteration by sunitinib. Our in vivo results do not support previous in vitro observations of sunitinib inhibiting T cell function, but do provide a possible rationale for the combination of sunitinib with immunotherapy. PMID:26105626

  12. CCL9 Induced by TGFβ Signaling in Myeloid Cells Enhances Tumor Cell Survival in the Premetastatic Organ.

    PubMed

    Yan, Hangyi H; Jiang, Jian; Pang, Yanli; Achyut, B R; Lizardo, Michael; Liang, Xinhua; Hunter, Kent; Khanna, Chand; Hollander, Christine; Yang, Li

    2015-12-15

    Tumor cell survival in the hostile distant organ is a rate-limiting step in cancer metastasis. Bone marrow-derived myeloid cells can form a premetastatic niche and provide a tumor-promoting microenvironment. However, it is unclear whether these myeloid cells in the premetastatic site have any direct effect on tumor cell survival. Here, we report that chemokine CCL9 was highly induced in Gr-1(+)CD11b(+) immature myeloid cells and in premetastatic lung in tumor-bearing mice. Knockdown of CCL9 in myeloid cells decreased tumor cell survival and metastasis. Importantly, CCL9 overexpression in myeloid cells lacking TGFβ signaling rescued the tumor metastasis defect observed in mice with myeloid-specific Tgfbr2 deletion. The expression level of CCL23, the human orthologue for CCL9, in peripheral blood mononuclear cells correlated with progression and survival of cancer patients. Our study demonstrates that CCL9 could serve as a good candidate for anti-metastasis treatment by targeting the rate-limiting step of cancer cell survival. In addition, targeting CCL9 may avoid the adverse effects of TGFβ-targeted therapy. PMID:26483204

  13. CSF1-ETS2-induced microRNA in myeloid cells promote metastatic tumor growth.

    PubMed

    Mathsyaraja, H; Thies, K; Taffany, D A; Deighan, C; Liu, T; Yu, L; Fernandez, S A; Shapiro, C; Otero, J; Timmers, C; Lustberg, M B; Chalmers, J; Leone, G; Ostrowski, M C

    2015-07-01

    Metastasis of solid tumors is associated with poor prognosis and bleak survival rates. Tumor-infiltrating myeloid cells (TIMs) are known to promote metastasis, but the mechanisms underlying their collaboration with tumor cells remain unknown. Here, we report an oncogenic role for microRNA (miR) in driving M2 reprogramming in TIMs, characterized by the acquisition of pro-tumor and pro-angiogenic properties. The expression of miR-21, miR-29a, miR-142-3p and miR-223 increased in myeloid cells during tumor progression in mouse models of breast cancer and melanoma metastasis. Further, we show that these miRs are regulated by the CSF1-ETS2 pathway in macrophages. A loss-of-function approach utilizing selective depletion of the miR-processing enzyme Dicer in mature myeloid cells blocks angiogenesis and metastatic tumor growth. Ectopic expression of miR-21 and miR-29a promotes angiogenesis and tumor cell proliferation through the downregulation of anti-angiogenic genes such as Col4a2, Spry1 and Timp3, whereas knockdown of the miRs impedes these processes. miR-21 and miR-29a are expressed in Csf1r+ myeloid cells associated with human metastatic breast cancer, and levels of these miRs in CD115+ non-classical monocytes correlates with metastatic tumor burden in patients. Taken together, our results suggest that miR-21 and miR-29a are essential for the pro-tumor functions of myeloid cells and the CSF1-ETS2 pathway upstream of the miRs serves as an attractive therapeutic target for the inhibition of M2 remodeling of macrophages during malignancy. In addition, miR-21 and miR-29a in circulating myeloid cells may potentially serve as biomarkers to measure therapeutic efficacy of targeted therapies for CSF1 signaling. PMID:25241894

  14. Myeloid-derived suppressor cells: Cellular missiles to target tumors.

    PubMed

    Chandra, Dinesh; Gravekamp, Claudia

    2013-11-01

    While conventional anticancer therapies, including surgical resection, radiotherapy, and/or chemotherapy, are relatively efficient at eliminating primary tumors, these treatment modalities are largely ineffective against metastases. At least in part, this reflects the rather inefficient delivery of conventional anticancer agents to metastatic lesions. We have recently demonstrated that myeloid-derived suppressor cells (MDSCs) can be used as cellular missiles to selectively deliver a radioisotope-coupled attenuated variant of Listeria monocytogenes to both primary and metastatic neoplastic lesions in mice with pancreatic cancer. This novel immunotherapeutic intervention robustly inhibited tumor growth while promoting a dramatic decrease in the number of metastases. PMID:24427545

  15. The tumor microenvironment shapes lineage, transcriptional, and functional diversity of infiltrating myeloid cells.

    PubMed

    Elpek, Kutlu G; Cremasco, Viviana; Shen, Hua; Harvey, Christopher J; Wucherpfennig, Kai W; Goldstein, Daniel R; Monach, Paul A; Turley, Shannon J

    2014-07-01

    Myeloid cells play important regulatory roles within the tumor environment by directly promoting tumor progression and modulating the function of tumor-infiltrating lymphocytes, and as such, they represent a potential therapeutic target for the treatment of cancer. Although distinct subsets of tumor-associated myeloid cells have been identified, a broader analysis of the complete myeloid cell landscape within individual tumors and also across different tumor types has been lacking. By establishing the developmental and transcriptomic signatures of infiltrating myeloid cells from multiple primary tumors, we found that tumor-associated macrophages (TAM) and tumor-associated neutrophils (TAN), while present within all tumors analyzed, exhibited strikingly different frequencies, gene expression profiles, and functions across cancer types. We also evaluated the impact of anatomic location and circulating factors on the myeloid cell composition of tumors. The makeup of the myeloid compartment was determined by the tumor microenvironment rather than the anatomic location of tumor development or tumor-derived circulating factors. Protumorigenic and hypoxia-associated genes were enriched in TAMs and TANs compared with splenic myeloid-derived suppressor cells. Although all TANs had an altered expression pattern of secretory effector molecules, in each tumor type they exhibited a unique cytokine, chemokine, and associated receptor expression profile. One such molecule, haptoglobin, was uniquely expressed by 4T1 TANs and identified as a possible diagnostic biomarker for tumors characterized by the accumulation of myeloid cells. Thus, we have identified considerable cancer-specific diversity in the lineage, gene expression, and function of tumor-infiltrating myeloid cells. PMID:24801837

  16. Tumor-Induced STAT3 Signaling in Myeloid Cells Impairs Dendritic Cell Generation by Decreasing PKCβII Abundance

    PubMed Central

    Farren, Matthew R.; Carlson, Louise M.; Netherby, Colleen S.; Lindner, Inna; Li, Pui-Kai; Gabrilovich, Dmitry I.; Abrams, Scott I.; Lee, Kelvin P.

    2014-01-01

    A major mechanism by which cancers escape control by the immune system is by blocking the differentiation of myeloid cells into dendritic cells (DCs), immunostimulatory cells that activate anti-tumor T cells. Tumor-dependent activation of signal transducer and activator of transcription 3 (STAT3) signaling in myeloid progenitor cells is thought to cause this block in their differentiation. In addition, a signaling pathway through protein kinase C βII (PKCβII) is essential for the differentiation of myeloid cells into DCs. Here, we found in humans and mice that breast cancer cells substantially decreased the abundance of PKCβII in myeloid progenitor cells through a mechanism involving the enhanced activation of STAT3 signaling by soluble, tumor-derived factors (TDFs). STAT3 bound to previously undescribed negative regulatory elements within the promoter of PRKCB, which encodes PKCβII. We also found a previously undescribed counter-regulatory mechanism through which the activity of PKCβII inhibited tumor-dependent STAT3 signaling by decreasing the abundance of cell-surface receptors, such as cytokine and growth factor receptors, that are activated by TDFs. Together, these data suggest that a previously unrecognized crosstalk mechanism between the STAT3 and PKCβII signaling pathways provides the molecular basis for the tumor-induced blockade in the differentiation of myeloid cells, and suggest that enhancing PKCβII activity may be a therapeutic strategy to alleviate cancer-mediated suppression of the immune system. PMID:24550541

  17. Myeloid Leukemias and Virally Induced Lymphomas in Miniature Inbred Swine: Development of a Large Animal Tumor Model.

    PubMed

    Duran-Struuck, Raimon; Matar, Abraham J; Huang, Christene A

    2015-01-01

    The lack of a large animal transplantable tumor model has limited the study of novel therapeutic strategies for the treatment of liquid cancers. Swine as a species provide a natural option based on their similarities with humans and their already extensive use in biomedical research. Specifically, the Massachusetts General Hospital miniature swine herd retains unique genetic characteristics that facilitate the study of hematopoietic cell and solid organ transplantation. Spontaneously arising liquid cancers in these swine, specifically myeloid leukemias and B cell lymphomas, closely resemble human malignancies. The ability to establish aggressive tumor cell lines in vitro from these naturally occurring malignancies makes a transplantable tumor model a close reality. Here, we discuss our experience with myeloid and lymphoid tumors in major histocompatibility characterized miniature swine and future approaches regarding the development of a large animal transplantable tumor model. PMID:26635868

  18. Myeloid Leukemias and Virally Induced Lymphomas in Miniature Inbred Swine: Development of a Large Animal Tumor Model

    PubMed Central

    Duran-Struuck, Raimon; Matar, Abraham J.; Huang, Christene A.

    2015-01-01

    The lack of a large animal transplantable tumor model has limited the study of novel therapeutic strategies for the treatment of liquid cancers. Swine as a species provide a natural option based on their similarities with humans and their already extensive use in biomedical research. Specifically, the Massachusetts General Hospital miniature swine herd retains unique genetic characteristics that facilitate the study of hematopoietic cell and solid organ transplantation. Spontaneously arising liquid cancers in these swine, specifically myeloid leukemias and B cell lymphomas, closely resemble human malignancies. The ability to establish aggressive tumor cell lines in vitro from these naturally occurring malignancies makes a transplantable tumor model a close reality. Here, we discuss our experience with myeloid and lymphoid tumors in major histocompatibility characterized miniature swine and future approaches regarding the development of a large animal transplantable tumor model. PMID:26635868

  19. Expansion and functions of myeloid-derived suppressor cells in the tumor microenvironment.

    PubMed

    Qu, Peng; Wang, Li-Zhen; Lin, P Charles

    2016-09-28

    Myeloid derived suppressor cells (MDSCs) are a group of immature myeloid cells accumulated in most cancer patients and mouse tumor models. MDSCs suppress host immune response and concurrently promote tumor angiogenesis, thereby promote tumor growth and progression. In this review, we discuss recent progresses in expansion and activity of tumor MDSCs, and describe new findings about immunosuppressive function of different subtypes of MDSCs in cancer. We also discussed tumor angiogenic activities and pro-tumor invasion/metastatic roles of MDSCs in tumor progression. PMID:26519756

  20. Myeloid cell signatures in tumor microenvironment predicts therapeutic response in cancer

    PubMed Central

    Achyut, Bhagelu R; Arbab, Ali S

    2016-01-01

    Tumor microenvironment (TME) consists of several immune and nonimmune cell populations including tumor cells. For many decades, experimental studies have depicted profound contribution of TME toward cancer progression and metastasis development. Several therapeutic strategies have been tested against TME through preclinical studies and clinical trials. Unfortunately, most of them have shown transient effect, and have largely failed due to aggressive tumor growth and without improving survival. Solid tumors are known to have a strong myeloid component (eg, tumor-associated macrophages) in tumor development. Recent data suggest that therapeutic responses in tumor are characterized by alterations in immune cell signatures, including tumor-associated myeloid cells. Polarized tumor-associated myeloid cells (M1–M2) are critical in impairing therapeutic effect and promoting tumor growth. The present review is intended to compile all the literatures related to the emerging contribution of different populations of myeloid cells in the development of tumor and therapeutic failures. Finally, we have discussed targeting of myeloid cell populations as a combination therapy with chemo-, targeted-, or radiation therapies. PMID:27042097

  1. Loss of prolyl hydroxylase-2 in myeloid cells and T-lymphocytes impairs tumor development.

    PubMed

    Mamlouk, Soulafa; Kalucka, Joanna; Singh, Rashim Pal; Franke, Kristin; Muschter, Antje; Langer, Anika; Jakob, Christiane; Gassmann, Max; Baretton, Gustavo B; Wielockx, Ben

    2014-02-15

    The tumor microenvironment plays a pivotal role during cancer development and progression. The balance between suppressive and cytotoxic responses of the tumor immune microenvironment has been shown to have a direct effect on the final outcome in various human and experimental tumors. Recently, we demonstrated that the oxygen sensor HIF-prolyl hydroxylase-2 (PHD2) plays a detrimental role in tumor cells, stimulating systemic growth and metastasis in mice. In our current study, we show that the conditional ablation of PHD2 in the hematopoietic system also leads to reduced tumor volume, intriguingly generated by an imbalance between enhanced cell death and improved proliferation of tumor cells. This effect seems to rely on the overall downregulation of protumoral as well as antitumoral cytokines. Using different genetic approaches, we were able to confine this complex phenotype to the crosstalk of PHD2-deficient myeloid cells and T-lymphocytes. Taken together, our findings reveal a multifaceted role for PHD2 in several hematopoietic lineages during tumor development and might have important implications for the development of tumor therapies in the future. PMID:23913502

  2. Expression of the B-Cell Receptor Component CD79a on Immature Myeloid Cells Contributes to Their Tumor Promoting Effects

    PubMed Central

    Luger, Dror; Yang, Yu-an; Raviv, Asaf; Weinberg, Douglas; Banerjee, Subhadra; Lee, Min-Jung; Trepel, Jane; Yang, Li; Wakefield, Lalage M.

    2013-01-01

    The role of myeloid derived suppressor cells (MDSCs) in promoting tumorigenesis is well-established, and significant effort is being made to further characterize surface markers on MDSCs both for better diagnosis and as potential targets for therapy. Here we show that the B cell receptor adaptor molecule CD79a is unexpectedly expressed on immature bone marrow myeloid cells, and is upregulated on MDSCs generated in multiple different mouse models of metastatic but not non-metastatic cancer. CD79a on MDSCs is upregulated and activated in response to soluble factors secreted by tumor cells. Activation of CD79a on mouse MDSCs, by crosslinking with a specific antibody, maintained their immature phenotype (CD11b+Gr1+), enhanced their migration, increased their suppressive effect on T cell proliferation, and increased secretion of pro-tumorigenic cytokines such as IL-6 and CCL22. Furthermore, crosslinking CD79a on myeloid cells activated signaling through Syk, BLNK, ERK and STAT3 phosphorylation. In vivo, CD79+ myeloid cells showed enhanced ability to promote primary tumor growth and metastasis. Finally we demonstrate that CD79a is upregulated on circulating myeloid cells from lung cancer patients, and that CD79a+ myeloid cells infiltrate human breast tumors. We propose that CD79a plays a functional role in the tumor promoting effects of myeloid cells, and may represent a novel target for cancer therapy. PMID:24146823

  3. Vaccine-induced tumor regression requires a dynamic cooperation between T cells and myeloid cells at the tumor site.

    PubMed

    Thoreau, Maxime; Penny, HweiXian Leong; Tan, KarWai; Regnier, Fabienne; Weiss, Julia Miriam; Lee, Bernett; Johannes, Ludger; Dransart, Estelle; Le Bon, Agnès; Abastado, Jean-Pierre; Tartour, Eric; Trautmann, Alain; Bercovici, Nadège

    2015-09-29

    Most cancer immunotherapies under present investigation are based on the belief that cytotoxic T cells are the most important anti-tumoral immune cells, whereas intra-tumoral macrophages would rather play a pro-tumoral role. We have challenged this antagonistic point of view and searched for collaborative contributions by tumor-infiltrating T cells and macrophages, reminiscent of those observed in anti-infectious responses. We demonstrate that, in a model of therapeutic vaccination, cooperation between myeloid cells and T cells is indeed required for tumor rejection. Vaccination elicited an early rise of CD11b+ myeloid cells that preceded and conditioned the intra-tumoral accumulation of CD8+ T cells. Conversely, CD8+ T cells and IFNγ production activated myeloid cells were required for tumor regression. A 4-fold reduction of CD8+ T cell infiltrate in CXCR3KO mice did not prevent tumor regression, whereas a reduction of tumor-infiltrating myeloid cells significantly interfered with vaccine efficiency. We show that macrophages from regressing tumors can kill tumor cells in two ways: phagocytosis and TNFα release. Altogether, our data suggest new strategies to improve the efficiency of cancer immunotherapies, by promoting intra-tumoral cooperation between macrophages and T cells. PMID:26337837

  4. Vaccine-induced tumor regression requires a dynamic cooperation between T cells and myeloid cells at the tumor site

    PubMed Central

    Thoreau, Maxime; Penny, HweiXian Leong; Tan, KarWai; Regnier, Fabienne; Weiss, Julia Miriam; Lee, Bernett; Johannes, Ludger; Dransart, Estelle; Le Bon, Agnès; Abastado, Jean-Pierre; Tartour, Eric

    2015-01-01

    Most cancer immunotherapies under present investigation are based on the belief that cytotoxic T cells are the most important anti-tumoral immune cells, whereas intra-tumoral macrophages would rather play a pro-tumoral role. We have challenged this antagonistic point of view and searched for collaborative contributions by tumor-infiltrating T cells and macrophages, reminiscent of those observed in anti-infectious responses. We demonstrate that, in a model of therapeutic vaccination, cooperation between myeloid cells and T cells is indeed required for tumor rejection. Vaccination elicited an early rise of CD11b+ myeloid cells that preceded and conditioned the intra-tumoral accumulation of CD8+ T cells. Conversely, CD8+ T cells and IFNγ production activated myeloid cells were required for tumor regression. A 4-fold reduction of CD8+ T cell infiltrate in CXCR3KO mice did not prevent tumor regression, whereas a reduction of tumor-infiltrating myeloid cells significantly interfered with vaccine efficiency. We show that macrophages from regressing tumors can kill tumor cells in two ways: phagocytosis and TNFα release. Altogether, our data suggest new strategies to improve the efficiency of cancer immunotherapies, by promoting intra-tumoral cooperation between macrophages and T cells. PMID:26337837

  5. MLL3 Is a Haploinsufficient 7q Tumor Suppressor in Acute Myeloid Leukemia

    PubMed Central

    Chen, Chong; Liu, Yu; Rappaport, Amy R.; Kitzing, Thomas; Schultz, Nikolaus; Zhao, Zhen; Shroff, Aditya S.; Dickins, Ross A.; Vakoc, Christopher R.; Bradner, James E.; Stock, Wendy; LeBeau, Michelle M.; Shannon, Kevin M.; Kogan, Scott; Zuber, Johannes; Lowe, Scott W.

    2014-01-01

    SUMMARY Recurring deletions of chromosome 7 and 7q [−7/del(7q)] occur in myelodysplastic syndromes and acute myeloid leukemia (AML) and are associated with poor prognosis. However, the identity of functionally relevant tumor suppressors on 7q remains unclear. Using RNAi and CRISPR/Cas9 approaches, we show that an ~50% reduction in gene dosage of the mixed lineage leukemia 3 (MLL3) gene, located on 7q36.1, cooperates with other events occurring in −7/del(7q) AMLs to promote leukemogenesis. Mll3 suppression impairs the differentiation of HSPC. Interestingly, Mll3-suppressed leukemias, like human −7/del(7q) AMLs, are refractory to conventional chemotherapy but sensitive to the BET inhibitor JQ1. Thus, our mouse model functionally validates MLL3 as a haploinsufficient 7q tumor suppressor and suggests a therapeutic option for this aggressive disease. PMID:24794707

  6. Functional Alteration of Tumor-infiltrating Myeloid Cells in RNA Adjuvant Therapy.

    PubMed

    Seya, Tsukasa; Shime, Hiroaki; Matsumoto, Misako

    2015-08-01

    Macrophages, as well as dendritic cells (DCs), are derived from myeloid progenitor cells. Recent evidence suggests that tumor-infiltrating macrophages differ in many aspects from conventional tissue macrophages, including nature, function and markers. Tumors usually contain various myeloid lineage cells in their non-parenchymal environment. In immunotherapy for cancer, tumor cells and non-parenchymal cells are exposed to tumor-associated antigens (TAA) and tumor-cell-derived nucleic acids. In addition, a dsRNA mimic, polyinosinic:polycytidylic acid (polyI:C), exhibits strong adjuvant activity, which acts both on the immune system and tumor constituents. Herein we discuss the RNA recognition system and unique cellular output in tumor-associated myeloid cells in response to immunotherapy. We especially focus on the mechanism by which RNA adjuvant alters the tumor-supportive nature of tumor-infiltrated myeloid cells to those with tumoricidal activity. We discuss how RNA administration makes tumor cells collapse and its significance of evoking cell death signals in tumor cells and macrophages. This knowledge will be applicable to the development of an alternative immunotherapy for cancer. PMID:26168476

  7. Cimetidine suppresses lung tumor growth in mice through proapoptosis of myeloid-derived suppressor cells.

    PubMed

    Zheng, Yisheng; Xu, Meng; Li, Xiao; Jia, Jinpeng; Fan, Kexing; Lai, Guoxiang

    2013-05-01

    Cimetidine, a histamine type-2 receptor antagonist, is known to inhibit the growth of several tumors in human and animals, however the mechanism of action underlying this effect remains largely unknown. Here, in the mice model of 3LL lung tumor, cimetidine showed significant inhibition of tumor growth. However, an in vitro study demonstrated that cimetidine showed no effect on proliferation, survival, migration and invasion of 3LL cells. We found that cimetidine reduced CD11b(+)Gr-1(+) myeloid derived-suppressive cell (MDSC) accumulation in spleen, blood and tumor tissue of tumor-bearing mice. In vitro coculture assay showed that cimetidine reversed MDSC-mediated T-cell suppression, and improved IFN-γ production. Further investigation demonstrated that the NO production and arginase I expression of MDSCs were reduced, and MDSCs prone to apoptosis by cimetidine treatment. However, MDSC differentiation was not affect by cimetidine. Importantly, although histamine H2 receptor was expressed in MDSC surface, histamine could not reverse the proapoptosis of cimetidine. Moreover, famotidine also did not have this capacity. We found that cimetidine could induce Fas and FasL expression in MDSC surface, and sequentially regulate caspase-dependent apoptosis pathway. Thus, these findings revealed a novel mechanism for cimetidine to inhibit tumor via modulation of MDSC apoptosis. PMID:23220070

  8. Myeloid PTEN deficiency impairs tumor-immune surveillance via immune-checkpoint inhibition.

    PubMed

    Kuttke, M; Sahin, E; Pisoni, J; Percig, S; Vogel, A; Kraemmer, D; Hanzl, L; Brunner, J S; Paar, H; Soukup, K; Halfmann, A; Dohnal, A M; Steiner, C W; Blüml, S; Basilio, J; Hochreiter, B; Salzmann, M; Hoesel, B; Lametschwandtner, G; Eferl, R; Schmid, J A; Schabbauer, G

    2016-07-01

    Tumor-host interaction is determined by constant immune surveillance, characterized by tumor infiltration of myeloid and lymphoid cells. A malfunctioning or diverted immune response promotes tumor growth and metastasis. Recent advances had been made, by treating of certain tumor types, such as melanoma, with T-cell checkpoint inhibitors. This highlights the importance of understanding the molecular mechanisms underlying the crosstalk between tumors and their environment, in particular myeloid and lymphoid cells. Our aim was to study the contribution of the myeloid PI3K/PTEN-signaling pathway in the regulation of tumor-immune surveillance in murine models of cancer. We made use of conditional PTEN-deficient mice, which exhibit sustained activation of the PI3K-signaling axis in a variety of myeloid cell subsets such as macrophages and dendritic cells (DCs). In colitis-associated colon cancer (CAC), mice deficient in myeloid PTEN showed a markedly higher tumor burden and decreased survival. We attributed this observation to the increased presence of immune-modulatory conventional CD8α(+) DCs in the spleen, whereas other relevant myeloid cell subsets were largely unaffected. Notably, we detected enhanced surface expression of PD-L1 and PD-L2 on these DCs. As a consequence, tumoricidal T-cell responses were hampered or redirected. Taken together, our findings indicated an unanticipated role for the PI3K/PTEN-signaling axis in the functional regulation of splenic antigen-presenting cells (APCs). Our data pointed at potential, indirect, tumoricidal effects of subclass-specific PI3K inhibitors, which are currently under clinical investigation for treatment of tumors, via myeloid cell activation. PMID:27622019

  9. Myeloid PTEN deficiency impairs tumor-immune surveillance via immune-checkpoint inhibition

    PubMed Central

    Kuttke, M.; Sahin, E.; Pisoni, J.; Percig, S.; Vogel, A.; Kraemmer, D.; Hanzl, L.; Brunner, J. S.; Paar, H.; Soukup, K.; Halfmann, A.; Dohnal, A. M.; Steiner, C. W.; Blüml, S.; Basilio, J.; Hochreiter, B.; Salzmann, M.; Hoesel, B.; Lametschwandtner, G.; Eferl, R.; Schmid, J. A.; Schabbauer, G.

    2016-01-01

    ABSTRACT Tumor–host interaction is determined by constant immune surveillance, characterized by tumor infiltration of myeloid and lymphoid cells. A malfunctioning or diverted immune response promotes tumor growth and metastasis. Recent advances had been made, by treating of certain tumor types, such as melanoma, with T-cell checkpoint inhibitors. This highlights the importance of understanding the molecular mechanisms underlying the crosstalk between tumors and their environment, in particular myeloid and lymphoid cells. Our aim was to study the contribution of the myeloid PI3K/PTEN-signaling pathway in the regulation of tumor-immune surveillance in murine models of cancer. We made use of conditional PTEN-deficient mice, which exhibit sustained activation of the PI3K-signaling axis in a variety of myeloid cell subsets such as macrophages and dendritic cells (DCs). In colitis-associated colon cancer (CAC), mice deficient in myeloid PTEN showed a markedly higher tumor burden and decreased survival. We attributed this observation to the increased presence of immune-modulatory conventional CD8α+ DCs in the spleen, whereas other relevant myeloid cell subsets were largely unaffected. Notably, we detected enhanced surface expression of PD-L1 and PD-L2 on these DCs. As a consequence, tumoricidal T-cell responses were hampered or redirected. Taken together, our findings indicated an unanticipated role for the PI3K/PTEN-signaling axis in the functional regulation of splenic antigen-presenting cells (APCs). Our data pointed at potential, indirect, tumoricidal effects of subclass-specific PI3K inhibitors, which are currently under clinical investigation for treatment of tumors, via myeloid cell activation. PMID:27622019

  10. Dopamine D2 receptor agonists inhibit lung cancer progression by reducing angiogenesis and tumor infiltrating myeloid derived suppressor cells.

    PubMed

    Hoeppner, Luke H; Wang, Ying; Sharma, Anil; Javeed, Naureen; Van Keulen, Virginia P; Wang, Enfeng; Yang, Ping; Roden, Anja C; Peikert, Tobias; Molina, Julian R; Mukhopadhyay, Debabrata

    2015-01-01

    We sought to determine whether Dopamine D2 Receptor (D2R) agonists inhibit lung tumor progression and identify subpopulations of lung cancer patients that benefit most from D2R agonist therapy. We demonstrate D2R agonists abrogate lung tumor progression in syngeneic (LLC1) and human xenograft (A549) orthotopic murine models through inhibition of tumor angiogenesis and reduction of tumor infiltrating myeloid derived suppressor cells. Pathological examination of human lung cancer tissue revealed a positive correlation between endothelial D2R expression and tumor stage. Lung cancer patients with a smoking history exhibited greater levels of D2R in lung endothelium. Our results suggest D2R agonists may represent a promising individualized therapy for lung cancer patients with high levels of endothelial D2R expression and a smoking history. PMID:25226814

  11. Dopamine D2 Receptor Agonists Inhibit Lung Cancer Progression by Reducing Angiogenesis and Tumor Infiltrating Myeloid Derived Suppressor Cells

    PubMed Central

    Hoeppner, Luke H.; Wang, Ying; Sharma, Anil; Javeed, Naureen; Van Keulen, Virginia P.; Wang, Enfeng; Yang, Ping; Roden, Anja C.; Peikert, Tobias; Molina, Julian R.; Mukhopadhyay, Debabrata

    2014-01-01

    We sought to determine whether Dopamine D2 Receptor (D2R) agonists inhibit lung tumor progression and identify subpopulations of lung cancer patients that benefit most from D2R agonist therapy. We demonstrate D2R agonists abrogate lung tumor progression in syngeneic (LLC1) and human xenograft (A549) orthotopic murine models through inhibition of tumor angiogenesis and reduction of tumor infiltrating myeloid derived suppressor cells. Pathological examination of human lung cancer tissue revealed a positive correlation between endothelial D2R expression and tumor stage. Lung cancer patients with a smoking history exhibited greater levels of D2R in lung endothelium. Our results suggest D2R agonists may represent a promising individualized therapy for lung cancer patients with high levels of endothelial D2R expression and a smoking history. PMID:25226814

  12. The influence of myeloid-derived suppressor cells on angiogenesis and tumor growth after cancer surgery.

    PubMed

    Wang, Jun; Su, Xiaosan; Yang, Liu; Qiao, Fei; Fang, Yu; Yu, Lu; Yang, Qian; Wang, Yiyin; Yin, Yanfeng; Chen, Rui; Hong, Zhipeng

    2016-06-01

    While myeloid-derived suppressor cells (MDSCs) have been reported to participate in the promotion of angiogenesis and tumor growth, little is known about their presence and function during perioperative period. Here, we demonstrated that human MDSCs expressing CD11b(+), CD33(+) and HLA-DR(-) significantly increased in lung cancer patients after thoracotomy. CD11b(+) CD33(+) HLA-DR(-) MDSCs isolated 24 hr after surgery from lung cancer patients were more efficient in promoting angiogenesis and tumor growth than MDSCs isolated before surgical operation in allograft tumor model. In addition, CD11b(+) CD33(+) HLA-DR(-) MDSCs produced high levels of MMP-9. Using an experimental lung metastasis mouse model, we demonstrated that the numbers of metastases on lung surface and Gr-1(+) CD11b(+) MDSCs at postoperative period were enhanced in proportion to the degree of surgical manipulation. We also examined that syngeneic bone marrow mesenchymal stem cells (BMSCs) significantly inhibited the induction and proliferation of Gr-1(+) CD11b(+) MDSCs and further prevented lung metastasis formation in the mice undergoing laparotomy. Taken together, our results suggest that postoperatively induced MDSCs were qualified with potent proangiogenic and tumor-promotive ability and this cell population should be considered as a target for preventing postoperative tumor metastasis. PMID:26756887

  13. Wilms tumor 1 mutations in the pathogenesis of acute myeloid leukemia

    PubMed Central

    Rampal, Raajit; Figueroa, Maria E.

    2016-01-01

    Wilms tumor 1 (WT1) has long been implicated in acute myeloid leukemia. It has been described to be both overexpressed and mutated in different forms of acute myeloid leukemia, and overexpression has been reported to play a prognostic role in this disease. However, the precise mechanism through which WT1 may play a role in leukemogenesis has remained elusive. In recent years, new evidence has emerged that points towards a novel role of WT1 mutations in the deregulation of epigenetic programs in leukemic cells through its interaction with TET proteins. Herein we review the current status of the field and its therapeutic and prognostic implications in acute myeloid leukemia. PMID:27252512

  14. Myeloid cell TRAF3 regulates immune responses and inhibits inflammation and tumor development in mice.

    PubMed

    Lalani, Almin I; Moore, Carissa R; Luo, Chang; Kreider, Benjamin Z; Liu, Yan; Morse, Herbert C; Xie, Ping

    2015-01-01

    Myeloid cells, including granulocytes, monocytes, macrophages, and dendritic cells, are crucial players in innate immunity and inflammation. These cells constitutively or inducibly express a number of receptors of the TNFR and TLR families, whose signals are transduced by TNFR-associated factor (TRAF) molecules. In vitro studies showed that TRAF3 is required for TLR-induced type I IFN production, but the in vivo function of TRAF3 in myeloid cells remains unknown. In this article, we report the generation and characterization of myeloid cell-specific TRAF3-deficient (M-TRAF3(-/-)) mice, which allowed us to gain insights into the in vivo functions of TRAF3 in myeloid cells. We found that TRAF3 ablation did not affect the maturation or homeostasis of myeloid cells in young adult mice, even though TRAF3-deficient macrophages and neutrophils exhibited constitutive NF-κB2 activation. However, in response to injections with LPS (a bacterial mimic) or polyinosinic-polycytidylic acid (a viral mimic), M-TRAF3(-/-) mice exhibited an altered profile of cytokine production. M-TRAF3(-/-) mice immunized with T cell-independent and -dependent Ags displayed elevated T cell-independent IgG3 and T cell-dependent IgG2b responses. Interestingly, 15- to 22-mo-old M-TRAF3(-/-) mice spontaneously developed chronic inflammation or tumors, often affecting multiple organs. Taken together, our findings indicate that TRAF3 expressed in myeloid cells regulates immune responses in myeloid cells and acts to inhibit inflammation and tumor development in mice. PMID:25422508

  15. Ranitidine modifies myeloid cell populations and inhibits breast tumor development and spread in mice.

    PubMed

    Vila-Leahey, Ava; Oldford, Sharon A; Marignani, Paola A; Wang, Jun; Haidl, Ian D; Marshall, Jean S

    2016-07-01

    Histamine receptor 2 (H2) antagonists are widely used clinically for the control of gastrointestinal symptoms, but also impact immune function. They have been reported to reduce tumor growth in established colon and lung cancer models. Histamine has also been reported to modify populations of myeloid-derived suppressor cells (MDSCs). We have examined the impact of the widely used H2 antagonist ranitidine, on both myeloid cell populations and tumor development and spread, in three distinct models of breast cancer that highlight different stages of cancer progression. Oral ranitidine treatment significantly decreased the monocytic MDSC population in the spleen and bone marrow both alone and in the context of an orthotopic breast tumor model. H2 antagonists ranitidine and famotidine, but not H1 or H4 antagonists, significantly inhibited lung metastasis in the 4T1 model. In the E0771 model, ranitidine decreased primary tumor growth while omeprazole treatment had no impact on tumor development. Gemcitabine treatment prevented the tumor growth inhibition associated with ranitidine treatment. In keeping with ranitidine-induced changes in myeloid cell populations in non-tumor-bearing mice, ranitidine also delayed the onset of spontaneous tumor development, and decreased the number of tumors that developed in LKB1(-/-)/NIC mice. These results indicate that ranitidine alters monocyte populations associated with MDSC activity, and subsequently impacts breast tumor development and outcome. Ranitidine has potential as an adjuvant therapy or preventative agent in breast cancer and provides a novel and safe approach to the long-term reduction of tumor-associated immune suppression. PMID:27622015

  16. Ranitidine modifies myeloid cell populations and inhibits breast tumor development and spread in mice

    PubMed Central

    Vila-Leahey, Ava; Oldford, Sharon A.; Marignani, Paola A.; Wang, Jun; Haidl, Ian D.; Marshall, Jean S.

    2016-01-01

    ABSTRACT Histamine receptor 2 (H2) antagonists are widely used clinically for the control of gastrointestinal symptoms, but also impact immune function. They have been reported to reduce tumor growth in established colon and lung cancer models. Histamine has also been reported to modify populations of myeloid-derived suppressor cells (MDSCs). We have examined the impact of the widely used H2 antagonist ranitidine, on both myeloid cell populations and tumor development and spread, in three distinct models of breast cancer that highlight different stages of cancer progression. Oral ranitidine treatment significantly decreased the monocytic MDSC population in the spleen and bone marrow both alone and in the context of an orthotopic breast tumor model. H2 antagonists ranitidine and famotidine, but not H1 or H4 antagonists, significantly inhibited lung metastasis in the 4T1 model. In the E0771 model, ranitidine decreased primary tumor growth while omeprazole treatment had no impact on tumor development. Gemcitabine treatment prevented the tumor growth inhibition associated with ranitidine treatment. In keeping with ranitidine-induced changes in myeloid cell populations in non-tumor-bearing mice, ranitidine also delayed the onset of spontaneous tumor development, and decreased the number of tumors that developed in LKB1−/−/NIC mice. These results indicate that ranitidine alters monocyte populations associated with MDSC activity, and subsequently impacts breast tumor development and outcome. Ranitidine has potential as an adjuvant therapy or preventative agent in breast cancer and provides a novel and safe approach to the long-term reduction of tumor-associated immune suppression. PMID:27622015

  17. Loss of Snail2 favors skin tumor progression by promoting the recruitment of myeloid progenitors

    PubMed Central

    Villarejo, Ana; Molina-Ortiz, Patricia; Montenegro, Yenny; Moreno-Bueno, Gema; Morales, Saleta; Santos, Vanesa; Gridley, Tom; Pérez-Moreno, Mirna A.; Peinado, Héctor; Portillo, Francisco; Calés, Carmela; Cano, Amparo

    2015-01-01

    Snail2 is a zinc finger transcription factor involved in driving epithelial to mesenchymal transitions. Snail2 null mice are viable, but display defects in melanogenesis, gametogenesis and hematopoiesis, and are markedly radiosensitive. Here, using mouse genetics, we have studied the contributions of Snail2 to epidermal homeostasis and skin carcinogenesis. Snail2 −/− mice presented a defective epidermal terminal differentiation and, unexpectedly, an increase in number, size and malignancy of tumor lesions when subjected to the two-stage mouse skin chemical carcinogenesis protocol, compared with controls. Additionally, tumor lesions from Snail2 −/− mice presented a high inflammatory component with an elevated percentage of myeloid precursors in tumor lesions that was further increased in the presence of the anti-inflammatory agent dexamethasone. In vitro studies in Snail2 null keratinocytes showed that loss of Snail2 leads to a decrease in proliferation indicating a non-cell autonomous role for Snail2 in the skin carcinogenic response observed in vivo. Bone marrow (BM) cross-reconstitution assays between Snail2 wild-type and null mice showed that Snail2 absence in the hematopoietic system fully reproduces the tumor behavior of the Snail2 null mice and triggers the accumulation of myeloid precursors in the BM, blood and tumor lesions. These results indicate a new role for Snail2 in preventing myeloid precursors recruitment impairing skin chemical carcinogenesis progression. PMID:25784375

  18. mTOR masters monocytic myeloid-derived suppressor cells in mice with allografts or tumors

    PubMed Central

    Wu, Tingting; Zhao, Yang; Wang, Hao; Li, yang; Shao, Lijuan; Wang, Ruoyu; Lu, Jun; Yang, Zhongzhou; Wang, Junjie; Zhao, Yong

    2016-01-01

    CD11b+ Gr1+ myeloid-derived suppressor cells (MDSCs) play critical roles in controlling the processes of tumors, infections, autoimmunity and graft rejection. Immunosuppressive drug rapamycin (RPM), targeting on the key cellular metabolism molecule mTOR, is currently used in clinics to treat patients with allo-grafts, autoimmune diseases and tumors. However, the effect of RPM on MDSCs has not been studied. RPM significantly decreases the cell number and the immunosuppressive ability on T cells of CD11b+ Ly6Chigh monocytic MDSCs (M-MDSCs) in both allo-grafts-transplanted and tumor-bearing mice respectively. Mice with a myeloid-specific deletion of mTOR have poor M-MDSCs after grafting with allo-skin tissue or a tumor. Grafting of allo-skin or tumors significantly activates glycolysis pathways in myeloid precursor cells in bone marrow, which is inhibited by RPM or mTOR deletion. 2-deoxyglucose (2-DG), an inhibitor of the glycolytic pathway, inhibits M-MDSC differentiation from precursors, while enhancing glycolysis by metformin significantly rescues the RPM-caused deficiency of M-MDSCs. Therefore, we offer evidence supporting that mTOR is an intrinsic factor essential for the differentiation and immunosuppressive function of M-MDSCs and that these metabolism-relevant medicines may impact MDSCs-mediated immunosuppression or immune tolerance induction, which is of considerable clinical importance in treating graft rejection, autoimmune diseases and cancers. PMID:26833095

  19. Loss of Snail2 favors skin tumor progression by promoting the recruitment of myeloid progenitors.

    PubMed

    Villarejo, Ana; Molina-Ortiz, Patricia; Montenegro, Yenny; Moreno-Bueno, Gema; Morales, Saleta; Santos, Vanesa; Gridley, Tom; Pérez-Moreno, Mirna A; Peinado, Héctor; Portillo, Francisco; Calés, Carmela; Cano, Amparo

    2015-05-01

    Snail2 is a zinc finger transcription factor involved in driving epithelial to mesenchymal transitions. Snail2 null mice are viable, but display defects in melanogenesis, gametogenesis and hematopoiesis, and are markedly radiosensitive. Here, using mouse genetics, we have studied the contributions of Snail2 to epidermal homeostasis and skin carcinogenesis. Snail2 (-/-) mice presented a defective epidermal terminal differentiation and, unexpectedly, an increase in number, size and malignancy of tumor lesions when subjected to the two-stage mouse skin chemical carcinogenesis protocol, compared with controls. Additionally, tumor lesions from Snail2 (-/-) mice presented a high inflammatory component with an elevated percentage of myeloid precursors in tumor lesions that was further increased in the presence of the anti-inflammatory agent dexamethasone. In vitro studies in Snail2 null keratinocytes showed that loss of Snail2 leads to a decrease in proliferation indicating a non-cell autonomous role for Snail2 in the skin carcinogenic response observed in vivo. Bone marrow (BM) cross-reconstitution assays between Snail2 wild-type and null mice showed that Snail2 absence in the hematopoietic system fully reproduces the tumor behavior of the Snail2 null mice and triggers the accumulation of myeloid precursors in the BM, blood and tumor lesions. These results indicate a new role for Snail2 in preventing myeloid precursors recruitment impairing skin chemical carcinogenesis progression. PMID:25784375

  20. Analogue peptides for the immunotherapy of human acute myeloid leukemia.

    PubMed

    Hofmann, Susanne; Mead, Andrew; Malinovskis, Aleksandrs; Hardwick, Nicola R; Guinn, Barbara-Ann

    2015-11-01

    The use of peptide vaccines, enhanced by adjuvants, has shown some efficacy in clinical trials. However, responses are often short-lived and rarely induce notable memory responses. The reason is that self-antigens have already been presented to the immune system as the tumor develops, leading to tolerance or some degree of host tumor cell destruction. To try to break tolerance against self-antigens, one of the methods employed has been to modify peptides at the anchor residues to enhance their ability to bind major histocompatibility complex molecules, extending their exposure to the T-cell receptor. These modified or analogue peptides have been investigated as stimulators of the immune system in patients with different cancers with variable but sometimes notable success. In this review we describe the background and recent developments in the use of analogue peptides for the immunotherapy of acute myeloid leukemia describing knowledge useful for the application of analogue peptide treatments for other malignancies. PMID:26438084

  1. AZD1480 delays tumor growth in a melanoma model while enhancing the suppressive activity of myeloid-derived suppressor cells.

    PubMed

    Maenhout, Sarah K; Du Four, Stephanie; Corthals, Jurgen; Neyns, Bart; Thielemans, Kris; Aerts, Joeri L

    2014-08-30

    AZD1480 is a potent, competitive small-molecule inhibitor of JAK1/2 kinase which inhibits STAT3 phosphorylation and tumor growth. Here we investigated the effects of AZD1480 on the function of different immune cell populations in a melanoma model. When MO4 tumor-bearing mice were treated with AZD1480 we observed a strong inhibition of tumor growth as well as a prolonged survival. Moreover, a significant decrease in the percentage of myeloid-derived suppressor cells (MDSCs) was observed after treatment with AZD1480. However, AZD1480 enhanced the suppressive capacity of murine MDSCs while at the same time impairing the proliferative as well as the IFN-γ secretion capacity of murine T cells. The addition of AZD1480 to co-cultures of human MDSCs and T cells does not affect the suppressive activity of MDSCs but it does reduce the IFN-γ secretion and the proliferative capacity of T cells. We showed that although AZD1480 has the ability to delay the tumor growth of MO4 tumor-bearing mice, this drug has detrimental effects on several aspects of the immune system. These data indicate that systemic targeting of the JAK/STAT pathway by JAK1/2 inhibition can have divergent effects on tumor growth and anti-tumor immune responses. PMID:25149535

  2. AZD1480 delays tumor growth in a melanoma model while enhancing the suppressive activity of myeloid-derived suppressor cells

    PubMed Central

    Maenhout, Sarah K.; Four, Stephanie Du; Corthals, Jurgen; Neyns, Bart; Thielemans, Kris; Aerts, Joeri L.

    2014-01-01

    AZD1480 is a potent, competitive small-molecule inhibitor of JAK1/2 kinase which inhibits STAT3 phosphorylation and tumor growth. Here we investigated the effects of AZD1480 on the function of different immune cell populations in a melanoma model. When MO4 tumor-bearing mice were treated with AZD1480 we observed a strong inhibition of tumor growth as well as a prolonged survival. Moreover, a significant decrease in the percentage of myeloid-derived suppressor cells (MDSCs) was observed after treatment with AZD1480. However, AZD1480 enhanced the suppressive capacity of murine MDSCs while at the same time impairing the proliferative as well as the IFN-γ secretion capacity of murine T cells. The addition of AZD1480 to co-cultures of human MDSCs and T cells does not affect the suppressive activity of MDSCs but it does reduce the IFN-γ secretion and the proliferative capacity of T cells. We showed that although AZD1480 has the ability to delay the tumor growth of MO4 tumor-bearing mice, this drug has detrimental effects on several aspects of the immune system. These data indicate that systemic targeting of the JAK/STAT pathway by JAK1/2 inhibition can have divergent effects on tumor growth and anti-tumor immune responses. PMID:25149535

  3. Human neutrophils: Their role in cancer and relation to myeloid-derived suppressor cells.

    PubMed

    Moses, Katrin; Brandau, Sven

    2016-04-01

    Increased frequencies of peripheral blood neutrophils as well as tumor-infiltrating (associated) neutrophils (TAN) have been observed in many tumor entities. Although the most frequent cell type in the peripheral blood, neutrophils are outnumbered by other leukocyte subsets in the tumor microenvironment. Nevertheless, a number of recent meta-analyses identified TAN as well as high neutrophil-lymphocyte ratio in the blood as one of the most powerful immunologic prognostic parameters in human oncology. This clinical impact is based on an intense bidirectional crosstalk of neutrophils and tumor cells resulting in changes in neutrophil as well as tumor cell biology. These changes eventually lead to TAN equipped with various tumor promoting features, which enhance angiogenesis, cancer cell invasion and metastasis. Many of the pro-tumor features of TAN are shared with PMN-MDSC (myeloid-derived suppressor cells). Consequently, the distinction of these two cell populations is a matter of intensive debate and also specifically discussed in this article. The importance of neutrophils in cancer progression has triggered numerous efforts to therapeutically target these cells. Current strategies in this area focus on the inhibition of either TAN recruitment or pro-tumorigenic function. PMID:27067179

  4. Cytotoxic effects of high concentrations of sodium ascorbate on human myeloid cell lines.

    PubMed

    Mastrangelo, Domenico; Massai, Lauretta; Lo Coco, Francesco; Noguera, Nélida Inés; Borgia, Loredana; Fioritoni, Giuseppe; Berardi, Anna; Iacone, Antonio; Muscettola, Michela; Pelosi, Elvira; Castelli, Germana; Testa, Ugo; Di Pisa, Francesco; Grasso, Giovanni

    2015-11-01

    The effect of high doses of intravenous (sodium) ascorbate (ASC) in the treatment of cancer has been controversial although there is growing evidence that ASC in high (pharmacologic) concentrations induces dose-dependent pro-apoptotic death of tumor cells, in vitro. Very few data are available on the role of ASC in the treatment of acute myeloid leukemia (AML). Ascorbate behaves as an antioxidant at low (physiologic), and as pro-oxidant at pharmacologic, concentrations, and this may account for the differences reported in different experimental settings, when human myeloid cell lines, such as HL60, were treated with ASC. Considering the myeloid origin of HL60 cells, and previous literature reports showing that some cell lines belonging to the myeloid lineage could be sensitive to the pro-apoptotic effects of high concentrations of ASC, we investigated in more details the effects of high doses (0.5 to 7 mM) of ASC in vitro, on a variety of human myeloid cell lines including the following: HL60, U937, NB4, NB4-R4 (retinoic acid [RA]-resistant), NB4/AsR (ATO-resistant) acute promyelocytic leukemia (APL)-derived cell lines, and K562 as well as on normal CD34+ progenitors derived from human cord blood. Our results indicate that all analyzed cell lines including all-trans retinoic acid (ATRA)- and arsenic trioxide (ATO)-resistant ones are highly sensitive to the cytotoxic, pro-oxidant effects of high doses of ASC, with an average 50 % lethal concentration (LC50) of 3 mM, depending on cell type, ASC concentration, and time of exposure. Conversely, high doses of ASC neither did exert significant cytotoxic effects nor impaired the differentiation potential in cord blood (CB) CD34+ normal cells. Since plasma ASC concentrations within the millimolar (mM) range can be easily and safely reached by intravenous administration, we conclude that phase I/II clinical trials using high doses of ASC should be designed for patients with advanced/refractory AML and APL. PMID:26264692

  5. Profoundly Reduced CD1c+ Myeloid Dendritic Cell HLA-DR and CD86 Expression and Increased Tumor Necrosis Factor Production in Experimental Human Blood-Stage Malaria Infection.

    PubMed

    Loughland, Jessica R; Minigo, Gabriela; Burel, Julie; Tipping, Peta E; Piera, Kim A; Amante, Fiona H; Engwerda, Christian R; Good, Michael F; Doolan, Denise L; Anstey, Nicholas M; McCarthy, James S; Woodberry, Tonia

    2016-05-01

    Dendritic cells (DCs) are sentinels of the immune system that uniquely prime naive cells and initiate adaptive immune responses. CD1c (BDCA-1) myeloid DCs (CD1c(+) mDCs) highly express HLA-DR, have a broad Toll-like receptor (TLR) repertoire, and secrete immune modulatory cytokines. To better understand immune responses to malaria, CD1c(+) mDC maturation and cytokine production were examined in healthy volunteers before and after experimental intravenous Plasmodium falciparum infection with 150- or 1,800-parasite-infected red blood cells (pRBCs). After either dose, CD1c(+) mDCs significantly reduced HLA-DR expression in prepatent infections. Circulating CD1c(+) mDCs did not upregulate HLA-DR after pRBC or TLR ligand stimulation and exhibited reduced CD86 expression. At peak parasitemia, CD1c(+) mDCs produced significantly more tumor necrosis factor (TNF), whereas interleukin-12 (IL-12) production was unchanged. Interestingly, only the 1,800-pRBC dose caused a reduction in the circulating CD1c(+) mDC count with evidence of apoptosis. The 1,800-pRBC dose produced no change in T cell IFN-γ or IL-2 production at peak parasitemia or at 3 weeks posttreatment. Overall, CD1c(+) mDCs are compromised by P. falciparum exposure, with impaired HLA-DR and CD86 expression, and have an increased capacity for TNF but not IL-12 production. A first prepatent P. falciparum infection is sufficient to modulate CD1c(+) mDC responsiveness, likely contributing to hampered effector T cell cytokine responses and assisting parasite immune evasion. PMID:26902728

  6. Tumor regulation of myeloid-derived suppressor cell proliferation and trafficking.

    PubMed

    Younos, Ibrahim H; Dafferner, Alicia J; Gulen, Dumrul; Britton, Holly C; Talmadge, James E

    2012-07-01

    A stress response can induce myeloid progenitor cell (MPC) proliferation, mobilization, and extramedullary hematopoiesis (EMH) within lymphoid and parenchymal organs. Our studies using in vivo BrdU labeling, Ki-67 IHC staining, and carboxyfluorescein succinimidyl ester (CFSE) adoptive cell transfer revealed that spleens, rather than bone marrow (BM) and peripheral blood (PB), from 4T1 mammary tumor-bearing (TB) mice were the primary site of MPC proliferation. The resultant increase in MPCs was associated with tumor hematopoietic growth factor (GF) transcription, decreased apoptosis, as well as, prolonged survival of splenic MPCs. In naïve mice, i.v. injected CFSE-labeled MDSCs (myeloid-derived suppressor cells) initially accumulated in the lungs, while in TB mice, they rapidly sequestered in the spleen. In contrast, a few of the injected MDSCs and leukocytes arrested, proliferated, or accumulated in the marrow, tumor, or PB of TB mice. However, BrdU labeling revealed a significant demargination of proliferating splenic MPCs into the PB. In tumors, despite high GF transcript levels, we found that a high frequency of MDSCs was apoptotic. In summary, tumor growth and cytokines regulate MPC proliferation, trafficking, accumulation, apoptosis, and survival. PMID:22609473

  7. [Therapy-Related Acute Myeloid Leukemia Following Etoposide Based Chemotherapy in Germ Cell Tumor].

    PubMed

    Okumura, Yoshinaga; Oae, Masashi; Shiraishi, Yusuke; Soda, Takeshi; Kanamaru, Hiroshi; Arima, Nobuyoshi

    2016-05-01

    A 27-year-old man visited our hospital with painless swelling of the left scrotum. Hematologic studies showed the following levels of lactate dehydrogenase, 3,171 IU/l ; alpha-fetoprotein, 2.2 ng/ml ; and β- human chorionic gonadotropin, 0.4 ng/ml, and abdominal computed tomography revealed a mass of 10×8 ×4 cm in the left testis, and that of 3.5×3.0×5.0 cm in the left renal hilar lymph node, without any other metastasis. Left high inguinal orchiectomy was performed, and histopathological examination revealed mixed form with seminoma and teratoma. He was diagnosed to have a left germ cell tumor with left renal hilar lymph node metastases, pT1, N3, M0, stage II C, indicating poor prognosis with IGCCC. The patient received four cycles of chemotherapy, COMPE regimen (CDDP, VCR, MTX, PEP, VP-16 [etoposide]). After lactate dehydrogenase, alpha-fetoprotein, and β -human chorionic gonadotropin all normalized, retroperitoneal lymph node dissection was performed. Histopathological examination revealed only a mature teratoma. Two and half years later, hematologic studies showed blast transformation. Bone marrow biopsy revealed acute myeloblastic lymphoma (M2). The patient received one cycle of AraC and daunorubicin, one cycle of high dose AraC, and three cycles of AraC and mitoxantrone. After chemotherapy, he has maintained a disease-free status for 11 years. In this case, etoposide, a topoisomerase II inhibitor, was the presumed cause of therapy-related acute myeloid leukemia. After administering chemotherapeutic agents especially etoposide, it is important to check blood count periodically for a long time. PMID:27320120

  8. Curdlan blocks the immune suppression by myeloid-derived suppressor cells and reduces tumor burden.

    PubMed

    Rui, Ke; Tian, Jie; Tang, Xinyi; Ma, Jie; Xu, Ping; Tian, Xinyu; Wang, Yungang; Xu, Huaxi; Lu, Liwei; Wang, Shengjun

    2016-08-01

    Tumor-elicited immunosuppression is one of the essential mechanisms for tumor evasion of immune surveillance. It is widely thought to be one of the main reasons for the failure of tumor immunotherapy. Myeloid-derived suppressor cells (MDSCs) comprise a heterogeneous population of cells that play an important role in tumor-induced immunosuppression. These cells expand in tumor-bearing individuals and suppress T cell responses via various mechanisms. Curdlan, the linear (1 → 3)-β-glucan from Agrobacterium, has been applied in the food industry and other sectors. The anti-tumor property of curdlan has been recognized for a long time although the underlying mechanism still needs to be explored. In this study, we investigated the effect of curdlan on MDSCs and found that curdlan could promote MDSCs to differentiate into a more mature state and then significantly reduce the suppressive function of MDSCs, decrease the MDSCs in vivo and down-regulate the suppression in tumor-bearing mice, thus leading to enhanced anti-tumor immune responses. We, therefore, increase the understanding of further mechanisms by which curdlan achieves anti-tumor effects. PMID:26832917

  9. Membrane-bound human SCF/KL promotes in vivo human hematopoietic engraftment and myeloid differentiation

    PubMed Central

    Takagi, Shinsuke; Saito, Yoriko; Hijikata, Atsushi; Tanaka, Satoshi; Watanabe, Takashi; Hasegawa, Takanori; Mochizuki, Shinobu; Kunisawa, Jun; Kiyono, Hiroshi; Koseki, Haruhiko; Ohara, Osamu; Saito, Takashi; Taniguchi, Shuichi; Shultz, Leonard D.

    2012-01-01

    In recent years, advances in the humanized mouse system have led to significantly increased levels of human hematopoietic stem cell (HSC) engraftment. The remaining limitations in human HSC engraftment and function include lymphoid-skewed differentiation and inefficient myeloid development in the recipients. Limited human HSC function may partially be attributed to the inability of the host mouse microenvironment to provide sufficient support to human hematopoiesis. To address this problem, we created membrane-bound human stem cell factor (SCF)/KIT ligand (KL)–expressing NOD/SCID/IL2rgKO (hSCF Tg NSG) mice. hSCF Tg NSG recipients of human HSCs showed higher levels of both human CD45+ cell engraftment and human CD45+CD33+ myeloid development compared with NSG recipients. Expression of hSCF/hKL accelerated the differentiation of the human granulocyte lineage cells in the recipient bone marrow. Human mast cells were identified in bone marrow, spleen, and gastrointestinal tissues of the hSCF Tg NSG recipients. This novel in vivo humanized mouse model demonstrates the essential role of membrane-bound hSCF in human myeloid development. Moreover, the hSCF Tg NSG humanized recipients may facilitate investigation of in vivo differentiation, migration, function, and pathology of human mast cells. PMID:22279057

  10. Silibinin inhibits accumulation of myeloid-derived suppressor cells and tumor growth of murine breast cancer.

    PubMed

    Forghani, Parvin; Khorramizadeh, Mohammad R; Waller, Edmund K

    2014-04-01

    Myeloid-derived suppressor cells (MDSC)s increase in blood and accumulate in the tumor microenvironment of tumor-bearing animals, contributing to immune suppression in cancer. Silibinin, a natural flavonoid from the seeds of milk thistle, has been developed as an anti-inflammatory agent and supportive care agent to reduce the toxicity of cancer chemotherapy. The goals of this study were to evaluate the effect of silibinin on MDSCs in tumor-bearing mice and antitumor activity of silibinin in a mouse model of breast cancer. 4T1 luciferase-transfected mammary carcinoma cells were injected into in the mammary fat pad female BALB/c mice, and female CB17-Prkdc Scid/J mice. Silibinin treatment started on day 4 or day 14 after tumor inoculation continued every other day. Tumor growth was monitored by bioluminescent imaging (BLI) measuring total photon flux. Flow cytometry measured total leukocytes, CD11b(+) Gr-1(+) MDSC, and T cells in the blood and tumors of tumor-bearing mice. The effects of silibinin on 4T1 cell viability in vitro were measured by BLI. Treatment with silibinin increased overall survival in mice harboring tumors derived from the 4T1-luciferase breast cancer cell line, and reduced tumor volumes and numbers of CD11b(+) Gr-1(+) MDSCs in the blood and tumor, and increased the content of T cells in the tumor microenvironment. Silibinin failed to inhibit tumor growth in immunocompromised severe combined immunodeficiency mice, supporting the hypothesis that anticancer effect of silibinin is immune-mediated. The antitumor activity of silibinin requires an intact host immune system and is associated with decreased accumulation of blood and tumor-associated MDSCs. PMID:24574320

  11. BEX1 acts as a tumor suppressor in acute myeloid leukemia

    PubMed Central

    Lindblad, Oscar; Li, Tianfeng; Su, Xianwei; Sun, Jianmin; Kabir, Nuzhat N.; Levander, Fredrik; Zhao, Hui; Lu, Gang; Rönnstrand, Lars; Kazi, Julhash U.

    2015-01-01

    Acute myeloid leukemia (AML) is a heterogeneous disease of the myeloid lineage. About 35% of AML patients carry an oncogenic FLT3 mutant making FLT3 an attractive target for treatment of AML. Major problems in the development of FLT3 inhibitors include lack of specificity, poor response and development of a resistant phenotype upon treatment. Further understanding of FLT3 signaling and discovery of novel regulators will therefore help to determine additional pharmacological targets in FLT3-driven AML. In this report, we identified BEX1 as a novel regulator of oncogenic FLT3-ITD-driven AML. We showed that BEX1 expression was down-regulated in a group of AML patients carrying FLT3-ITD. Loss of BEX1 expression resulted in poor overall survival (hazard ratio, HR = 2.242, p = 0.0011). Overexpression of BEX1 in mouse pro-B and myeloid cells resulted in decreased FLT3-ITD-dependent cell proliferation, colony and tumor formation, and in increased apoptosis in vitro and in vivo. BEX1 localized to the cytosolic compartment of cells and significantly decreased FLT3-ITD-induced AKT phosphorylation without affecting ERK1/2 or STAT5 phosphorylation. Our data suggest that the loss of BEX1 expression in FLT3-ITD driven AML potentiates oncogenic signaling and leads to decreased overall survival of the patients. PMID:26046670

  12. BEX1 acts as a tumor suppressor in acute myeloid leukemia.

    PubMed

    Lindblad, Oscar; Li, Tianfeng; Su, Xianwei; Sun, Jianmin; Kabir, Nuzhat N; Levander, Fredrik; Zhao, Hui; Lu, Gang; Rönnstrand, Lars; Kazi, Julhash U

    2015-08-28

    Acute myeloid leukemia (AML) is a heterogeneous disease of the myeloid lineage. About 35% of AML patients carry an oncogenic FLT3 mutant making FLT3 an attractive target for treatment of AML. Major problems in the development of FLT3 inhibitors include lack of specificity, poor response and development of a resistant phenotype upon treatment. Further understanding of FLT3 signaling and discovery of novel regulators will therefore help to determine additional pharmacological targets in FLT3-driven AML. In this report, we identified BEX1 as a novel regulator of oncogenic FLT3-ITD-driven AML. We showed that BEX1 expression was down-regulated in a group of AML patients carrying FLT3-ITD. Loss of BEX1 expression resulted in poor overall survival (hazard ratio, HR = 2.242, p = 0.0011). Overexpression of BEX1 in mouse pro-B and myeloid cells resulted in decreased FLT3-ITD-dependent cell proliferation, colony and tumor formation, and in increased apoptosis in vitro and in vivo. BEX1 localized to the cytosolic compartment of cells and significantly decreased FLT3-ITD-induced AKT phosphorylation without affecting ERK1/2 or STAT5 phosphorylation. Our data suggest that the loss of BEX1 expression in FLT3-ITD driven AML potentiates oncogenic signaling and leads to decreased overall survival of the patients. PMID:26046670

  13. Myeloid-Derived Suppressor Cells: Critical Cells Driving Immune Suppression in the Tumor Microenvironment

    PubMed Central

    Parker, Katherine H.; Beury, Daniel W.; Ostrand-Rosenberg, Suzanne

    2015-01-01

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells that suppress innate and adaptive immunity. MDSCs are present in many disease settings; however, in cancer, they are a major obstacle for both natural antitumor immunity and immunotherapy. Tumor and host cells in the tumor microenvironment (TME) produce a myriad of pro-inflammatory mediators that activate MDSCs and drive their accumulation and suppressive activity. MDSCs utilize a variety of mechanisms to suppress T cell activation, induce other immune-suppressive cell populations, regulate inflammation in the TME, and promote the switching of the immune system to one that tolerates and enhances tumor growth. Because MDSCs are present in most cancer patients and are potent immune-suppressive cells, MDSCs have been the focus of intense research in recent years. This review describes the history and identification of MDSCs, the role of inflammation and intracellular signaling events governing MDSC accumulation and suppressive activity, immune-suppressive mechanisms utilized by MDSCs, and recent therapeutics that target MDSCs to enhance antitumor immunity. PMID:26216631

  14. CD45 Phosphatase Inhibits STAT3 Transcription Factor Activity in Myeloid Cells and Promotes Tumor-Associated Macrophage Differentiation.

    PubMed

    Kumar, Vinit; Cheng, Pingyan; Condamine, Thomas; Mony, Sridevi; Languino, Lucia R; McCaffrey, Judith C; Hockstein, Neil; Guarino, Michael; Masters, Gregory; Penman, Emily; Denstman, Fred; Xu, Xiaowei; Altieri, Dario C; Du, Hong; Yan, Cong; Gabrilovich, Dmitry I

    2016-02-16

    Recruitment of monocytic myeloid-derived suppressor cells (MDSCs) and differentiation of tumor-associated macrophages (TAMs) are the major factors contributing to tumor progression and metastasis. We demonstrated that differentiation of TAMs in tumor site from monocytic precursors was controlled by downregulation of the activity of the transcription factor STAT3. Decreased STAT3 activity was caused by hypoxia and affected all myeloid cells but was not observed in tumor cells. Upregulation of CD45 tyrosine phosphatase activity in MDSCs exposed to hypoxia in tumor site was responsible for downregulation of STAT3. This effect was mediated by the disruption of CD45 protein dimerization regulated by sialic acid. Thus, STAT3 has a unique function in the tumor environment in controlling the differentiation of MDSC into TAM, and its regulatory pathway could be a potential target for therapy. PMID:26885857

  15. Detection of human myeloid progenitor cells in a murine background.

    PubMed

    Carow, C E; Harrington, M A; Broxmeyer, H E

    1993-01-01

    Cell-mixing experiments were performed to determine whether human (hu) peripheral blood plasma would select for the growth of hu myeloid progenitor cells in vitro. Mixtures of hu male umbilical cord blood and murine (mu) female bone marrow (100% hu, 100% mu, 1.0% hu or 10% hu and 50% hu) were plated in methylcellulose cultures that contained either hu plasma or fetal bovine serum (FBS). Cultures were supplemented with recombinant (r) hu erythropoietin (Epo) alone or in combination with rhu granulocyte-macrophage colony stimulating factor (GM-CSF), rmuGM-CSF or rhu steel factor (SLF). DNA was extracted from day 14 colonies and clusters, and the polymerase chain reaction (PCR) was used to detect the hu Y-chromosome satellite DNA sequence. Results of these studies revealed that hu plasma used in combination with hu growth factors selected for the growth of hu progenitor cells. Mu cells grew in hu plasma only at high cell-plating concentrations. This selective effect was due to a heat labile factor or factors, since mu cells grew equally well in heat-inactivated hu plasma and FBS. Cells in individual progenitor cell colonies and clusters cultured in hu plasma contained hu Y-chromosome-specific DNA sequences that were detectable after PCR-mediated amplification, thus eliminating the need for time-consuming Southern transfer. This study describes a method whereby hu/immune-deficient mice can be screened rapidly for hu myeloid engraftment. These results also indicate that the hu identity of colonies and clusters cultured in hu plasma must be genetically confirmed, especially when hu cells may represent a low percentage of the total cells plated. PMID:7678088

  16. Recruitment of myeloid but not endothelial precursor cells facilitates tumor re-growth after local irradiation

    PubMed Central

    Kozin, Sergey V.; Kamoun, Walid S.; Huang, Yuhui; Dawson, Michelle R.; Jain, Rakesh K.; Duda, Dan G.

    2010-01-01

    Tumor neovascularization and growth may be promoted by recruitment of bone marrow-derived cells (BMDCs), which include endothelial precursor cells (EPCs) and “vascular modulatory” myelomonocytic (CD11b+) cells. BMDCs may also drive tumor re-growth after certain chemotherapeutic and vascular disruption treatments. In this study, we evaluated the role of BMDC recruitment in breast and lung carcinoma xenograft models after local irradiation (LI). We depleted the bone marrow by including whole body irradiation (WBI) of 6Gy as part of a total tumor dose of 21Gy, and compared the growth delay with the one achieved after LI of 21Gy. In both models, including WBI induced longer tumor growth delays. Moreover, including WBI increased lung tumor control probability by LI. Exogenous delivery of BMDCs from radiation-naïve donors partially abrogated the WBI effect. Myeloid BMDCs, primarily macrophages, rapidly accumulated in tumors after LI. Intratumoral expression of SDF-1α, a chemokine that promotes tissue retention of BMDCs, was noted 2 days after LI. Conversely, treatment with an inhibitor of SDF-1α receptor CXCR4 (AMD3100) with LI significantly delayed tumor re-growth. However, when administered starting from 5 days post-LI, AMD3100 treatment was ineffective. Lastly, with restorative bone marrow transplantation of Tie2-GFP-labeled BMDC population we observed an increased number of monocytes but not EPCs in tumors that recurred following LI. Our results suggest that an increase in intratumoral SDF-1α triggered by local irradiation recruits myelomonocyte/macrophage which promote tumor re-growth. PMID:20631066

  17. Interleukin-15-Induced CD56+ Myeloid Dendritic Cells Combine Potent Tumor Antigen Presentation with Direct Tumoricidal Potential

    PubMed Central

    Anguille, Sébastien; Lion, Eva; Tel, Jurjen; de Vries, I. Jolanda M; Couderé, Karen; Fromm, Phillip D.; Van Tendeloo, Viggo F.

    2012-01-01

    Dendritic cells (DCs) are the quintessential antigen-presenting cells of the human immune system and play a prime role in coordinating innate and adaptive immune responses, explaining the strong and still growing interest in their application for cancer immunotherapy. Much current research in the field of DC-based immunotherapy focuses on optimizing the culture conditions for in vitro DC generation in order to assure that DCs with the best possible immunogenic qualities are being used for immunotherapy. In this context, monocyte-derived DCs that are alternatively induced by interleukin-15 (IL-15 DCs) have attracted recent attention due to their superior immunostimulatory characteristics. In this study, we show that IL-15 DCs, in addition to potent tumor antigen-presenting function, possess tumoricidal potential and thus qualify for the designation of killer DCs. Notwithstanding marked expression of the natural killer (NK) cell marker CD56 on a subset of IL-15 DCs, we found no evidence of a further phenotypic overlap between IL-15 DCs and NK cells. Allostimulation and antigen presentation assays confirmed that IL-15 DCs should be regarded as bona fide myeloid DCs not only from the phenotypic but also from the functional point of view. Concerning their cytotoxic activity, we demonstrate that IL-15 DCs are able to induce apoptotic cell death of the human K562 tumor cell line, while sparing tumor antigen-specific T cells. The cytotoxicity of IL-15 DCs is predominantly mediated by granzyme B and, to a small extent, by tumor necrosis factor-α (TNF-α)-related apoptosis-inducing ligand (TRAIL) but is independent of perforin, Fas ligand and TNF-α. In conclusion, our data provide evidence of a previously unappreciated role for IL-15 in the differentiation of human monocytes towards killer DCs. The observation that IL-15 DCs have killer DC capacity lends further support to their implementation in DC-based immunotherapy protocols. PMID:23284789

  18. Anemia prevalence and treatment practice in patients with non-myeloid tumors receiving chemotherapy

    PubMed Central

    Merlini, Laura; Cartenì, Giacomo; Iacobelli, Stefano; Stelitano, Caterina; Airoldi, Mario; Balcke, Peter; Keil, Felix; Haslbauer, Ferdinand; Belton, Laura; Pujol, Beatriz

    2013-01-01

    Purpose To describe the prevalence and management of anemia in cancer patients. Methods This cross-sectional, observational survey was conducted in Italy and Austria. Centers prespecified one day, during a 4-month enrollment window, to report specific data collected during normal clinical practice for patients with non-myeloid tumors attending for chemotherapy (±radiotherapy) treatment. The primary endpoint was the prevalence of anemia as determined using a prespecified algorithm: hemoglobin (Hb) ≤10 g/dL on/within 3 days prior to visit; ongoing anemia treatment; physician diagnosis of anemia, together with ≥1 anemia symptom. Results Between November 18, 2010 and March 18, 2011, data for 1412 patients were collected (Italy n = 1130; Austria n = 282). Most patients (n = 1136; 80%) had solid tumors; 809 (57%) had received ≤3 chemotherapy cycles. The prevalence of anemia was 32% (95% confidence interval: 29.4%–34.2%); 196 patients (14%) were deemed anemic based on Hb ≤10 g/dL, 131 (9%) on ongoing anemia treatment, and 121 (9%) on physician diagnosis/anemia symptom. Overall, 1153 patients (82%) had Hb data; mean (standard deviation [SD]) Hb levels were 11.7 (1.7) g/dL. In total, 456 patients (32%) had anemia symptoms: fatigue (n = 392; 28%), depression (n = 122; 9%), and dyspnea (n = 107; 8%) were most common. Fifty-one patients (4%) had had their current chemotherapy cycle delayed due to anemia. On visit day, or ≤28 days prior, 91 (6%), 188 (13%), and 81 patients (6%) had evidence of whole blood/red blood cell transfusion, erythropoiesis-stimulating agent use, or iron use, respectively. Conclusion On the prespecified study day, one-third of patients with non-myeloid tumors undergoing chemotherapy were found to be anemic and 13% had evidence of erythropoiesis-stimulating agent use then or in the 28 days prior. PMID:23946669

  19. Interaction of Rotavirus with Human Myeloid Dendritic Cells

    PubMed Central

    Narváez, Carlos F.; Angel, Juana; Franco, Manuel A.

    2005-01-01

    We have previously shown that very few rotavirus (RV)-specific T cells that secrete gamma interferon circulate in recently infected and seropositive adults and children. Here, we have studied the interaction of RV with myeloid immature (IDC) and mature dendritic cells (MDC) in vitro. RV did not induce cell death of IDC or MDC and induced maturation of between 12 and 48% of IDC. Nonetheless, RV did not inhibit the maturation of IDC or change the expression of maturation markers on MDC. After treatment with RV, few IDC expressed the nonstructural viral protein NSP4. In contrast, a discrete productive viral infection was shown in MDC of a subset of volunteers, and between 3 and 46% of these cells expressed NSP4. RV-treated IDC secreted interleukin 6 (IL-6) (but not IL-1β, IL-8, IL-10, IL-12, tumor necrosis factor alpha, or transforming growth factor beta), and MDC released IL-6 and small amounts of IL-10 and IL-12p70. The patterns of cytokines secreted by T cells stimulated by staphylococcal enterotoxin B presented by MDC infected with RV or uninfected were comparable. The frequencies and patterns of cytokines secreted by memory RV-specific T cells evidenced after stimulation of peripheral blood mononuclear cells (PBMC) with RV were similar to those evidenced after stimulation of PBMC with RV-infected MDC. Finally, IDC treated with RV strongly stimulated naive allogeneic CD4+ T cells to secrete Th1 cytokines. Thus, although RV does not seem to be a strong maturing stimulus for DC, it promotes their capacity to prime Th1 cells. PMID:16282452

  20. Human cytomegalovirus tropism for mucosal myeloid dendritic cells

    PubMed Central

    Hertel, Laura

    2014-01-01

    SUMMARY Human CMV infections are a serious source of morbidity and mortality for immunocompromised patients and for the developing fetus. Because of this, the development of new strategies to prevent CMV acquisition and transmission is a top priority. Myeloid dendritic cells (DC) residing in the oral and nasal mucosae are among the first immune cells to encounter CMV during entry, and greatly contribute to virus dissemination, reactivation from latency, and horizontal spread. Albeit affected by the immunoevasive tactics of CMV, mucosal DC remain potent inducers of cellular and humoral immune responses against this virus. Their natural functions could thus be exploited to generate long-lasting protective immunity against CMV by vaccination via the oro-nasal mucosae. Although related, epithelial Langerhans-type DC (LC) and dermal monocyte-derived DC (MDDC) interact with CMV in dramatically different ways. While immature MDDC are fully permissive to infection, for instance, immature LC are completely resistant. Understanding these differences is essential to design innovative vaccines and new antiviral compounds to protect these cells from CMV infection in vivo. PMID:24888709

  1. Analyzing tumor heterogeneity and driver genes in single myeloid leukemia cells with SBCapSeq.

    PubMed

    Mann, Karen M; Newberg, Justin Y; Black, Michael A; Jones, Devin J; Amaya-Manzanares, Felipe; Guzman-Rojas, Liliana; Kodama, Takahiro; Ward, Jerrold M; Rust, Alistair G; van der Weyden, Louise; Yew, Christopher Chin Kuan; Waters, Jill L; Leung, Marco L; Rogers, Keith; Rogers, Susan M; McNoe, Leslie A; Selvanesan, Luxmanan; Navin, Nicholas; Jenkins, Nancy A; Copeland, Neal G; Mann, Michael B

    2016-09-01

    A central challenge in oncology is how to kill tumors containing heterogeneous cell populations defined by different combinations of mutated genes. Identifying these mutated genes and understanding how they cooperate requires single-cell analysis, but current single-cell analytic methods, such as PCR-based strategies or whole-exome sequencing, are biased, lack sequencing depth or are cost prohibitive. Transposon-based mutagenesis allows the identification of early cancer drivers, but current sequencing methods have limitations that prevent single-cell analysis. We report a liquid-phase, capture-based sequencing and bioinformatics pipeline, Sleeping Beauty (SB) capture hybridization sequencing (SBCapSeq), that facilitates sequencing of transposon insertion sites from single tumor cells in a SB mouse model of myeloid leukemia (ML). SBCapSeq analysis of just 26 cells from one tumor revealed the tumor's major clonal subpopulations, enabled detection of clonal insertion events not detected by other sequencing methods and led to the identification of dominant subclones, each containing a unique pair of interacting gene drivers along with three to six cooperating cancer genes with SB-driven expression changes. PMID:27479497

  2. Protection against HPV-16-Associated Tumors Requires the Activation of CD8+ Effector Memory T Cells and the Control of Myeloid-Derived Suppressor Cells.

    PubMed

    Diniz, Mariana O; Sales, Natiely S; Silva, Jamile R; Ferreira, Luís Carlos S

    2016-08-01

    Active anticancer immunotherapeutic approaches have been shown to induce cellular or humoral immune responses in patients, but, thus far, the observed outcomes did not ensure their recommendation for clinical use. The induction of tumor-specific CD8(+) T cells, although required for the clearance of most solid tumors, was shown to be insufficient for the development of a successful immunotherapeutic approach. The suppressive immune environment triggered by tumors, including the expansion of myeloid-derived suppressor cells (MDSC), is detrimental to the development of antitumor immune responses and precludes the generation of more promising clinical outcomes. In this work, we characterized the CD8(+) T-cell population specifically involved in the control of tumor growth and the role of MDSCs after administration of an antitumor therapeutic DNA vaccine targeting human papillomavirus type 16 (HPV-16)-associated tumors. Activation of cytotoxic high-avidity CD8(+) T cells with an effector memory phenotype was found in mice grafted with tumor cells expressing the HPV-16 oncoproteins. In addition, MDSC antibody depletion further enhanced the immunotherapeutic effects of the vaccine, resulting in the complete eradication of tumor cells. Collectively, the current results indicate that the simultaneous control of MDSCs and activation of high-avidity tumor-specific effector memory CD8(+) T cells are key features for tumor protection by immunotherapeutic approaches and deserve further testing under clinical conditions. Mol Cancer Ther; 15(8); 1920-30. ©2016 AACR. PMID:27222537

  3. Acute inflammation induces immunomodulatory effects on myeloid cells associated with anti-tumor responses in a tumor mouse model.

    PubMed

    Salem, Mohamed L; Attia, Zeinab I; Galal, Sohaila M

    2016-03-01

    Given the self nature of cancer, anti-tumor immune response is weak. As such, acute inflammation induced by microbial products can induce signals that result in initiation of an inflammatory cascade that helps activation of immune cells. We aimed to compare the nature and magnitude of acute inflammation induced by toll-like receptor ligands (TLRLs) on the tumor growth and the associated inflammatory immune responses. To induce acute inflammation in tumor-bearing host, CD1 mice were inoculated with intraperitoneal (i.p.) injection of Ehrlich ascites carcinoma (EAC) (5 × 10(5) cells/mouse), and then treated with i.p. injection on day 1, day 7 or days 1 + 7 with: (1) polyinosinic:polycytidylic (poly(I:C)) (TLR3L); (2) Poly-ICLC (clinical grade of TLR3L); (3) Bacillus Calmette Guerin (BCG) (coding for TLR9L); (4) Complete Freund's adjuvant (CFA) (coding for TLR9L); and (5) Incomplete Freund's Adjuvant (IFA). Treatment with poly(I:C), Poly-ICLC, BCG, CFA, or IFA induced anti-tumor activities as measured by 79.1%, 75.94%, 73.94%, 71.88% and 47.75% decreases, respectively in the total number of tumor cells collected 7 days after tumor challenge. Among the tested TLRLs, both poly(I:C) (TLR3L) and BCG (contain TLR9L) showed the highest anti-tumor effects as reflected by the decrease in the number of EAc cells. These effects were associated with a 2-fold increase in the numbers of inflammatory cells expressing the myeloid markers CD11b(+)Ly6G(+), CD11b(+)Ly6G(-), and CD11b(+)Ly6G(-). We concluded that Provision of the proper inflammatory signal with optimally defined magnitude and duration during tumor growth can induce inflammatory immune cells with potent anti-tumor responses without vaccination. PMID:26966565

  4. Acute inflammation induces immunomodulatory effects on myeloid cells associated with anti-tumor responses in a tumor mouse model

    PubMed Central

    Salem, Mohamed L.; Attia, Zeinab I.; Galal, Sohaila M.

    2015-01-01

    Given the self nature of cancer, anti-tumor immune response is weak. As such, acute inflammation induced by microbial products can induce signals that result in initiation of an inflammatory cascade that helps activation of immune cells. We aimed to compare the nature and magnitude of acute inflammation induced by toll-like receptor ligands (TLRLs) on the tumor growth and the associated inflammatory immune responses. To induce acute inflammation in tumor-bearing host, CD1 mice were inoculated with intraperitoneal (i.p.) injection of Ehrlich ascites carcinoma (EAC) (5 × 105 cells/mouse), and then treated with i.p. injection on day 1, day 7 or days 1 + 7 with: (1) polyinosinic:polycytidylic (poly(I:C)) (TLR3L); (2) Poly-ICLC (clinical grade of TLR3L); (3) Bacillus Calmette Guerin (BCG) (coding for TLR9L); (4) Complete Freund’s adjuvant (CFA) (coding for TLR9L); and (5) Incomplete Freund’s Adjuvant (IFA). Treatment with poly(I:C), Poly-ICLC, BCG, CFA, or IFA induced anti-tumor activities as measured by 79.1%, 75.94%, 73.94%, 71.88% and 47.75% decreases, respectively in the total number of tumor cells collected 7 days after tumor challenge. Among the tested TLRLs, both poly(I:C) (TLR3L) and BCG (contain TLR9L) showed the highest anti-tumor effects as reflected by the decrease in the number of EAc cells. These effects were associated with a 2-fold increase in the numbers of inflammatory cells expressing the myeloid markers CD11b+Ly6G+, CD11b+Ly6G−, and CD11b+Ly6G−. We concluded that Provision of the proper inflammatory signal with optimally defined magnitude and duration during tumor growth can induce inflammatory immune cells with potent anti-tumor responses without vaccination. PMID:26966565

  5. Zebrafish as a Model for the Study of Human Myeloid Malignancies.

    PubMed

    Lu, Jeng-Wei; Hsieh, Meng-Shan; Liao, Heng-An; Yang, Yi-Ju; Ho, Yi-Jung; Lin, Liang-In

    2015-01-01

    Myeloid malignancies are heterogeneous disorders characterized by uncontrolled proliferation or/and blockage of differentiation of myeloid progenitor cells. Although a substantial number of gene alterations have been identified, the mechanism by which these abnormalities interact has yet to be elucidated. Over the past decades, zebrafish have become an important model organism, especially in biomedical research. Several zebrafish models have been developed to recapitulate the characteristics of specific myeloid malignancies that provide novel insight into the pathogenesis of these diseases and allow the evaluation of novel small molecule drugs. This report will focus on illustrative examples of applications of zebrafish models, including transgenesis, zebrafish xenograft models, and cell transplantation approaches, to the study of human myeloid malignancies. PMID:26064935

  6. The oncogene EVI1 enhances transcriptional and biological responses of human myeloid cells to all-trans retinoic acid.

    PubMed

    Steinmetz, Birgit; Hackl, Hubert; Slabáková, Eva; Schwarzinger, Ilse; Smějová, Monika; Spittler, Andreas; Arbesu, Itziar; Shehata, Medhat; Souček, Karel; Wieser, Rotraud

    2014-01-01

    The product of the ecotropic virus integration site 1 (EVI1) gene, whose overexpression is associated with a poor prognosis in myeloid leukemias and some epithelial tumors, regulates gene transcription both through direct DNA binding and through modulation of the activity of other sequence specific transcription factors. Previous results from our laboratory have shown that EVI1 influenced transcription regulation in response to the myeloid differentiation inducing agent, all-trans retinoic acid (ATRA), in a dual manner: it enhanced ATRA induced transcription of the RARβ gene, but repressed the ATRA induction of the EVI1 gene itself. In the present study, we asked whether EVI1 would modulate the ATRA regulation of a larger number of genes, as well as biological responses to this agent, in human myeloid cells. U937 and HL-60 cells ectopically expressing EVI1 through retroviral transduction were subjected to microarray based gene expression analysis, and to assays measuring cellular proliferation, differentiation, and apoptosis. These experiments showed that EVI1 modulated the ATRA response of several dozens of genes, and in fact reinforced it in the vast majority of cases. A particularly strong synergy between EVI1 and ATRA was observed for GDF15, which codes for a member of the TGF-β superfamily of cytokines. In line with the gene expression results, EVI1 enhanced cell cycle arrest, differentiation, and apoptosis in response to ATRA, and knockdown of GDF15 counteracted some of these effects. The potential clinical implications of these findings are discussed. PMID:25486480

  7. The oncogene EVI1 enhances transcriptional and biological responses of human myeloid cells to all-trans retinoic acid

    PubMed Central

    Steinmetz, Birgit; Hackl, Hubert; Slabáková, Eva; Schwarzinger, Ilse; Smějová, Monika; Spittler, Andreas; Arbesu, Itziar; Shehata, Medhat; Souček, Karel; Wieser, Rotraud

    2014-01-01

    The product of the ecotropic virus integration site 1 (EVI1) gene, whose overexpression is associated with a poor prognosis in myeloid leukemias and some epithelial tumors, regulates gene transcription both through direct DNA binding and through modulation of the activity of other sequence specific transcription factors. Previous results from our laboratory have shown that EVI1 influenced transcription regulation in response to the myeloid differentiation inducing agent, all-trans retinoic acid (ATRA), in a dual manner: it enhanced ATRA induced transcription of the RARβ gene, but repressed the ATRA induction of the EVI1 gene itself. In the present study, we asked whether EVI1 would modulate the ATRA regulation of a larger number of genes, as well as biological responses to this agent, in human myeloid cells. U937 and HL-60 cells ectopically expressing EVI1 through retroviral transduction were subjected to microarray based gene expression analysis, and to assays measuring cellular proliferation, differentiation, and apoptosis. These experiments showed that EVI1 modulated the ATRA response of several dozens of genes, and in fact reinforced it in the vast majority of cases. A particularly strong synergy between EVI1 and ATRA was observed for GDF15, which codes for a member of the TGF-β superfamily of cytokines. In line with the gene expression results, EVI1 enhanced cell cycle arrest, differentiation, and apoptosis in response to ATRA, and knockdown of GDF15 counteracted some of these effects. The potential clinical implications of these findings are discussed. PMID:25486480

  8. Delineation of Natural Killer Cell Differentiation from Myeloid Progenitors in Human

    PubMed Central

    Chen, Qingfeng; Ye, Weijian; Jian Tan, Wei; Mei Yong, Kylie Su; Liu, Min; Qi Tan, Shu; Loh, Eva; TE Chang, Kenneth; Chye Tan, Thiam; Preiser, Peter R.; Chen, Jianzhu

    2015-01-01

    Understanding of natural killer (NK) cell development in human is incomplete partly because of limited access to appropriate human tissues. We have developed a cytokine-enhanced humanized mouse model with greatly improved reconstitution and function of human NK cells. Here we report the presence of a cell population in the bone marrow of the cytokine-treated humanized mice that express both NK cell marker CD56 and myeloid markers such as CD36 and CD33. The CD56+CD33+CD36+ cells are also found in human cord blood, fetal and adult bone marrow. Although the CD56+CD33+CD36+ cells do not express the common NK cell functional receptors and exhibit little cytotoxic and cytokine-producing activities, they readily differentiate into mature NK cells by acquiring expression of NK cell receptors and losing expression of the myeloid markers. Further studies show that CD33+CD36+ myeloid NK precursors are derived from granulo-myelomonocytic progenitors. These results delineate the pathway of human NK cell differentiation from myeloid progenitors in the bone marrow and suggest the utility of humanized mice for studying human hematopoiesis. PMID:26456148

  9. Delineation of Natural Killer Cell Differentiation from Myeloid Progenitors in Human.

    PubMed

    Chen, Qingfeng; Ye, Weijian; Jian Tan, Wei; Mei Yong, Kylie Su; Liu, Min; Qi Tan, Shu; Loh, Eva; Te Chang, Kenneth; Chye Tan, Thiam; Preiser, Peter R; Chen, Jianzhu

    2015-01-01

    Understanding of natural killer (NK) cell development in human is incomplete partly because of limited access to appropriate human tissues. We have developed a cytokine-enhanced humanized mouse model with greatly improved reconstitution and function of human NK cells. Here we report the presence of a cell population in the bone marrow of the cytokine-treated humanized mice that express both NK cell marker CD56 and myeloid markers such as CD36 and CD33. The CD56(+)CD33(+)CD36(+) cells are also found in human cord blood, fetal and adult bone marrow. Although the CD56(+)CD33(+)CD36(+) cells do not express the common NK cell functional receptors and exhibit little cytotoxic and cytokine-producing activities, they readily differentiate into mature NK cells by acquiring expression of NK cell receptors and losing expression of the myeloid markers. Further studies show that CD33(+)CD36(+) myeloid NK precursors are derived from granulo-myelomonocytic progenitors. These results delineate the pathway of human NK cell differentiation from myeloid progenitors in the bone marrow and suggest the utility of humanized mice for studying human hematopoiesis. PMID:26456148

  10. Myeloid-Derived Suppressor Cells Express Bruton's Tyrosine Kinase and Can Be Depleted in Tumor-Bearing Hosts by Ibrutinib Treatment.

    PubMed

    Stiff, Andrew; Trikha, Prashant; Wesolowski, Robert; Kendra, Kari; Hsu, Vincent; Uppati, Sarvani; McMichael, Elizabeth; Duggan, Megan; Campbell, Amanda; Keller, Karen; Landi, Ian; Zhong, Yiming; Dubovsky, Jason; Howard, John Harrison; Yu, Lianbo; Harrington, Bonnie; Old, Matthew; Reiff, Sean; Mace, Thomas; Tridandapani, Susheela; Muthusamy, Natarajan; Caligiuri, Michael A; Byrd, John C; Carson, William E

    2016-04-15

    Myeloid-derived suppressor cells (MDSC) are a heterogeneous group of immature myeloid cells that expand in tumor-bearing hosts in response to soluble factors produced by tumor and stromal cells. MDSC expansion has been linked to loss of immune effector cell function and reduced efficacy of immune-based cancer therapies, highlighting the MDSC population as an attractive therapeutic target. Ibrutinib, an irreversible inhibitor of Bruton's tyrosine kinase (BTK) and IL2-inducible T-cell kinase (ITK), is in clinical use for the treatment of B-cell malignancies. Here, we report that BTK is expressed by murine and human MDSCs, and that ibrutinib is able to inhibit BTK phosphorylation in these cells. Treatment of MDSCs with ibrutinib significantly impaired nitric oxide production and cell migration. In addition, ibrutinib inhibited in vitro generation of human MDSCs and reduced mRNA expression of indolamine 2,3-dioxygenase, an immunosuppressive factor. Treatment of mice bearing EMT6 mammary tumors with ibrutinib resulted in reduced frequency of MDSCs in both the spleen and tumor. Ibrutinib treatment also resulted in a significant reduction of MDSCs in wild-type mice bearing B16F10 melanoma tumors, but not in X-linked immunodeficiency mice (XID) harboring a BTK mutation, suggesting that BTK inhibition plays an important role in the observed reduction of MDSCs in vivo Finally, ibrutinib significantly enhanced the efficacy of anti-PD-L1 (CD274) therapy in a murine breast cancer model. Together, these results demonstrate that ibrutinib modulates MDSC function and generation, revealing a potential strategy for enhancing immune-based therapies in solid malignancies. Cancer Res; 76(8); 2125-36. ©2016 AACR. PMID:26880800

  11. CD38-Expressing Myeloid-Derived Suppressor Cells Promote Tumor Growth in a Murine Model of Esophageal Cancer.

    PubMed

    Karakasheva, Tatiana A; Waldron, Todd J; Eruslanov, Evgeniy; Kim, Sang-Bae; Lee, Ju-Seog; O'Brien, Shaun; Hicks, Philip D; Basu, Devraj; Singhal, Sunil; Malavasi, Fabio; Rustgi, Anil K

    2015-10-01

    Myeloid-derived suppressor cells (MDSC) are an immunosuppressive population of immature myeloid cells found in advanced-stage cancer patients and mouse tumor models. Production of inducible nitric oxide synthase (iNOS) and arginase, as well as other suppressive mechanisms, allows MDSCs to suppress T-cell-mediated tumor clearance and foster tumor progression. Using an unbiased global gene expression approach in conditional p120-catenin knockout mice (L2-cre;p120ctn(f/f)), a model of oral-esophageal cancer, we have identified CD38 as playing a vital role in MDSC biology, previously unknown. CD38 belongs to the ADP-ribosyl cyclase family and possesses both ectoenzyme and receptor functions. It has been described to function in lymphoid and early myeloid cell differentiation, cell activation, and neutrophil chemotaxis. We find that CD38 expression in MDSCs is evident in other mouse tumor models of esophageal carcinogenesis, and CD38(high) MDSCs are more immature than MDSCs lacking CD38 expression, suggesting a potential role for CD38 in the maturation halt found in MDSC populations. CD38(high) MDSCs also possess a greater capacity to suppress activated T cells, and promote tumor growth to a greater degree than CD38(low) MDSCs, likely as a result of increased iNOS production. In addition, we have identified novel tumor-derived factors, specifically IL6, IGFBP3, and CXCL16, which induce CD38 expression by MDSCs ex vivo. Finally, we have detected an expansion of CD38(+) MDSCs in peripheral blood of advanced-stage cancer patients and validated targeting CD38 in vivo as a novel approach to cancer therapy. PMID:26294209

  12. Hypoxia-inducible factors in human pulmonary arterial hypertension: a link to the intrinsic myeloid abnormalities.

    PubMed

    Farha, Samar; Asosingh, Kewal; Xu, Weiling; Sharp, Jacqueline; George, Deepa; Comhair, Suzy; Park, Margaret; Tang, W H Wilson; Loyd, James E; Theil, Karl; Tubbs, Raymond; Hsi, Eric; Lichtin, Alan; Erzurum, Serpil C

    2011-03-31

    Pulmonary arterial hypertension (PAH) is a proliferative vasculopathy characterized by high circulating CD34(+)CD133(+) proangiogenic progenitors, and endothelial cells that have pathologic expression of hypoxia-inducible factor 1 α (HIF-1α). Here, CD34(+)CD133(+) progenitor cell numbers are shown to be higher in PAH bone marrow, blood, and pulmonary arteries than in healthy controls. The HIF-inducible myeloid-activating factors erythropoietin, stem cell factor (SCF), and hepatocyte growth factor (HGF) are also present at higher than normal levels in PAH blood, and related to disease severity. Primary endothelial cells harvested from human PAH lungs produce greater HGF and progenitor recruitment factor stromal-derived factor 1 α (SDF-1α) than control lung endothelial cells, and thus may contribute to bone marrow activation. Even though PAH patients had normal numbers of circulating blood elements, hematopoietic alterations in myeloid and erythroid lineages and reticulin fibrosis identified a subclinical myeloproliferative process. Unexpectedly, evaluation of bone marrow progenitors and reticulin in nonaffected family members of patients with familial PAH revealed similar myeloid abnormalities. Altogether, the results show that PAH is linked to myeloid abnormalities, some of which may be related to increased production of HIF-inducible factors by diseased pulmonary vasculature, but findings in nonaffected family suggest myeloid abnormalities may be intrinsic to the disease process. PMID:21258008

  13. Hypoxia-inducible factors in human pulmonary arterial hypertension: a link to the intrinsic myeloid abnormalities

    PubMed Central

    Asosingh, Kewal; Xu, Weiling; Sharp, Jacqueline; George, Deepa; Comhair, Suzy; Park, Margaret; Tang, W. H. Wilson; Loyd, James E.; Theil, Karl; Tubbs, Raymond; Hsi, Eric; Lichtin, Alan

    2011-01-01

    Pulmonary arterial hypertension (PAH) is a proliferative vasculopathy characterized by high circulating CD34+CD133+ proangiogenic progenitors, and endothelial cells that have pathologic expression of hypoxia-inducible factor 1 α (HIF-1α). Here, CD34+CD133+ progenitor cell numbers are shown to be higher in PAH bone marrow, blood, and pulmonary arteries than in healthy controls. The HIF-inducible myeloid-activating factors erythropoietin, stem cell factor (SCF), and hepatocyte growth factor (HGF) are also present at higher than normal levels in PAH blood, and related to disease severity. Primary endothelial cells harvested from human PAH lungs produce greater HGF and progenitor recruitment factor stromal-derived factor 1 α (SDF-1α) than control lung endothelial cells, and thus may contribute to bone marrow activation. Even though PAH patients had normal numbers of circulating blood elements, hematopoietic alterations in myeloid and erythroid lineages and reticulin fibrosis identified a subclinical myeloproliferative process. Unexpectedly, evaluation of bone marrow progenitors and reticulin in nonaffected family members of patients with familial PAH revealed similar myeloid abnormalities. Altogether, the results show that PAH is linked to myeloid abnormalities, some of which may be related to increased production of HIF-inducible factors by diseased pulmonary vasculature, but findings in nonaffected family suggest myeloid abnormalities may be intrinsic to the disease process. PMID:21258008

  14. Amino-Biphosphonate–Mediated MMP-9 Inhibition Breaks the Tumor-Bone Marrow Axis Responsible for Myeloid-Derived Suppressor Cell Expansion and Macrophage Infiltration in Tumor Stroma

    PubMed Central

    Melani, Cecilia; Sangaletti, Sabina; Barazzetta, Francesca M.; Werb, Zena; Colombo, Mario P.

    2009-01-01

    BALB-neuT mice expressing an activated rat c-erbB-2/neu transgene under the mouse mammary tumor virus long terminal repeat show enhanced hematopoiesis with hyperproduction of myeloid-derived suppressor cells (MDSC) because of vascular endothelial growth factor (VEGF) secreted by the tumor. Here, we show that both tumor and stromal cells express matrix metalloproteinase-9 (MMP-9), thereby increasing the levels of pro–MMP-9 in the sera of tumor-bearing mice. Treatment with amino-biphosphonates impaired tumor growth, significantly decreased MMP-9 expression and the number of macrophages in tumor stroma, and reduced MDSC expansion both in bone marrow and peripheral blood by dropping serum pro–MMP-9 and VEGF. We dissected the role of tumor-derived MMP-9 from that secreted by stromal leukocytes by transplanting bone marrow from MMP-9 knockout mice into BALB-neuT mice. Although bone marrow progenitor–derived MMP-9 had a major role in driving MDSC expansion, amino-biphosphonate treatment of bone marrow chimeras further reduced both myelopoiesis and the supportive tumor stroma, thus enhancing tumor necrosis. Moreover, by reducing MDSC, amino-biphosphonates overcome the tumor-induced immune suppression and improved the generation and maintenance of antitumor immune response induced by immunization against the p185/HER-2. Our data reveal that suppression of MMP-9 activity breaks the vicious loop linking tumor growth and myeloid cell expansion, thus reducing immunosuppression. Amino-biphosphonates disclose a specific MMP-9 inhibitory activity that may broaden their application above their current usage. PMID:18056472

  15. Regulation of surface expression of the granulocyte/macrophage colony-stimulating factor receptor in normal human myeloid cells

    SciTech Connect

    Cannistra, S.A.; Groshek, P.; Griffin, J.D. ); Garlick, R.; Miller, J. )

    1990-01-01

    Recombinant human granulocyte/macrophage colony-stimulating factor (GM-CSF) exerts stimulatory effects on hematopoietic cells through binding to specific, high-affinity receptors. By using radiolabeled GM-CSF with high specific activity, the authors have investigated the factors and mechanisms that regulate GM-CSF receptor expression in normal human neutrophils, monocytes, and partially purified bone marrow myeloid progenitor cells. The neutrophil GM-CSF receptor was found to rapidly internalize in the presence of ligand through a mechanism that required endocytosis. Out of a large panel of naturally occurring humoral factors tested, only GM-CSF itself, tumor necrosis factor, and formyl-Met-Leu-Phe were found to down-regulate neutrophil GM-CSF receptor expression after a 2-hr exposure at biologically active concentrations. Since formyl-Met-Leu-Phe is known to stimulate neutrophil protein kinase C activity, they also tested the ability of protein kinase C agonists to modulate GM-CSF receptor expression. Phorbol 12-myristate 13-acetate, bryostatin-1, and 1,2-dioctanoylglycerol were found to induce rapid down-regulation of the GM-CSF receptor in neutrophils, monocytes, and partially purified myeloid progenitor cells, suggesting that this effect may be at least partially mediated by protein kinase C. These data suggest that certain activators of neutrophil function may negatively regulate their biological effects by inducing down-regulation of the GM-CSF receptor.

  16. Technical Advance: Transcription factor, promoter, and enhancer utilization in human myeloid cells

    PubMed Central

    Joshi, Anagha; Pooley, Christopher; Freeman, Tom C.; Lennartsson, Andreas; Babina, Magda; Schmidl, Christian; Geijtenbeek, Teunis; Michoel, Tom; Severin, Jessica; Itoh, Masayoshi; Lassmann, Timo; Kawaji, Hideya; Hayashizaki, Yoshihide; Carninci, Piero; Forrest, Alistair R. R.; Rehli, Michael; Hume, David A.

    2015-01-01

    The generation of myeloid cells from their progenitors is regulated at the level of transcription by combinatorial control of key transcription factors influencing cell-fate choice. To unravel the global dynamics of this process at the transcript level, we generated transcription profiles for 91 human cell types of myeloid origin by use of CAGE profiling. The CAGE sequencing of these samples has allowed us to investigate diverse aspects of transcription control during myelopoiesis, such as identification of novel transcription factors, miRNAs, and noncoding RNAs specific to the myeloid lineage. We further reconstructed a transcription regulatory network by clustering coexpressed transcripts and associating them with enriched cis-regulatory motifs. With the use of the bidirectional expression as a proxy for enhancers, we predicted over 2000 novel enhancers, including an enhancer 38 kb downstream of IRF8 and an intronic enhancer in the KIT gene locus. Finally, we highlighted relevance of these data to dissect transcription dynamics during progressive maturation of granulocyte precursors. A multifaceted analysis of the myeloid transcriptome is made available (www.myeloidome.roslin.ed.ac.uk). This high-quality dataset provides a powerful resource to study transcriptional regulation during myelopoiesis and to infer the likely functions of unannotated genes in human innate immunity. PMID:25717144

  17. Tumoral NKG2D alters cell cycle of acute myeloid leukemic cells and reduces NK cell-mediated immune surveillance.

    PubMed

    Tang, Mingying; Acheampong, Desmond Omane; Wang, Youfu; Xie, Wei; Wang, Min; Zhang, Juan

    2016-06-01

    The stimulatory natural killer group 2 member D (NKG2D) lymphocyte receptor, initially discovered and expressed mostly on natural killer (NK) cells, T cells and natural killer T cells, can promote tumor immune surveillance. However, with increasing tumor grade, tumors themselves express NKG2D to self-stimulate oncogenic pathways. To confirm that cancer cells themselves express NKG2D, we have now investigated the role of the tumoral NKG2D in NK cell-mediated immune surveillance. Both anti-NKG2D and shRNA to that down-regulated tumoral NKG2D increased the number of cells in G1 phase and S phase, increased the expression of cyclin E-CDK2 and decreased P21. In addition, CD107a, IFN-γ and TNF-α increased when the cells were treated with anti-NKG2D which suggests that blocking tumoral NKG2D could augment tumor surveillance of NK cells. Altogether, tumoral NKG2D stimulates cell propagation and immune escape in acute myeloid leukemia cells. PMID:26740330

  18. Human Head and Neck Squamous Cell Carcinoma–Associated Semaphorin 4D Induces Expansion of Myeloid-Derived Suppressor Cells

    PubMed Central

    Han, Kyu Lee; Webb, Tonya J.

    2016-01-01

    One of the mechanisms by which malignancies can induce immune suppression is through the production of cytokines that affect the maturation and differentiation of inflammatory cells in the tumor microenvironment. Semaphorin 4D (Sema4D) is a proangiogenic cytokine produced by several malignancies, which has been described in the regulation of the immune system. In the present study, we examined the role of human head and neck squamous cell carcinoma (HNSCC)–secreted Sema4D on myeloid cell differentiation. CD33+ cells cultured in HNSCC cell line–derived conditioned medium differentiated into myeloid derived suppressor cells (MDSC) (CD33+CD11b+HLA-DR−/low). The addition of anti-Sema4D Ab to HNSCC conditioned medium significantly reduced the expansion of the MDSC population. Similarly, knockdown of Sema4D in an HNSCC cell line resulted in a loss of MDSC function as shown by a decrease in the production of the immune-suppressive cytokines arginase-1, TGF-β, and IL-10 by MDSC, concomitant with recovery of T cell proliferation and IFN-γ production following stimulation of CD3/CD28. Importantly, CD33+ myeloid and T cells cultured in conditioned medium of HNSCC cells in which Sema4D was knocked down promoted antitumor inflammatory profile, through recovery of the effector T cells (CD4+T-bet+ and CD8+T-bet+), as well as a decrease in regulatory T cells (CD4+CD25+FOXP3+). We also showed that Sema4D was comparable to GM-CSF in its induction of MDSC. Collectively, this study describes a novel immunosuppressive role for Sema4D in HNSCC through induction of MDSC, and it highlights Sema4D as a therapeutic target for future studies to enhance the antitumorigenic inflammatory response in HNSCC and other epithelial malignancies. PMID:26740106

  19. Phenethyl isothiocyanate inhibits growth of human chronic myeloid leukemia K562 cells via reactive oxygen species generation and caspases.

    PubMed

    Wang, Yating; Wei, Sixi; Wang, Jishi; Fang, Qin; Chai, Qixiang

    2014-07-01

    Phenethyl isothiocyanate (PEITC), a potential cancer chemopreventive constituent of cruciferous vegetables, including watercress, has been reported to inhibit cancer cell growth by arresting the cell cycle and inducing apoptosis in various human cancer cell models. However, the role of PEITC in the inhibition of human chronic myeloid leukemia (CML) K562 cell growth and its underlying mechanisms have yet to be elucidated. In the present study, PEITC was found to induce cell death through the induction of reactive oxygen species (ROS) stress and oxidative damage. Heme oxygenase‑1 (HO‑1), which participates in the development of numerous tumors and the sensitivity of these tumors to chemotherapeutic drugs, plays a protective role by modulating oxidative injury. Therefore, the present study assessed the inhibitory effect of PEITC on K562 cells and whether HO‑1 facilitated cell apoptosis and ROS generation. PEITC was found to suppress cell growth and cause apoptosis by promoting Fas and Fas ligand expression, increasing ROS generation and by the successive release of cytochrome c as well as the activation of caspase‑9 and caspase‑3. PEITC was also combined with the HO‑1 inhibitor zinc protoporphyrin IX and the inducer hemin to assess whether HO‑1 determines cell survival and ROS generation. The results of the present study suggest that PEITC may be a potential anti‑tumor compound for CML therapy, and that HO‑1 has a critical function in PEITC‑induced apoptosis and ROS generation. PMID:24788892

  20. Serum Angiopoietin Levels are Different in Acute and Chronic Myeloid Neoplasms: Angiopoietins do not only Regulate Tumor Angiogenesis.

    PubMed

    Atesoglu, Elif Birtas; Tarkun, Pinar; Mehtap, Ozgur; Demirsoy, Esra Terzi; Atalay, Figen; Maden, Muhammet; Celebi, Koray; Hacihanefioglu, Abdullah

    2016-06-01

    Molecular balance between Angiopoietin-1 (Ang-1) and Angiopoietin-2 (Ang-2) has important effects in tumor angiogenesis. Ang-2 was shown to be elevated and proved to be a prognostic factor in acute myeloid leukemia (AML). To date studies revealed increased angiogenesis in bone marrows (BMs) of both myeloproliferative neoplasm (MPN) and AML patients. We conducted this study to demonstrate circulating levels of Ang-1 and Ang-2 in MPN patients since no data exists in literature. Thirty-three newly diagnosed MPN, 27 newly diagnosed AML patients and 25 controls (HC) were enrolled and Angiopoietin levels were determined with ELISA. We found that Ang-1 levels were higher whereas Ang-2 levels were lower in MPN and HC when compared to AML. Our results suggest that though angiogenesis is increased in both AML and MPN, angiopoietin serum level profile of the two diseases are different, and MPN patients have similar Ang-1 and Ang-2 levels as HC. We conclude that, according to our results Ang-1 and Ang-2 do not only regulate tumor angiogenesis and the difference between angiopoietin levels of acute and chronic myeloid neoplasms could be a reflection of other effects of these growth factors on tumor malignancy. PMID:27065577

  1. The Transcription Factor Wilms Tumor 1 Confers Resistance in Myeloid Leukemia Cells against the Proapoptotic Therapeutic Agent TRAIL (Tumor Necrosis Factor α-related Apoptosis-inducing Ligand) by Regulating the Antiapoptotic Protein Bcl-xL*

    PubMed Central

    Bansal, Hima; Seifert, Theresea; Bachier, Carlos; Rao, Manjeet; Tomlinson, Gail; Iyer, Swaminathan Padmanabhan; Bansal, Sanjay

    2012-01-01

    Tumor necrosis factor α-related apoptosis-inducing ligand (TRAIL) is considered a promising cancer therapeutic agent due to its ability to induce apoptosis in a variety of cancer cells, while sparing normal cells. However, many human tumors including acute myeloid leukemia (AML) are partially or completely resistant to monotherapy with TRAIL, limiting its therapeutic utility. Therefore, identification of factors that contribute to TRAIL resistance may facilitate future development of more effective TRAIL-based cancer therapies. Here, we report a previously unknown role for WT1 in mediating TRAIL resistance in leukemia. Knockdown of WT1 with shRNA rendered TRAIL-resistant myeloid leukemia cells sensitive to TRAIL-induced cell death, and re-expression of shRNA-resistant WT1 restored TRAIL resistance. Notably, TRAIL-mediated apoptosis in WT1-silenced cells was largely due to down-regulation of the antiapoptotic protein Bcl-xL. Moreover, WT1 expression strongly correlated with overexpression of Bcl-xL in AML cell lines and blasts from AML patients. Furthermore, we found that WT1 transactivates Bcl-xL by directly binding to its promoter. We previously showed that WT1 is a novel client protein of heat shock protein 90 (Hsp90). Consistent with this, pharmacological inhibition of Hsp90 resulted in reduced WT1 and Bcl-xL expression leading to increased sensitivity of leukemia cells to TRAIL-mediated apoptosis. Collectively, our results suggest that WT1-dependent Bcl-xL overexpression contributes to TRAIL resistance in myeloid leukemias. PMID:22898820

  2. The stress-response sensor Chop regulates the function and accumulation of myeloid-derived suppressor cells in tumors

    PubMed Central

    Thevenot, Paul T.; Sierra, Rosa A.; Raber, Patrick L.; Al-Khami, Amir A.; Trillo-Tinoco, Jimena; Zarreii, Parisa; Ochoa, Augusto C.; Cui, Yan; Del Valle, Luis; Rodriguez, Paulo C.

    2014-01-01

    Summary Adaptation of malignant cells to the hostile milieu present in tumors is an important determinant for their survival and growth. However, the interaction between tumor-linked stress and anti-tumor immunity remains poorly characterized. Here, we show the critical role of the cellular stress sensor C/EBP-homologous protein (Chop) in the accumulation and immune inhibitory activity of tumor-infiltrating myeloid-derived suppressor cells (MDSCs). MDSCs lacking Chop had decreased immune regulatory functions and showed the ability to prime T cell function and induce anti-tumor responses. Chop expression in MDSCs was induced by tumor-linked reactive oxygen and nitrogen species and regulated by the activating-transcription factor-4. Chop-deficient MDSCs displayed reduced signaling through CCAAT/enhancer-binding protein-β, leading to a decreased production of interleukin-6 (IL-6) and low expression phospho-STAT3. IL-6 over-expression restored immune suppressive activity of Chop-deficient MDSCs. These findings suggest the role of Chop in tumor-induced tolerance and the therapeutic potential of targeting Chop in MDSCs for cancer immunotherapy. PMID:25238096

  3. Host miR-155 promotes tumor growth through a myeloid-derived suppressor cell-dependent mechanism

    PubMed Central

    Chen, Siqi; Wang, Long; Fan, Jie; Ye, Cong; Dominguez, Donye; Zhang, Yi; Curiel, Tyler J.; Fang, Deyu; Kuzel, Timothy M.; Zhang, Bin

    2014-01-01

    miR-155 is a regulator of immune cell development and function that is generally thought to be immunostimulatory. However, we report here that genetic ablation of miR-155 renders mice resistant to chemical carcinogenesis and the growth of several transplanted tumors, suggesting that miR-155 functions in immunosuppression and tumor promotion. Host miR-155 deficiency promoted overall antitumor immunity despite the finding of defective responses of miR-155-deficient dendritic cells and antitumor T cells. Further analysis of immune cell compartments revealed that miR-155 regulated the accumulation of functional myeloid-derived suppressive cells (MDSC) in the tumor microenvironment. Specifically, miR-155 mediated MDSC suppressor activity through at least two mechanisms, including SOCS1 repression and a reduced ability to license the generation of CD4+Foxp3+ regulatory T cells (Treg). Importantly, we demonstrated that miR-155 expression was required for MDSC to facilitate tumor growth. Thus, our results revealed a contextual function for miR-155 in antitumor immunity, with a role in MDSC support that appears to dominate in tumor-bearing hosts. Overall, the balance of these cellular effects appears to be a root determinant of whether miR-155 promotes or inhibits tumor growth. PMID:25502838

  4. Synchronous occurrence of gastrointestinal stromal tumor and acute myeloid leukemia: A case report and review of the literature

    PubMed Central

    GAO, NA; GUO, NONG-JIAN; YU, WEN-ZHENG; WANG, XUE-XIA; SUN, JIAN-RONG; YU, NING; LIU, REN-TONG; LIU, XIAO-DAN; LIU, ZENG-YAN; FENG, RUI

    2016-01-01

    Gastrointestinal stromal tumors (GISTs) originate from the mesenchymal tissue of the gastrointestinal tract. The pathogenesis of GIST is associated with the mutational activation of the receptor tyrosine kinase cluster of differentiation (CD)117 or platelet-derived growth factor receptor-α. Overall, ~60% of GISTs occur in the stomach. Clinically, GISTs may coexist with various types of cancer, including liver cancer, pancreatic tumors and lymphoma, either synchronously or metachronously. The present study reports the case of a patient with the synchronous occurrence of a CD117-positive GIST and acute myeloid leukemia. A 69-year-old man was hospitalized for heart palpitations and dizziness, and was diagnosed with acute myeloid leukemia (AML) by bone marrow aspiration and flow cytometry analysis. An abdominal computed tomograpy and gastroscopy revealed the presence of GIST. The patient received chemotherapy in combination with imatinib (400 mg/day), and the mass was removed 2 months later. To the best of our knowledge, the present study is the first reported case of the synchronous development of a CD117-positive GIST and AML. Additional studies are required in order to understand the association between GIST and hematological malignancies. PMID:27123049

  5. Inhibition of A20 expression in tumor microenvironment exerts anti-tumor effect through inducing myeloid-derived suppressor cells apoptosis

    PubMed Central

    Shao, Bin; Wei, Xiawei; Luo, Min; Yu, Jiayun; Tong, Aiping; Ma, Xuelei; Ye, Tinghong; Deng, Hongxin; Sang, Yaxiong; Liang, Xiao; Ma, Yu; Wu, Qinjie; Du, Wei; Du, Jing; Gao, Xiang; Wen, Yi; Fu, Ping; Shi, Huashan; Luo, Shuntao; Wei, Yuquan

    2015-01-01

    Myeloid-derived suppressor cells (MDSCs) are known to play important roles in the development of immunosuppressive tumor microenvironment. A20 is a zinc-finger protein which could negatively regulate apoptosis in several cell types. However, the role of A20 in tumor microenvironment remains largely unknown. In this study, we found that A20 was over-expressed in MDSCs. The treatment of tumor-bearing mice with small interfering RNA targeting A20 (si-A20) inhibited the growth of tumors. The infiltration of MDSCs was dramatically reduced after si-A20 treatment, as compared to control groups, whereas the numbers of dendritic cells and macrophages were not affected. Also, injection of si-A20 improved T cell mediated tumor-specific immune response. Depletion of MDSCs with anti-Gr1 antibody showed similar antitumor effect and improved T cell response. TNF-α was highly expressed after si-A20 injection. Furthermore, si-A20 induced apoptosis of MDSCs in the presence of TNF-α both in vivo and in vitro. Cleaved Caspase-3 and Caspase-8 were elevated with the activation of JNK pathway after the induction of MDSC apoptosis by si-A20. Thus, our findings suggested that knockdown of A20 in tumor site inhibited tumor growth at least through inducing the apoptosis of MDSCs. A20 might be a potential target in anticancer therapy. PMID:26561336

  6. A Hyperactive Signalosome in Acute Myeloid Leukemia Drives Addiction to a Tumor-Specific Hsp90 Species.

    PubMed

    Zong, Hongliang; Gozman, Alexander; Caldas-Lopes, Eloisi; Taldone, Tony; Sturgill, Eric; Brennan, Sarah; Ochiana, Stefan O; Gomes-DaGama, Erica M; Sen, Siddhartha; Rodina, Anna; Koren, John; Becker, Michael W; Rudin, Charles M; Melnick, Ari; Levine, Ross L; Roboz, Gail J; Nimer, Stephen D; Chiosis, Gabriela; Guzman, Monica L

    2015-12-15

    Acute myeloid leukemia (AML) is a heterogeneous and fatal disease with an urgent need for improved therapeutic regimens given that most patients die from relapsed disease. Irrespective of mutation status, the development of aggressive leukemias is enabled by increasing dependence on signaling networks. We demonstrate that a hyperactive signalosome drives addiction of AML cells to a tumor-specific Hsp90 species (teHsp90). Through genetic, environmental, and pharmacologic perturbations, we demonstrate a direct and quantitative link between hyperactivated signaling pathways and apoptotic sensitivity of AML to teHsp90 inhibition. Specifically, we find that hyperactive JAK-STAT and PI3K-AKT signaling networks are maintained by teHsp90 and, in fact, gradual activation of these networks drives tumors increasingly dependent on teHsp90. Thus, although clinically aggressive AML survives via signalosome activation, this addiction creates a vulnerability that can be exploited with Hsp90-directed therapy. PMID:26628369

  7. Correlation between myeloid-derived suppressor cells and S100A8/A9 in tumor and autoimmune diseases.

    PubMed

    Zheng, Ruoting; Chen, Shiyi; Chen, Shenren

    2015-12-01

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of cells that constitute an important component of immune regulatory system. Two calcium-binding proteins S100A8 and S100A9 act as important mediators in acute and chronic inflammation. In recent years, many researchers have found that MDSCs and S100A8/A9 operated with one another through a positive feedback loop to promote tumor development and metastasis. However, the correlation between MDSCs and S100A8/A9 in autoimmune diseases (AIDs) remains unknown. In this review, we discussed the co-operation of MDSCs and S100A8/A9 in tumor environment, and also, the role of these two components in AIDs. PMID:26508452

  8. Sunitinib depletes myeloid-derived suppressor cells and synergizes with a cancer vaccine to enhance antigen-specific immune responses and tumor eradication

    PubMed Central

    Draghiciu, Oana; Nijman, Hans W; Hoogeboom, Baukje Nynke; Meijerhof, Tjarko; Daemen, Toos

    2015-01-01

    The high efficacy of therapeutic cancer vaccines in preclinical studies has yet to be fully achieved in clinical trials. Tumor immune suppression is a critical factor that hampers the desired antitumor effect. Here, we analyzed the combined effect of a cancer vaccine and the receptor tyrosine kinase inhibitor sunitinib. Sunitinib was administered intraperitoneally, alone or in combination with intramuscular immunization using a viral vector based cancer vaccine composed of Semliki Forest virus replicon particles and encoding the oncoproteins E6 and E7 (SFVeE6,7) of human papilloma virus (HPV). We first demonstrated that treatment of tumor-bearing mice with sunitinib alone dose-dependently depleted myeloid-derived suppressor cells (MDSCs) in the tumor, spleen and in circulation. Concomitantly, the number of CD8+ T cells increased 2–fold and, on the basis of CD69 expression, their activation status was greatly enhanced. The intrinsic immunosuppressive activity of residual MDSCs after sunitinib treatment was not changed in a dose-dependent fashion. We next combined sunitinib treatment with SFVeE6,7 immunization. This combined treatment resulted in a 1.5- and 3-fold increase of E7-specific cytotoxic T lymphocytes (CTLs) present within the circulation and tumor, respectively, as compared to immunization only. The ratio of E7-specific CTLs to MDSCs in blood thereby increased 10- to 20-fold and in tumors up to 12.5-fold. As a result, the combined treatment strongly enhanced the antitumor effect of the cancer vaccine. This study demonstrates that sunitinib creates a favorable microenvironment depleted of MDSCs and acts synergistically with a cancer vaccine resulting in enhanced levels of active tumor-antigen specific CTLs, thus changing the balance in favor of antitumor immunity. PMID:25949902

  9. Crucial involvement of xanthine oxidase in the intracellular signalling networks associated with human myeloid cell function

    PubMed Central

    Abooali, Maryam; Lall, Gurprit S.; Coughlan, Karen; Lall, Harjinder S.; Gibbs, Bernhard F.; Sumbayev, Vadim V.

    2014-01-01

    Xanthine oxidase (XOD) is an enzyme which plays a central role in purine catabolism by converting hypoxanthine into xanthine and then further into uric acid. Here we report that XOD is activated in THP-1 human myeloid cells in response to pro-inflammatory and growth factor stimulation. This effect occurred following stimulation of THP-1 cells with ligands of plasma membrane associated TLRs 2 and 4, endosomal TLRs 7 and 8 as well as stem cell growth factor (SCF). Hypoxia-inducible factor 1 (HIF-1) and activator protein 1 (AP-1) transcription complexes were found to be responsible for XOD upregulation. Importantly, the mammalian target of rapamycin (mTOR), a major myeloid cell translation regulator, was also found to be essential for XOD activation. Specific inhibition of XOD by allopurinol and sodium tungstate led to an increase in intracellular AMP levels triggering downregulation of mTOR activation by phosphorylation of its T2446 residue. Taken together, our results demonstrate for the first time that XOD is not only activated by pro-inflammatory stimuli or SCF but also plays an important role in maintaining mTOR-dependent translational control during the biological responses of human myeloid cells. PMID:25200751

  10. Crucial involvement of xanthine oxidase in the intracellular signalling networks associated with human myeloid cell function.

    PubMed

    Abooali, Maryam; Lall, Gurprit S; Coughlan, Karen; Lall, Harjinder S; Gibbs, Bernhard F; Sumbayev, Vadim V

    2014-01-01

    Xanthine oxidase (XOD) is an enzyme which plays a central role in purine catabolism by converting hypoxanthine into xanthine and then further into uric acid. Here we report that XOD is activated in THP-1 human myeloid cells in response to pro-inflammatory and growth factor stimulation. This effect occurred following stimulation of THP-1 cells with ligands of plasma membrane associated TLRs 2 and 4, endosomal TLRs 7 and 8 as well as stem cell growth factor (SCF). Hypoxia-inducible factor 1 (HIF-1) and activator protein 1 (AP-1) transcription complexes were found to be responsible for XOD upregulation. Importantly, the mammalian target of rapamycin (mTOR), a major myeloid cell translation regulator, was also found to be essential for XOD activation. Specific inhibition of XOD by allopurinol and sodium tungstate led to an increase in intracellular AMP levels triggering downregulation of mTOR activation by phosphorylation of its T2446 residue. Taken together, our results demonstrate for the first time that XOD is not only activated by pro-inflammatory stimuli or SCF but also plays an important role in maintaining mTOR-dependent translational control during the biological responses of human myeloid cells. PMID:25200751

  11. ERK5 pathway regulates transcription factors important for monocytic differentiation of human myeloid leukemia cells.

    PubMed

    Wang, Xuening; Pesakhov, Stella; Harrison, Jonathan S; Danilenko, Michael; Studzinski, George P

    2014-07-01

    Mitogen-activated protein kinases (MAPKs) are important transducers of external signals for cell growth, survival, and other cellular responses including cell differentiation. Several MAPK cascades are known with the MEK1/2-ERK1/2, JNK, and p38MAPKs receiving most attention, but the role of MEK5-ERK5 in intracellular signaling deserves more scrutiny, as this pathway transmits signals that can complement ERK/2 signaling. We hypothesized that the ERK5 pathway plays a role in the control of monocytic differentiation, which is disturbed in myeloid leukemia. We therefore examined the cellular phenotype and key molecular events which occur when human myeloid leukemia cells, acute (AML) or chronic (CML), are forced to differentiate by vitamin D derivatives (VDDs). This study was performed using established cell lines HL60 and U937, and primary cultures of blasts from 10 patients with ML. We found that ERK5 and its direct downstream target transcription factor MEF2C are upregulated by 1,25D in parallel with monocytic differentiation. Further, inhibition of ERK5 activity by specific pharmacological agents BIX02189 and XMD8-92 alters the phenotype of these cells by reducing the abundance of the VDD-induced surface monocytic marker CD14, and concomitantly increasing surface expression of the general myeloid marker CD11b. Similar results were obtained when the expression of ERK5 was reduced by siRNA or short hairpin (sh) RNA. ERK5 inhibition resulted in an expected decrease in MEF2C activation. We also found that in AML cells the transcription factor C/EBPβ is positively regulated, while C/EBPα is negatively regulated by ERK5. These findings provide new understanding of dysregulated differentiation in human myeloid leukemia. PMID:24264602

  12. ERK5 Pathway Regulates Transcription Factors Important for Monocytic Differentiation of Human Myeloid Leukemia Cells†

    PubMed Central

    Wang, Xuening; Pesakhov, Stella; Harrison, Jonathan S; Danilenko, Michael; Studzinski, George P

    2014-01-01

    Mitogen-activated protein kinases (MAPKs) are important transducers of external signals for cell growth, survival and other cellular responses including cell differentiation. Several MAPK cascades are known with the MEK1/2-ERK1/2, JNK, and p38MAPKs receiving most attention, but the role of MEK5-ERK5 in intracellular signaling deserves more scrutiny, as this pathway transmits signals that can complement ERK/2 signaling. We hypothesized that the ERK5 pathway plays a role in the control of monocytic differentiation, which is disturbed in myeloid leukemia. We therefore examined the cellular phenotype and key molecular events which occur when human myeloid leukemia cells, acute (AML) or chronic (CML), are forced to differentiate by vitamin D derivatives (VDDs). This study was performed using established cell lines HL60 and U937, and primary cultures of blasts from 10 patients with ML. We found that ERK5 and its direct downstream target transcription factor MEF2C are upregulated by 1,25D in parallel with monocytic differentiation. Further, inhibition of ERK5 activity by specific pharmacological agents BIX02189 and XMD8-92 alters the phenotype of these cells by reducing the abundance of the VDD-induced surface monocytic marker CD14, and concomitantly increasing surface expression of the general myeloid marker CD11b. Similar results were obtained when the expression of ERK5 was reduced by siRNA or short hairpin (sh) RNA. ERK5 inhibition resulted in an expected decrease in MEF2C activation. We also found that in AML the transcription factor C/EBPβ is positively regulated, while C/EBPα is negatively regulated by ERK5. These findings provide new understanding of dysregulated differentiation in human myeloid leukemia. PMID:24264602

  13. IL-12 and type I IFN response of neonatal myeloid DC to human CMV infection.

    PubMed

    Renneson, Joelle; Dutta, Binita; Goriely, Stanislas; Danis, Bénédicte; Lecomte, Sandra; Laes, Jean-François; Tabi, Zsuzsanna; Goldman, Michel; Marchant, Arnaud

    2009-10-01

    Following congenital human CMV (HCMV) infection, 15-20% of infected newborns develop severe health problems whereas infection in immunocompetent adults rarely causes illness. The immaturity of neonatal antigen presenting cells could play a pivotal role in this susceptibility. Neonatal myeloid DC were shown to be deficient in IFN-beta and IL-12 synthesis in response to TLR triggering. We studied the response of cord and adult blood-derived myeloid DC to HCMV infection. Neonatal and adult DC were equally susceptible to in vitro HCMV infection. Among immunomodulatory cytokines, IL-12, IFN-beta and IFN-lambda1 were produced at lower levels by neonatal as compared with adult DC. In contrast, neonatal and adult DC produced similar levels of IFN-alpha and IFN-inducible genes. Microarray analysis indicated that among the more than thousand genes up- or down-regulated by HCMV infection of myeloid DC, 88 were differently regulated between adult and neonatal DC. We conclude that neonatal and adult DC trigger a partly different response to HCMV infection. The deficient IL-12 and mature IFN-alpha production by neonatal DC exposed to HCMV are likely to influence the quality of the T lymphocyte response to HCMV infection in early life. PMID:19637227

  14. Vorinostat and Decitabine in Treating Patients With Advanced Solid Tumors or Relapsed or Refractory Non-Hodgkin's Lymphoma, Acute Myeloid Leukemia, Acute Lymphocytic Leukemia, or Chronic Myelogenous Leukemia

    ClinicalTrials.gov

    2014-08-26

    ; Stage IV Small Lymphocytic Lymphoma; Unspecified Adult Solid Tumor, Protocol Specific; Untreated Adult Acute Lymphoblastic Leukemia; Untreated Adult Acute Myeloid Leukemia

  15. Immunotherapy against Metastatic Melanoma with Human iPS Cell-Derived Myeloid Cell Lines Producing Type I Interferons.

    PubMed

    Miyashita, Azusa; Fukushima, Satoshi; Nakahara, Satoshi; Kubo, Yosuke; Tokuzumi, Aki; Yamashita, Junji; Aoi, Jun; Haruta, Miwa; Senju, Satoru; Nishimura, Yasuharu; Jinnin, Masatoshi; Ihn, Hironobu

    2016-03-01

    In recent years, immunotherapy for advanced melanoma has been gaining increased attention. The efficacy of anti-cytotoxic T-lymphocyte antigen 4 antibodies, anti-programmed cell death 1 antibodies, and the BRAF(V600E) kinase inhibitor has been proven in metastatic melanoma. At the same time, adoptive cell transfer has significant effects against metastatic melanoma; however, it is difficult to apply on a broad scale because of the problems related to cell preparation. To overcome these problems, we developed immune cell therapy using induced pluripotent stem (iPS) cells. The benefit of our method is that a large number of cells can be readily obtained. We focused on macrophages for immune cell therapy because macrophage infiltration is frequently observed in solid cancers. In this study, the efficacy of human iPS cell-derived myeloid cell lines (iPS-ML) genetically modified to express type I IFNs against human melanoma cells was examined. The morphology, phagocytic ability, and surface markers of iPS-ML were similar to those of macrophages. The iPS-ML that express type I IFNs (iPS-ML-IFN) showed significant effects in inhibiting the growth of disseminated human melanoma cells in SCID mice. The infiltration of iPS-ML into the tumor nests was confirmed immunohistologically. The iPS-ML-IFNs increased the expression of CD169, a marker of M1 macrophages that can activate antitumor immunity. The iPS-ML-IFNs could infiltrate into tumor tissue and exert anticancer effects in the local tumor tissue. In conclusion, this method will provide a new therapeutic modality for metastatic melanoma. Cancer Immunol Res; 4(3); 248-58. ©2015 AACR. PMID:26714554

  16. Ex vivo generation of myeloid-derived suppressor cells that model the tumor immunosuppressive environment in colorectal cancer

    PubMed Central

    Dufait, Inès; Schwarze, Julia Katharina; Liechtenstein, Therese; Leonard, Wim; Jiang, Heng; Escors, David

    2015-01-01

    Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of cells that accumulate in tumor-bearing subjects and which strongly inhibit anti-cancer immune responses. To study the biology of MDSC in colorectal cancer (CRC), we cultured bone marrow cells in conditioned medium from CT26 cells, which are genetically modified to secrete high levels of granulocyte-macrophage colony-stimulating factor. This resulted in the generation of high numbers of CD11b+ Ly6G+ granulocytic and CD11b+ Ly6C+ monocytic MDSC, which closely resemble those found within the tumor but not the spleen of CT26 tumor-bearing mice. Such MDSC potently inhibited T-cell responses in vitro, a process that could be reversed upon blocking of arginase-1 or inducible nitric oxide synthase (iNOS). We confirmed that inhibition of arginase-1 or iNOS in vivo resulted in the stimulation of cytotoxic T-cell responses. A delay in tumor growth was observed upon functional repression of both enzymes. These data confirm the role of MDSC as inhibitors of T-cell-mediated immune responses in CRC. Moreover, MDSC differentiated in vitro from bone marrow cells using conditioned medium of GM-CSF-secreting CT26 cells, represent a valuable platform to study/identify drugs that counteract MDSC activities. PMID:25869209

  17. The retinoblastoma gene in human pituitary tumors

    SciTech Connect

    Cryns, V.L.; Arnold, A.; Alexander, J.M.; Klibanski, A. )

    1993-09-01

    Functional inactivation of the retinoblastoma (RB) tumor suppressor gene is important in the pathogenesis of many human tumors. Recently, the frequent occurrence of pituitary tumors was reported in mice genetically engineered to have one defective RB allele, a genetic background analogous to that of patients with familial retinoblastoma. The molecular pathogenesis of human pituitary tumors is largely unknown, and the potential role of RB gene inactivation in these neoplasms has not been examined. Consequently, the authors studied 20 human pituitary tumors (12 clinically nonfunctioning tumors, 4 somatotroph adenomas, 2 prolactinomas, and 2 corticotrophy adenomas) for tumor-specific allelic loss of the RB gene using a highly informative polymorphic locus within the gene. Control leukocyte DNA samples from 18 of these 20 patients were heterozygous at this locus, permitting genetic evaluation of their paired tumor specimens. In contrast to the pituitary tumors in the mouse model, none of these 18 human tumors exhibited RB allelic loss. These findings indicate that RB gene inactivation probably does not play an important role in the pathogenesis of common types of human pituitary tumors. 24 refs., 1 fig.

  18. Cross-talk among myeloid-derived suppressor cells, macrophages, and tumor cells impacts the inflammatory milieu of solid tumors

    PubMed Central

    Beury, Daniel W.; Parker, Katherine H.; Nyandjo, Maeva; Sinha, Pratima; Carter, Kayla A.; Ostrand-Rosenberg, Suzanne

    2014-01-01

    MDSC and macrophages are present in most solid tumors and are important drivers of immune suppression and inflammation. It is established that cross-talk between MDSC and macrophages impacts anti-tumor immunity; however, interactions between tumor cells and MDSC or macrophages are less well studied. To examine potential interactions between these cells, we studied the impact of MDSC, macrophages, and four murine tumor cell lines on each other, both in vitro and in vivo. We focused on IL-6, IL-10, IL-12, TNF-α, and NO, as these molecules are produced by macrophages, MDSC, and many tumor cells; are present in most solid tumors; and regulate inflammation. In vitro studies demonstrated that MDSC-produced IL-10 decreased macrophage IL-6 and TNF-α and increased NO. IL-6 indirectly regulated MDSC IL-10. Tumor cells increased MDSC IL-6 and vice versa. Tumor cells also increased macrophage IL-6 and NO and decreased macrophage TNF-α. Tumor cell-driven macrophage IL-6 was reduced by MDSC, and tumor cells and MDSC enhanced macrophage NO. In vivo analysis of solid tumors identified IL-6 and IL-10 as the dominant cytokines and demonstrated that these molecules were produced predominantly by stromal cells. These results suggest that inflammation within solid tumors is regulated by the ratio of tumor cells to MDSC and macrophages and that interactions of these cells have the potential to alter significantly the inflammatory milieu within the tumor microenvironment. PMID:25170116

  19. Tasquinimod modulates tumor-infiltrating myeloid cells and improves the antitumor immune response to PD-L1 blockade in bladder cancer

    PubMed Central

    Nakhlé, Jessica; Pierron, Valérie; Bauchet, Anne-Laure; Plas, Pascale; Thiongane, Amath; Meyer-Losic, Florence; Schmidlin, Fabien

    2016-01-01

    ABSTRACT The infiltration of myeloid cells helps tumors to overcome immune surveillance and imparts resistance to cancer immunotherapy. Thus, strategies to modulate the effects of these immune cells may offer a potential therapeutic benefit. We report here that tasquinimod, a novel immunotherapy which targets S100A9 signaling, reduces the immunosuppressive properties of myeloid cells in preclinical models of bladder cancer (BCa). As single anticancer agent, tasquinimod treatment was effective in preventing early stage tumor growth, but did not achieve a clear antitumor effect in advanced tumors. Investigations of this response revealed that tasquinimod induces an increase in the expression of a negative regulator of T cell activation, Programmed-death-ligand 1 (PD-L1). This markedly weakens its antitumor immunity, yet provokes an “inflamed” milieu rendering tumors more prone to T cell-mediated immune attack by PD-L1 blockade. Interestingly, the combination of tasquinimod with an Anti-PD-L1 antibody enhanced the antitumor immune response in bladder tumors. This combination synergistically modulated tumor-infiltrating myeloid cells, thereby strongly affecting proliferation and activation of effector T cells. Together, our data provide insight into the rational combination of therapies that activate both innate and adaptive immune system, such as the association of S100A9-targeting agents with immune checkpoints inhibitors, to improve the response to cancer immunotherapeutic agents in BCa. PMID:27471612

  20. Paving the Road to Tumor Development and Spreading: Myeloid-Derived Suppressor Cells are Ruling the Fate

    PubMed Central

    Meirow, Yaron; Kanterman, Julia; Baniyash, Michal

    2015-01-01

    Cancer development is dependent on intrinsic cellular changes as well as inflammatory factors in the tumor macro and microenvironment. The inflammatory milieu nourishes the tumor and contributes to cancer progression. Numerous studies, including ours, have demonstrated that the tumor microenvironment is immunosuppressive, impairing the anticancer immune responses. Chronic inflammation was identified as the key process responsible for this immunosuppression via induction of immature myeloid-derived suppressor cells (MDSCs). Upon a prolonged immune response, MDSCs are polarized toward immunosuppressive cells meant to control the exacerbated immune response. In cancer, the chronic inflammatory response renders the MDSCs harmful. Polarized MDSCs suppress T-cells and natural killer cells, as well as antigen-presenting cells, abrogating the beneficial immune response. These changes in the immunological milieu could also lead to high frequency of mutations, enhanced cancer cell stemness, and angiogenesis, directly supporting tumor initiation, growth, and spreading. The presence of MDSCs in cancer poses a serious obstacle in a variety of immune-based therapies, which rely on the stimulation of antitumor immune responses. Cumulative data, including our own, suggest that the selection of an appropriate and effective anticancer therapy must take into consideration the host’s immune status as well as tumor-related parameters. Merging biomarkers for immune monitoring into the traditional patient’s categorization and follow-up can provide new predictive and diagnostic tools to the clinical practice. Chronic inflammation and MDSCs could serve as novel targets for therapeutic interventions, which can be combined with conventional cancer treatments such as chemotherapy, radiotherapy, and cancer cell-targeted and immune-based therapies. Intervention in environmental and tumor-specific inflammatory mechanisms will allow better clinical management of cancer toward more efficient

  1. Paving the Road to Tumor Development and Spreading: Myeloid-Derived Suppressor Cells are Ruling the Fate.

    PubMed

    Meirow, Yaron; Kanterman, Julia; Baniyash, Michal

    2015-01-01

    Cancer development is dependent on intrinsic cellular changes as well as inflammatory factors in the tumor macro and microenvironment. The inflammatory milieu nourishes the tumor and contributes to cancer progression. Numerous studies, including ours, have demonstrated that the tumor microenvironment is immunosuppressive, impairing the anticancer immune responses. Chronic inflammation was identified as the key process responsible for this immunosuppression via induction of immature myeloid-derived suppressor cells (MDSCs). Upon a prolonged immune response, MDSCs are polarized toward immunosuppressive cells meant to control the exacerbated immune response. In cancer, the chronic inflammatory response renders the MDSCs harmful. Polarized MDSCs suppress T-cells and natural killer cells, as well as antigen-presenting cells, abrogating the beneficial immune response. These changes in the immunological milieu could also lead to high frequency of mutations, enhanced cancer cell stemness, and angiogenesis, directly supporting tumor initiation, growth, and spreading. The presence of MDSCs in cancer poses a serious obstacle in a variety of immune-based therapies, which rely on the stimulation of antitumor immune responses. Cumulative data, including our own, suggest that the selection of an appropriate and effective anticancer therapy must take into consideration the host's immune status as well as tumor-related parameters. Merging biomarkers for immune monitoring into the traditional patient's categorization and follow-up can provide new predictive and diagnostic tools to the clinical practice. Chronic inflammation and MDSCs could serve as novel targets for therapeutic interventions, which can be combined with conventional cancer treatments such as chemotherapy, radiotherapy, and cancer cell-targeted and immune-based therapies. Intervention in environmental and tumor-specific inflammatory mechanisms will allow better clinical management of cancer toward more efficient

  2. Epstein-Barr virus episome-based promoter function in human myeloid cells.

    PubMed Central

    Hauer, C A; Getty, R R; Tykocinski, M L

    1989-01-01

    Epstein-Barr virus (EBV) episomal replicons offer an expeditious means for amplifying transfected genes in human cells. A panel of EBV episomes was constructed to assess the relative utility of five distinct eukaryotic promoter elements for high level and inducible gene expression in stably transfected human myeloid leukemia cells. The Rous sarcoma virus 3' long terminal repeat (LTR) was most highly suited for EBV episome-based gene expression, whereas the lymphopapilloma virus and the SV40 early regulatory elements exhibited substantially lower activities. Chemically responsive promoter elements, such as the SV40 early, human metallothionein IIA and rat GRP78 gene promoters, retained their inducibility when EBV episome-based. Differences in gene expression obtained with the episomes reflected differential promoter activity rather than significant variations in episome copy numbers per cell. These observations provide guidelines for the optimal design of EBV episomal expression vectors for human expression work. Images PMID:2538801

  3. Targeting myeloid-derived suppressor cells with colony stimulating factor-1 receptor blockade can reverse immune resistance to immunotherapy in indoleamine 2,3-dioxygenase-expressing tumors

    PubMed Central

    Holmgaard, Rikke B.; Zamarin, Dmitriy; Lesokhin, Alexander; Merghoub, Taha; Wolchok, Jedd D.

    2016-01-01

    Tumor indoleamine 2,3-dioxygenase (IDO) promotes immunosuppression by direct action on effector T cells and Tregs and through recruitment, expansion and activation of myeloid-derived suppressor cells (MDSCs). Targeting of MDSCs is clinically being explored as a therapeutic strategy, though optimal targeting strategies and biomarkers predictive of response are presently unknown. Maturation and tumor recruitment of MDSCs are dependent on signaling through the receptor tyrosine kinase CSF-1R on myeloid cells. Here, we show that MDSCs are the critical cell population in IDO-expressing B16 tumors in mediating accelerated tumor outgrowth and resistance to immunotherapy. Using a clinically relevant drug, we show that inhibition of CSF-1R signaling can functionally block tumor-infiltrating MDSCs and enhance anti-tumor T cell responses. Furthermore, inhibition of CSF-1R sensitizes IDO-expressing tumors to immunotherapy with T cell checkpoint blockade, and combination of CSF-1R blockade with IDO inhibitors potently elicits tumor regression. These findings provide evidence for a critical and functional role for MDSCs on the in vivo outcome of IDO-expressing tumors. PMID:27211548

  4. A proteomic chronology of gene expression through the cell cycle in human myeloid leukemia cells

    PubMed Central

    Ly, Tony; Ahmad, Yasmeen; Shlien, Adam; Soroka, Dominique; Mills, Allie; Emanuele, Michael J; Stratton, Michael R; Lamond, Angus I

    2014-01-01

    Technological advances have enabled the analysis of cellular protein and RNA levels with unprecedented depth and sensitivity, allowing for an unbiased re-evaluation of gene regulation during fundamental biological processes. Here, we have chronicled the dynamics of protein and mRNA expression levels across a minimally perturbed cell cycle in human myeloid leukemia cells using centrifugal elutriation combined with mass spectrometry-based proteomics and RNA-Seq, avoiding artificial synchronization procedures. We identify myeloid-specific gene expression and variations in protein abundance, isoform expression and phosphorylation at different cell cycle stages. We dissect the relationship between protein and mRNA levels for both bulk gene expression and for over ∼6000 genes individually across the cell cycle, revealing complex, gene-specific patterns. This data set, one of the deepest surveys to date of gene expression in human cells, is presented in an online, searchable database, the Encyclopedia of Proteome Dynamics (http://www.peptracker.com/epd/). DOI: http://dx.doi.org/10.7554/eLife.01630.001 PMID:24596151

  5. Pegylated Gold Nanoparticles Induce Apoptosis in Human Chronic Myeloid Leukemia Cells

    PubMed Central

    Huang, Yu-Chuen; Yang, Yuh-Cheng; Yang, Kai-Chien; Shieh, Hui-Ru; Wang, Tao-Yeuan; Hwu, Yeukuang

    2014-01-01

    Gold nanoparticles (AuNPs) have several potential biological applications as well as excellent biocompatibility. AuNPs with surface modification using polyethylene glycol (PEG-AuNPs) can facilitate easy conjugation with various biological molecules of interest. To examine the anticancer bioactivity of PEG-AuNPs, we investigated their effect on human chronic myeloid leukemia K562 cells. The results indicated that PEG-AuNPs markedly inhibited the viability and impaired the cell membrane integrity of K562 cells. The particles caused morphological changes typical of cell death, and a marked increase in the sub-G1 population in DNA histogram, indicating apoptosis. In addition, PEG-AuNPs reduced the mitochondrial transmembrane potential, a hallmark of the involvement of intrinsic apoptotic pathway in K562 cells. Observation of ultrastructure under a transmission electron microscope revealed that the internalized PEG-AuNPs were distributed into cytoplasmic vacuoles and damaged mitochondria, and subsequently accumulated in areas surrounding the nuclear membrane. In conclusion, PEG-AuNPs may have the potential to inhibit growth and induce apoptosis in human chronic myeloid leukemia cells. PMID:24790990

  6. MerTK Is a Functional Regulator of Myelin Phagocytosis by Human Myeloid Cells.

    PubMed

    Healy, Luke M; Perron, Gabrielle; Won, So-Yoon; Michell-Robinson, Mackenzie A; Rezk, Ayman; Ludwin, Samuel K; Moore, Craig S; Hall, Jeffery A; Bar-Or, Amit; Antel, Jack P

    2016-04-15

    Multifocal inflammatory lesions featuring destruction of lipid-rich myelin are pathologic hallmarks of multiple sclerosis. Lesion activity is assessed by the extent and composition of myelin uptake by myeloid cells present in such lesions. In the inflamed CNS, myeloid cells are comprised of brain-resident microglia, an endogenous cell population, and monocyte-derived macrophages, which infiltrate from the systemic compartment. Using microglia isolated from the adult human brain, we demonstrate that myelin phagocytosis is dependent on the polarization state of the cells. Myelin ingestion is significantly enhanced in cells exposed to TGF-β compared with resting basal conditions and markedly reduced in classically activated polarized cells. Transcriptional analysis indicated that TGF-β-treated microglia closely resembled M0 cells. The tyrosine kinase phagocytic receptor MerTK was one of the most upregulated among a select number of differentially expressed genes in TGF-β-treated microglia. In contrast, MerTK and its known ligands, growth arrest-specific 6 and Protein S, were downregulated in classically activated cells. MerTK expression and myelin phagocytosis were higher in CNS-derived microglia than observed in monocyte-derived macrophages, both basally and under all tested polarization conditions. Specific MerTK inhibitors reduced myelin phagocytosis and the resultant anti-inflammatory biased cytokine responses for both cell types. Defining and modulating the mechanisms that regulate myelin phagocytosis has the potential to impact lesion and disease evolution in multiple sclerosis. Relevant effects would include enhancing myelin clearance, increasing anti-inflammatory molecule production by myeloid cells, and thereby permitting subsequent tissue repair. PMID:26962228

  7. Effects of lentivirus mediated STAT3 silencing on human chronic myeloid leukemia cells and leukemia mice

    PubMed Central

    Jia, Xinyan; Yang, Wenzhong; Han, Jia; Xiong, Hong

    2014-01-01

    Objective: To investigate the effects of lentivirus mediated STAT3 silencing on human chronic myeloid leukemia cells (K562) and the growth of chronic myeloid leukemia mice as well as to explore the potential mechanisms. Methods: Unbtreated K562 cells (CON), blank lentivirus transfected K562 cells (NC) and K562 cells expressing STAT3 siRNA (STAT3 siRNA) were injected into SCID mice to establish the chronic myeloid leukemia model in mice. The growth, peripheral white blood cell count and spleen index in these mice were determined. Results: In vitro experiment showed, when compared with control group, the interference efficiency of STAT3 expression was as high as 97.5% in K562 cells. Western blot assay revealed that the expression of c-Myc, Bcl-xL and Cyclin D1 reduced by 17.01%, 7.3% and 6.82%, respectively, showing significant difference when compared with control group (P < 0.01). These findings were consistent with those from fluorescence quantitative PCR. In vivo experiment showed the body weight of mice reduced progressively and the peripheral white blood cell count increased gradually in control group, accompanied by dragging hind limbs and progressive enlargement of the spleen. The body weight remained unchanged, peripheral white blood cell count reduced gradually and the spleen did not enlarge in mice treated with STAT3 siRNA expressing cells. Conclusion: Lentivirus mediated STAT3 silencing may inhibit the expression of its downstream genes (c-Myc, Bcl-xL and Cyclin D1) related to cell proliferation, apoptosis and cycle to suppress the malignant biological behaviors, and STAT3 silencing also inhibit the leukemogenic potency of K562 cells in mice. PMID:25550912

  8. 5-Azacytidine as Salvage Treatment in Relapsed Myeloid Tumors after Allogeneic Bone Marrow Transplantation

    PubMed Central

    Bolaños-Meade, Javier; Smith, B. Douglas; Gore, Steven D.; McDevitt, Michael A.; Luznik, Leo; Fuchs, Ephraim J.; Jones, Richard J.

    2011-01-01

    Relapse after allogeneic blood or marrow transplantation carries a very poor prognosis. Current strategies for management that include donor lymphocyte infusions (DLIs) and salvage chemotherapies are usually toxic and ineffective. Here we report the outcome of 10 patients with myeloid malignancies that received 5-azacytidine after a failed allogeneic bone marrow transplant. Of the 10 patients, 6 achieved a complete remission, 1 had stable disease, and 3 progressed after a median of 6 cycles administered. Only 1 patient has died (of disease progression), and no flares of graft-versus-host disease (GVHD) were observed with 5-azacytidine. As of latest follow-up, the median overall survival (OS) for the group was 422.5 days (127–1411). These results further suggest that 5-azacytidine is an active agent after failing an allogeneic bone marrow transplant, and prospective studies are warranted. PMID:20951817

  9. Role of HLA-G in tumor escape through expansion of myeloid-derived suppressor cells and cytokinic balance in favor of Th2 versus Th1/Th17.

    PubMed

    Agaugué, Sophie; Carosella, Edgardo D; Rouas-Freiss, Nathalie

    2011-06-30

    The expression of HLA-G by malignant cells has been proposed as a tumor escape mechanism from immunosurveillance. However, although the inhibitory effect of HLA-G on antitumoral immune effectors has been documented in vitro, it remains to be resolved in vivo. In this context, the development of an animal model is now a priority to establish the proof of concept that an HLA-G(+) tumor cell develops and tolerizes the host antitumor immune response in vivo. In the present study, we provide the first in vivo evidence of such a role by a xenotumor model in mice based on the interactions between human HLA-G and the murine paired immunoglobulin-like receptor-B (PIR-B). We demonstrate that human tumor cells expressing HLA-G grow in an immunocompetent host by affecting both innate and adaptive immunity. Expansion of blood myeloid-derived CD11b(+)Gr1(+)PIR-B(+) suppressor cells, loss of peripheral T cells, and cytokinic balance in favor of Th2 versus Th1/Th17 constitute the main mechanisms by which HLA-G promotes tumor expansion. These data demonstrate for the first time that HLA-G plays a crucial role in in vivo tumor evasion. Finally, blocking HLA-G function by a specific Ab inhibits the in vivo development of the tumor, offering a new innovative therapeutic strategy in cancer. PMID:21482709

  10. Cytogenetics of human brain tumors

    SciTech Connect

    Finkernagel, S.W.; Kletz, T.; Day-Salvatore, D.L.

    1994-09-01

    Chromosome studies of 55 brain tumors, including meningiomas, gliomas, astrocyomas and pituatary adenomas, were performed. Primary and first passage cultures were successfully obtained in 75% of these samples with an average of 18 G-banded metaphases analyzed per tumor. 44% of all the brain tumors showed numerical and or structural abnormalities. 46% of the primary and 38% of the first passage cultures showed similar numerical gains/losses and complex karyotypic changes. The most frequent numerical abnormalities (n {ge} 5) included loss of chromosomes 10, 22, and Y. The structural abnormalities most often seen involved 1p, 2, 5, 7, 17q and 19. This is an ongoing study which will attempt to correlate tumor type with specific karyotypic changes and to see if any of the observed chromosomal abnormalities provide prognostic indicators.

  11. Cloning of the novel human myeloid-cell-specific C/EBP-epsilon transcription factor.

    PubMed Central

    Chumakov, A M; Grillier, I; Chumakova, E; Chih, D; Slater, J; Koeffler, H P

    1997-01-01

    Chicken NF-M transcription factor, in cooperation with either c-Myb or v-Myb, is active in the combinatorial activation of myeloid-cell-specific genes in heterologous cell types, such as embryonic fibroblasts. In humans, similar effects were observed with homologous members of the CCAAT/enhancer-binding protein (C/EBP) family of transcriptional regulators, especially the human homolog of chicken NF-M, C/EBP-beta (NF-IL6). However, the NF-IL6 gene is expressed in a variety of nonmyeloid cell types and is strongly inducible in response to inflammatory stimuli, making it an unlikely candidate to have an exclusive role as a combinatorial differentiation switch during myelopoiesis in human cells. By using a reverse transcription-PCR-based approach and a set of primers specific for the DNA-binding domains of highly homologous members of the C/EBP family of transcriptional regulators, we have cloned a novel human gene encoding a member of the C/EBP gene family, identified as the human homolog of CRP1, C/EBP-epsilon. A 1.2-kb cDNA encoding full-length human C/EBP-epsilon was cloned from a promyelocyte-late myeloblast-derived lambda gt11 library. Molecular analysis of the cDNA and genomic clones indicated the presence of two exons encoding a protein with an apparent molecular mass of 32 kDa and a pI of 9.5. Primer extension analysis of C/EBP-epsilon mRNA detected a single major transcription start site approximately 200 bp upstream of the start codon. The putative promoter area is similar to those of several other myeloid-cell-specific genes in that it contains no TATAAA box but has a number of purine-rich stretches with multiple sites for the factors of the Ets family of transcriptional regulators. Northern blot analyses indicated a highly restricted mRNA expression pattern, with the strongest expression occurring in promyelocyte and late-myeloblast-like cell lines. Western blot and immunoprecipitation studies using rabbit anti-C/EBP-epsilon antibodies raised against the N

  12. Bruceine D induces apoptosis in human chronic myeloid leukemia K562 cells via mitochondrial pathway

    PubMed Central

    Zhang, Jian-Ye; Lin, Min-Ting; Tung, Ho-Yi; Tang, Si-Li; Yi, Tao; Zhang, Ya-Zhou; Tang, Yi-Na; Zhao, Zhong-Zhen; Chen, Hu-Biao

    2016-01-01

    Chronic myeloid leukemia (CML), an acquired malignant myeloproliferative disorder of hematopoietic stem cells, is one of the three most common forms of leukemia. In this study, we investigated the effects of bruceine D, which have been isolated from Brucea javanica (L.) Merr. on human chronic myeloid leukemia K562 cells. MTT assay was used to evaluate cell growth inhibition. Flow cytometry was performed to analyze mitochondrial membrane potential (ΔΨm). Western blot was applied to detect expression of cytochrome c, caspases-9, -3, PARP and other proteins. Bruceine D exhibited potent cytotoxicity to K562 cells with IC50 of 6.37 ± 0.39 μM. It led to loss of ΔΨm, release of cytochrome c, activation of caspases-9, -3 and cleavage of PARP, which suggested that bruceine D induced apoptosis of K562 cells through mitochondrial pathway. In addition, bruceine D inhibited the phosphorylation of AKT and ERK. It’s indicative that the potent anticancer activity of bruceine D be related to MAPK and PI3K pathways. PMID:27186433

  13. Midostaurin (PKC412) modulates differentiation and maturation of human myeloid dendritic cells.

    PubMed

    Huang, Yu-Chuen; Shieh, Hui-Ru; Chen, Yu-Jen

    2010-09-01

    Midostaurin, a tyrosine kinase inhibitor, has been shown efficacy against acute myeloid leukemia and various other malignancies in clinical trials. Prior studies indicate midostaurin affects the function of immune cells such as lymphocytes and macrophages. To understand the effect of midostaurin on human myeloid dendritic cells (DCs), we conducted an ex vivo study using immature DCs differentiated from CD14(+) monocytes and further maturated using lipopolysaccharide. Addition of midostaurin to a culture of starting CD14(+) monocytes markedly and dose-dependently reduced DC recovery. Mature DCs differentiating in the presence of midostaurin had fewer, shorter cell projections than those differentiating in the absence of midostaurin. Changes in morphological features characteristic of apoptotic cells were also evident. Moreover, midostaurin affected DC differentiation and maturation patterns; CD83 expression levels decreased, whereas CD14 and CD80 expressions increased. Additionally, DCs derived in the presence of midostaurin possessed a lower endocytotic capacity and less allostimulatory activity on naive CD4(+)CD45(+)RA(+) T cell proliferation than those derived in its absence, suggesting that midostaurin redirects DC differentiation toward a less mature stage and that this effect is not solely due to its cytotoxicity. Whether this effect underlies immune suppression or tolerance to disease treatments with unwanted immune reactions needs further evaluation. PMID:20685248

  14. A robust and rapid xenograft model to assess efficacy of chemotherapeutic agents for human acute myeloid leukemia

    PubMed Central

    Saland, E; Boutzen, H; Castellano, R; Pouyet, L; Griessinger, E; Larrue, C; de Toni, F; Scotland, S; David, M; Danet-Desnoyers, G; Vergez, F; Barreira, Y; Collette, Y; Récher, C; Sarry, J-E

    2015-01-01

    Relevant preclinical mouse models are crucial to screen new therapeutic agents for acute myeloid leukemia (AML). Current in vivo models based on the use of patient samples are not easy to establish and manipulate in the laboratory. Our objective was to develop robust xenograft models of human AML using well-characterized cell lines as a more accessible and faster alternative to those incorporating the use of patient-derived AML cells. Five widely used AML cell lines representing various AML subtypes were transplanted and expanded into highly immunodeficient non-obese diabetic/LtSz-severe combined immunodeficiency IL2Rγcnull mice (for example, cell line-derived xenografts). We show here that bone marrow sublethal conditioning with busulfan or irradiation has equal efficiency for the xenotransplantation of AML cell lines. Although higher number of injected AML cells did not change tumor engraftment in bone marrow and spleen, it significantly reduced the overall survival in mice for all tested AML cell lines. On the basis of AML cell characteristics, these models also exhibited a broad range of overall mouse survival, engraftment, tissue infiltration and aggressiveness. Thus, we have established a robust, rapid and straightforward in vivo model based on engraftment behavior of AML cell lines, all vital prerequisites for testing new therapeutic agents in preclinical studies. PMID:25794133

  15. CD40 dependent exacerbation of immune mediated hepatitis by hepatic CD11b+ Gr-1+ myeloid derived suppressor cells in tumor bearing mice

    PubMed Central

    Kapanadze, Tamar; Medina-Echeverz, José; Gamrekelashvili, Jaba; Weiss, Jonathan M.; Wiltrout, Robert H.; Kapoor, Veena; Hawk, Nga; Terabe, Masaki; Berzofsky, Jay A.; Manns, Michael P.; Wang, Ena; Marincola, Francesco M.; Korangy, Firouzeh; Greten, Tim F.

    2015-01-01

    Immunosuppressive CD11b+Gr-1+ myeloid-derived suppressor cells (MDSC) accumulate in the livers of tumor-bearing mice. We studied hepatic MDSC in two murine models of immune mediated hepatitis. Unexpectedly, treatment of tumor bearing mice with Concanavalin A or α-Galactosylceramide resulted in increased ALT and AST serum levels in comparison to tumor free mice. Adoptive transfer of hepatic MDSC into naïve mice exacerbated Concanavalin A induced liver damage. Hepatic CD11b+Gr-1+ cells revealed a polarized pro-inflammatory gene signature after Concanavalin A treatment. An interferon gamma- dependent up-regulation of CD40 on hepatic CD11b+Gr-1+ cells along with an up-regulation of CD80, CD86, and CD1d after Concanavalin A treatment was observed. Concanavalin A treatment resulted in a loss of suppressor function by tumor-induced CD11b+Gr-1+ MDSC as well as enhanced reactive oxygen species-mediated hepatotoxicity. CD40 knockdown in hepatic MDSC led to increased arginase activity upon Concanavalin A treatment and lower ALT/AST serum levels. Finally, blockade of arginase activity in Cd40−/− tumor-induced myeloid cells resulted in exacerbation of hepatitis and increased reactive oxygen species production in vivo. Our findings indicate that in a setting of acute hepatitis, tumor-induced hepatic MDSC act as pro-inflammatory immune effector cells capable of killing hepatocytes in a CD40-dependent manner. PMID:25616156

  16. Purification, characterization and docking studies of the HIN domain of human myeloid nuclear differentiation antigen (MNDA).

    PubMed

    Li, He; Wang, Zhi-Xin; Wu, Jia-Wei

    2014-05-01

    The HIN domain of myeloid nuclear differentiation antigen (MNDA) was expressed and purified as a monomer using E. coli JM109 as host. The protein interacted with double-stranded DNA at a Kd of 3.15 μM and did not recognize the termini of double-stranded DNA. Isothermal titration calorimetry indicated that the interaction between the protein and double-stranded DNA is mainly mediated by electrostatic attractions and hydrogen bonding. We developed a model to analyze the potential DNA binding site of the MNDA HIN domain. Based on the model, molecular docking and mutation studies suggest that the double-stranded DNA binding site of the protein is different from other HIN-DNA structures. This work facilitates the design of specific drugs against pathogens detected by human MNDA. PMID:24557068

  17. A tumor suppressor function of the Msr1 gene in leukemia stem cells of chronic myeloid leukemia

    PubMed Central

    Chen, Yaoyu; Sullivan, Con; Peng, Cong; Shan, Yi; Hu, Yiguo; Li, Dongguang

    2011-01-01

    We have shown that Alox5 is a critical regulator of leukemia stem cells (LSCs) in a BCR-ABL–induced chronic myeloid leukemia (CML) mouse model, and we hypothesize that the Alox5 pathway represents a major molecular network that regulates LSC function. Therefore, we sought to dissect this pathway by comparing the gene expression profiles of wild type and Alox5−/− LSCs. DNA microarray analysis revealed a small group of candidate genes that exhibited changes in the levels of transcription in the absence of Alox5 expression. In particular, we noted that the expression of the Msr1 gene was upregulated in Alox5−/− LSCs, suggesting that Msr1 suppresses the proliferation of LSCs. Using CML mouse model, we show that Msr1 is downregulated by BCR-ABL and this down-regulation is partially restored by Alox5 deletion, and that Msr1 deletion causes acceleration of CML development. Moreover, Msr1 deletion markedly increases LSC function through its effects on cell cycle progression and apoptosis. We also show that Msr1 affects CML development by regulating the PI3K-AKT pathway and β-Catenin. Together, these results demonstrate that Msr1 suppresses LSCs and CML development. The enhancement of the tumor suppressor function of Msr1 may be of significance in the development of novel therapeutic strategies for CML. PMID:21596859

  18. Tumor-induced myeloid-derived suppressor cell function is independent of IFN-γ and IL-4Rα.

    PubMed

    Sinha, Pratima; Parker, Katherine H; Horn, Lucas; Ostrand-Rosenberg, Suzanne

    2012-08-01

    Myeloid-derived suppressor cells (MDSCs) are present in most cancer patients and experimental animals where they exert a profound immune suppression and are a significant obstacle to immunotherapy. IFN-γ and IL-4 receptor alpha (IL-4Rα) have been implicated as essential molecules for MDSC development and immunosuppressive function. If IFN-γ and IL-4Rα are critical regulators of MDSCs, then they are potential targets for preventing MDSC accumulation or inhibiting MDSC function. Because data supporting a role for IFN-γ and IL-4Rα are not definitive, we have examined MDSCs induced in IFN-γ-deficient, IFN-γR-deficient, and IL-4Rα-deficient mice carrying three C57BL/6-derived (B16 melanoma, MC38 colon carcinoma, and 3LL lung adenocarcinoma), and three BALB/c-derived (4T1 and TS/A mammary carcinomas, and CT26 colon carcinoma) tumors. We report that although MDSCs express functional IFN-γR and IL-4Rα, and have the potential to signal through the STAT1 and STAT6 pathways, respectively, neither IFN-γ nor IL-4Rα impacts the phenotype, accumulation, or T-cell suppressive potency of MDSCs, although IFN-γ and IL-4Rα modestly alter MDSC-macrophage IL-10 crosstalk. Therefore, neither IFN-γ nor IL-4Rα is a key regulator of MDSCs and targeting these molecules is unlikely to significantly alter MDSC accumulation or function. PMID:22673957

  19. L-Arginine depletion blunts anti-tumor T cell responses by inducing myeloid-derived suppressor cells

    PubMed Central

    Fletcher, Matthew; Ramirez, Maria E.; Sierra, Rosa A.; Raber, Patrick; Thevenot, Paul; Al-Khami, Amir A.; Sanchez-Pino, Dulfary; Hernandez, Claudia; Wyczechowska, Dorota D.; Ochoa, Augusto C.; Rodriguez, Paulo C.

    2014-01-01

    Enzymatic depletion of the non-essential amino acid L-Arginine (L-Arg) in cancer patients by the administration of a pegylated form of the catabolic enzyme arginase I (peg-Arg I) has shown some promise as a therapeutic approach. However, L-Arg deprivation also suppresses T-cell responses in tumors. In this study, we sought to reconcile these observations by conducting a detailed analysis of the effects of peg-Arg I on normal T-cells. Strikingly, we found that peg-Arg I blocked proliferation and cell cycle progression in normal activated T-cells without triggering apoptosis or blunting T-cell activation. These effects were associated with an inhibition of aerobic glycolysis in activated T-cells, but not with significant alterations in mitochondrial oxidative respiration, which thereby regulated survival of T-cells exposed to peg-Arg I. Further mechanistic investigations showed that addition of citrulline, a metabolic precursor for L-Arg, rescued the anti-proliferative effects of peg-Arg I on T-cells in vitro. Moreover, serum levels of citrulline increased after in vivo administration of peg-Arg I. In support of the hypothesis that peg-Arg I acted indirectly to block T-cell responses in vivo, peg-Arg I inhibited T-cell proliferation in mice by inducing accumulation of myeloid-derived suppressor cells (MDSC). MDSC induction by peg-Arg I occurred through the general control non-repressed-2 eIF2α kinase. Moreover, we found that peg-Arg I enhanced the growth of tumors in mice in a manner that correlated with higher MDSC numbers. Taken together, our results highlight the risks of the L-Arg-depleting therapy for cancer treatment and suggest a need for co-targeting MDSC in such therapeutic settings. PMID:25406192

  20. Dynamic DNA methylation change in the CpG island region of p15 during human myeloid development.

    PubMed

    Sakashita, K; Koike, K; Kinoshita, T; Shiohara, M; Kamijo, T; Taniguchi, S; Kubota, T

    2001-10-01

    We examined the kenetics of p15 methylation and expression during myeloid development. We treated human cord blood CD34+ cells with either GM-CSF alone or in combination with stem cell factor and followed methylation at this locus using bisulfite genomic sequencing. CD34+ cells were found to be either fully methylated or completely unmethylated at 27 CpG dinucleotide sites in exon 1 and at 18 CpG sites in the promoter region of the p15 gene. A time-course study showed that the percentage of the allelic methylation of p15 CpG island increased to approximately 50% to 60% until 7 days after cytokine stimulation, then decreased to less than 10% after 21 days. The methylation was also observed in bone marrow CD34+ cells exposed to GM-CSF. p15 expression varied inversely with methylation. Expression was negligible or at low levels until 14 days, after which it increased substantially. The frequency of myeloid colony-forming cells in the progeny decreased and myeloid-specific markers increased in the later stages. Based on our observations on cells grown with GM-CSF and 5-aza-2'-deoxycytidine, DNA methylation of the p15 promoter region CpG island appears to be associated with proliferation rather than differentiation of normal human myeloid progenitors. PMID:11602627

  1. Dynamic DNA methylation change in the CpG island region of p15 during human myeloid development

    PubMed Central

    Sakashita, Kazuo; Koike, Kenichi; Kinoshita, Tatsuya; Shiohara, Masaaki; Kamijo, Takehiko; Taniguchi, Shun’ichiro; Kubota, Takeo

    2001-01-01

    We examined the kenetics of p15 methylation and expression during myeloid development. We treated human cord blood CD34+ cells with either GM-CSF alone or in combination with stem cell factor and followed methylation at this locus using bisulfite genomic sequencing. CD34+ cells were found to be either fully methylated or completely unmethylated at 27 CpG dinucleotide sites in exon 1 and at 18 CpG sites in the promoter region of the p15 gene. A time-course study showed that the percentage of the allelic methylation of p15 CpG island increased to approximately 50% to 60% until 7 days after cytokine stimulation, then decreased to less than 10% after 21 days. The methylation was also observed in bone marrow CD34+ cells exposed to GM-CSF. p15 expression varied inversely with methylation. Expression was negligible or at low levels until 14 days, after which it increased substantially. The frequency of myeloid colony-forming cells in the progeny decreased and myeloid-specific markers increased in the later stages. Based on our observations on cells grown with GM-CSF and 5-aza-2′-deoxycytidine, DNA methylation of the p15 promoter region CpG island appears to be associated with proliferation rather than differentiation of normal human myeloid progenitors. PMID:11602627

  2. Mast cells mobilize myeloid-derived suppressor cells and Treg cells in tumor microenvironment via IL-17 pathway in murine hepatocarcinoma model.

    PubMed

    Yang, Zhuoshun; Zhang, Biao; Li, Dapeng; Lv, Meng; Huang, Chunmei; Shen, Guan-Xin; Huang, Bo

    2010-01-01

    Tumor immunosuppression is commonly braided with chronic inflammation during tumor development. However, the relationship between immunosuppression and inflammation in tumor microenvironment is still unclear. We have demonstrated that mast cells are accumulated and exacerbate the inflammation and immunosuppression in tumor microenvironment via SCF/c-kit signaling pathway. Here, we further elucidate the underlying mechanism, which involves both myeloid-derived suppressor cells (MDSCs) and regulatory T (Treg) cells. Our data showed that mast cells mobilized the infiltration of MDSCs to tumor and induced the production of IL-17 by MDSCs; MDSCs-derived IL-17 indirectly attracted Treg cells, enhanced their suppressor function, and induced the IL-9 production by Treg cells; in turn, IL-9 strengthened the survival and protumor effect of mast cells in tumor microenvironment. Our findings disclose a closed loop among mast cells, MDSCs and Treg cells in tumor microenvironment, which provides a new insight into the paralleled developments of inflammation and immunosuppression in tumor microenvironment. Based on these findings, we propose that targeting tumor inflammation might be a potential strategy to reverse the immunosuppression of tumor microenvironment, thus facilitating cancer immunotherapy. PMID:20111717

  3. Bortezomib has little ex vivo activity in chronic myeloid leukemia: individual tumor response testing comparative study in acute and chronic myeloid leukemia

    PubMed Central

    Gil, Lidia; Czyżewski, Krzysztof; Kołodziej, Beata; Kuryło-Rafińska, Beata; Lewandowski, Krzysztof; Gniot, Michał; Lewandowska, Maria; Komarnicki, Mieczysław; Wysocki, Mariusz

    2012-01-01

    Aim of the study Resistance to imatinib is one of the most important issues in treatment of chronic myeloid leukemia (CML) patients. The objective of the study was to analyze the ex vivo drug resistance profile to bortezomib and 22 other antileukemic drugs, including three tyrosine kinase inhibitors (TKIs), in CML in comparison to acute myeloid leukemia (AML). Material and methods A total of 82 patients entered the study, including 36 CML and 46 AML adults. Among CML patients, 19 had advanced disease, 16 were resistant to imatinib, and 6 had ABL-kinase domain mutations. The ex vivo drug resistance profile was studied by the MTT assay. Results CML cells were more resistant than AML blasts to the following drugs: prednisolone, vincristine, doxorubicin, etoposide, melphalan, cytarabine, fludarabine, thiotepa, 4-HOO-cyclophosphamide, thioguanine, bortezomib, topotecan, and clofarabine. CML cells were 2-fold more sensitive to busulfan than AML cells. CML patients with clinical imatinib resistance had higher ex vivo resistance to vincristine, daunorubicin, etoposide, and busulfan. No significant differences to all tested drugs, including TKIs, were observed between CML patients with non-advanced and advanced disease. CML patients with mutation had higher ex vivo resistance to vincristine, idarubicin, thiotepa, and busulfan. Conclusions CML cells are ex vivo more resistant to most drugs than acute myeloid leukemia blasts. Busulfan is more active in CML than AML cells. In comparison to AML cells, bortezomib has little ex vivo activity in CML cells. No differences between CML subgroups in sensitivity to 3 tested TKIs were detected. PMID:23788881

  4. EVI1 Inhibits Apoptosis Induced by Antileukemic Drugs via Upregulation of CDKN1A/p21/WAF in Human Myeloid Cells

    PubMed Central

    Rommer, Anna; Steinmetz, Birgit; Herbst, Friederike; Hackl, Hubert; Heffeter, Petra; Heilos, Daniela; Filipits, Martin; Steinleitner, Katarina; Hemmati, Shayda; Herbacek, Irene; Schwarzinger, Ilse; Hartl, Katharina; Rondou, Pieter; Glimm, Hanno; Karakaya, Kadin; Krämer, Alwin; Berger, Walter; Wieser, Rotraud

    2013-01-01

    Overexpression of ecotropic viral integration site 1 (EVI1) is associated with aggressive disease in acute myeloid leukemia (AML). Despite of its clinical importance, little is known about the mechanism through which EVI1 confers resistance to antileukemic drugs. Here, we show that a human myeloid cell line constitutively overexpressing EVI1 after infection with a retroviral vector (U937_EVI1) was partially resistant to etoposide and daunorubicin as compared to empty vector infected control cells (U937_vec). Similarly, inducible expression of EVI1 in HL-60 cells decreased their sensitivity to daunorubicin. Gene expression microarray analyses of U937_EVI1 and U937_vec cells cultured in the absence or presence of etoposide showed that 77 and 419 genes were regulated by EVI1 and etoposide, respectively. Notably, mRNA levels of 26 of these genes were altered by both stimuli, indicating that EVI1 regulated genes were strongly enriched among etoposide regulated genes and vice versa. One of the genes that were induced by both EVI1 and etoposide was CDKN1A/p21/WAF, which in addition to its function as a cell cycle regulator plays an important role in conferring chemotherapy resistance in various tumor types. Indeed, overexpression of CDKN1A in U937 cells mimicked the phenotype of EVI1 overexpression, similarly conferring partial resistance to antileukemic drugs. PMID:23457546

  5. Emotional Functioning and School Contentment in Adolescent Survivors of Acute Myeloid Leukemia, Infratentorial Astrocytoma, and Wilms Tumor.

    PubMed

    Jóhannsdóttir, Inga M; Moum, Torbjørn; Hjermstad, Marianne J; Wesenberg, Finn; Hjorth, Lars; Schrøder, Henrik; Lähteenmäki, Päivi M; Jónmundsson, Gudmundur; Loge, Jon H

    2011-09-01

    Purpose: Cancer in childhood may disrupt normal developmental processes and cause psychosocial problems in adolescent survivors of childhood cancers (ACCSs). Previous studies report inconsistent findings. Study aims were to assess subjective well-being (SWB), psychological distress, and school contentment in survivors of three dissimilar childhood cancers. Patients and methods: Nordic patients treated for acute myeloid leukemia (AML), infratentorial astrocytoma (IA), and Wilms tumor (WT) in childhood from 1985 to 2001, aged ≥1 year at diagnosis, and aged 13-18 years at the time of study were eligible for this questionnaire-based survey that included items on SWB, psychological distress, school contentment, self-esteem, and personality traits; 65% (151/231) responded. An age-equivalent group from a Norwegian health survey (n=7910) served as controls. Results: The median age of ACCSs was 16 years; 52% were males. ACCSs reported better SWB (p=0.004) and self-esteem (p<0.001). They had fewer social problems in school (p=0.004) and their school contentment tended to be higher than controls. SWB and school contentment were positively influenced by self-esteem. However, ACCSs reported higher levels of psychological distress (p=0.002), mostly attributable to general worrying. No significant differences in outcomes were found across diagnoses, and time since diagnosis did not significantly affect the results. Conclusion: The overall emotional functioning of ACCSs was good, possibly due to changes in their perception of well-being after having survived a life-threatening disease. However, they seemed more worried than their peers. This may cause an additional strain at a vulnerable period in life. PMID:23610734

  6. MRI and MRS of human brain tumors.

    PubMed

    Hou, Bob L; Hu, Jiani

    2009-01-01

    The purpose of this chapter is to provide an introduction to magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) of human brain tumors, including the primary applications and basic terminology involved. Readers who wish to know more about this broad subject should seek out the referenced books (1. Tofts (2003) Quantitative MRI of the brain. Measuring changes caused by disease. Wiley; Bradley and Stark (1999) 2. Magnetic resonance imaging, 3rd Edition. Mosby Inc; Brown and Semelka (2003) 3. MRI basic principles and applications, 3rd Edition. Wiley-Liss) or reviews (4. Top Magn Reson Imaging 17:127-36, 2006; 5. JMRI 24:709-724, 2006; 6. Am J Neuroradiol 27:1404-1411, 2006).MRI is the most popular means of diagnosing human brain tumors. The inherent difference in the magnetic resonance (MR) properties of water between normal tissues and tumors results in contrast differences on the image that provide the basis for distinguishing tumors from normal tissues. In contrast to MRI, which provides spatial maps or images using water signals of the tissues, proton MRS detects signals of tissue metabolites. MRS can complement MRI because the observed MRS peaks can be linked to inherent differences in biochemical profiles between normal tissues and tumors.The goal of MRI and MRS is to characterize brain tumors, including tumor core, edge, edema, volume, types, and grade. The commonly used brain tumor MRI protocol includes T2-weighted images and T1-weighted images taken both before and after the injection of a contrast agent (typically gadolinium: Gd). The commonly used MRS technique is either point-resolved spectroscopy (PRESS) or stimulated echo acquisition mode (STEAM). PMID:19381963

  7. Cancer-Associated Myeloid Regulatory Cells.

    PubMed

    De Vlaeminck, Yannick; González-Rascón, Anna; Goyvaerts, Cleo; Breckpot, Karine

    2016-01-01

    Myeloid cells are critically involved in the pathophysiology of cancers. In the tumor microenvironment (TME), they comprise tumor-associated macrophages (TAMs), neutrophils (TANs), dendritic cells, and myeloid-derived suppressor cells, which are further subdivided into a monocytic subset and a granulocytic subset. Some of these myeloid cells, in particular TAMs and TANs, are divided into type 1 or type 2 cells, according to the paradigm of T helper type 1 or type 2 cells. Type 1-activated cells are generally characterized as cells that aid tumor rejection, while all other myeloid cells are shown to favor tumor progression. Moreover, these cells are often at the basis of resistance to various therapies. Much research has been devoted to study the biology of myeloid cells. This endeavor has proven to be challenging, as the markers used to categorize myeloid cells in the TME are not restricted to particular subsets. Also from a functional and metabolic point of view, myeloid cells share many features. Finally, myeloid cells are endowed with a certain level of plasticity, which further complicates studying them outside their environment. In this article, we challenge the exclusive use of cell markers to unambiguously identify myeloid cell subsets in the TME. We further propose to divide myeloid cells into myeloid regulatory or stimulatory cells according to their pro- or antitumor function, because we contend that for therapeutic purposes it is not targeting the cell subsets but rather targeting their protumor traits; hence, myeloid regulatory cells will push antitumor immunotherapy to the next level. PMID:27065074

  8. Cancer-Associated Myeloid Regulatory Cells

    PubMed Central

    De Vlaeminck, Yannick; González-Rascón, Anna; Goyvaerts, Cleo; Breckpot, Karine

    2016-01-01

    Myeloid cells are critically involved in the pathophysiology of cancers. In the tumor microenvironment (TME), they comprise tumor-associated macrophages (TAMs), neutrophils (TANs), dendritic cells, and myeloid-derived suppressor cells, which are further subdivided into a monocytic subset and a granulocytic subset. Some of these myeloid cells, in particular TAMs and TANs, are divided into type 1 or type 2 cells, according to the paradigm of T helper type 1 or type 2 cells. Type 1-activated cells are generally characterized as cells that aid tumor rejection, while all other myeloid cells are shown to favor tumor progression. Moreover, these cells are often at the basis of resistance to various therapies. Much research has been devoted to study the biology of myeloid cells. This endeavor has proven to be challenging, as the markers used to categorize myeloid cells in the TME are not restricted to particular subsets. Also from a functional and metabolic point of view, myeloid cells share many features. Finally, myeloid cells are endowed with a certain level of plasticity, which further complicates studying them outside their environment. In this article, we challenge the exclusive use of cell markers to unambiguously identify myeloid cell subsets in the TME. We further propose to divide myeloid cells into myeloid regulatory or stimulatory cells according to their pro- or antitumor function, because we contend that for therapeutic purposes it is not targeting the cell subsets but rather targeting their protumor traits; hence, myeloid regulatory cells will push antitumor immunotherapy to the next level. PMID:27065074

  9. 6-Thioguanine-loaded polymeric micelles deplete myeloid-derived suppressor cells and enhance the efficacy of T cell immunotherapy in tumor-bearing mice

    DOE PAGESBeta

    Jeanbart, Laura; Kourtis, Iraklis C.; van der Vlies, André J.; Swartz, Melody A.; Hubbell, Jeffrey A.

    2015-05-16

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells that suppress effector T cell responses and can reduce the efficacy of cancer immunotherapies. We previously showed that ultra-small polymer nanoparticles efficiently drain to the lymphatics after intradermal injection and target antigen-presenting cells, including Ly6chi Ly6g₋monocytic MDSCs (Mo-MDSCs), in skin-draining lymph nodes (LNs) and spleen. Here, we developed ultra-small polymer micelles loaded with 6-thioguanine (MC-TG), a cytotoxic drug used in the treatment of myelogenous leukemia, with the aim of killing Mo-MDSCs in tumor-bearing mice and thus enhancing T cell-mediated anti-tumor responses. We found that 2 days post-injection inmore » tumor-bearing mice (B16-F10 melanoma or E.G7-OVA thymoma), MC-TG depleted Mo-MDSCs in the spleen, Ly6clo Ly6g+ granulocytic MDSCs (G-MDSCs) in the draining LNs, and Gr1int Mo-MDSCs in the tumor. In both tumor models, MC-TG decreased the numbers of circulating Mo- and G-MDSCs, as well as of Ly6chi macrophages, for up to 7 days following a single administration. MDSC depletion was dose dependent and more effective with MC-TG than with equal doses of free TG. Finally, we tested whether this MDSC-depleting strategy might enhance cancer immunotherapies in the B16-F10 melanoma model. We found that MC-TG significantly improved the efficacy of adoptively transferred, OVA-specific CD8+ T cells in melanoma cells expressing OVA. Ultimately, these findings highlight the capacity of MC-TG in depleting MDSCs in the tumor microenvironment and show promise in promoting anti-tumor immunity when used in combination with T cell immunotherapies.« less

  10. Progression and inflammation of human myeloid leukemia induced by ambient PM2.5 exposure.

    PubMed

    Jin, Xiao-Ting; Chen, Mei-Lan; Li, Rui-Jin; An, Quan; Song, Li; Zhao, Yi; Xiao, Hong; Cheng, Long; Li, Zhuo-Yu

    2016-08-01

    PM2.5 (aerodynamic diameter ≤2.5 μm) has been a dominating and ubiquitous air pollutant and has become a global concern. Emerging evidences suggest a positive correlation between PM2.5 and leukemia, but the underlying molecular mechanisms remain unclear and need to be elucidated. Here, we assessed the impacts of PM2.5 on the progression and inflammation of human myeloid leukemia at lower environmental doses and explored the possible pathway. We showed that PM2.5 exposure significantly induced the leukemia cell growth and enhanced the release of inflammatory mediators in both in vitro and in vivo models. Additionally, NF-κB p65 and p-STAT3 were activated in PM2.5-treated leukemia cells, with a concomitant increase in both ROS formation and NADPH oxidase expressions. Strikingly, the supplement of inhibitors, including NAC (ROS), PDTC (NF-κB), or WP1066 (STAT3), contributed to a decline in leukemia cell growth. Furthermore, enhanced expressions of inflammatory cytokines were attenuated by the addition of NAC or PDTC, but not affected by WP1066. This study demonstrates that PM2.5 promotes leukemia progression, identifies a potential intervention target, and provides further understanding of the detrimental effect of PM2.5 exposure on human health. PMID:26486797

  11. A Quantitative Proteomic Approach for Detecting Protein Profiles of Activated Human Myeloid Dendritic Cells

    PubMed Central

    Schlatzer, Daniela M; Sugalski, Julia; Dazard, Jean-Eudes; Chance, Mark R; Anthony, Donald D.

    2011-01-01

    Dendritic cells (DC) direct the magnitude, polarity and effector function of the adaptive immune response. DC express toll-like receptors (TLR), antigen capturing and processing machinery, and costimulatory molecules, which facilitate innate sensing and T cell activation. Once activated, DC can efficiently migrate to lymphoid tissue and prime T cell responses. Therefore, DC play an integral role as mediators of the immune response to multiple pathogens. Elucidating the molecular mechanisms involved in DC activation is therefore central in gaining an understanding of host response to infection. Unfortunately, technical constraints have limited system-wide ‘omic’ analysis of human DC subsets collected ex vivo. Here we have applied novel proteomic approaches to human myeloid dendritic cells (mDCs) purified from 100 milliliters of peripheral blood to characterize specific molecular networks of cell activation at the individual patient level, and have successfully quantified over 700 proteins from individual samples containing as little as 200,000 mDCs. The proteomic and network readouts after ex vivo stimulation of mDCs with TLR3 agonists is measured and verified using flow cytometry. PMID:21945394

  12. Cellular analysis of the histamine H4 receptor in human myeloid cells.

    PubMed

    Capelo, Ricardo; Lehmann, Christoph; Ahmad, Khalil; Snodgrass, Ryan; Diehl, Olaf; Ringleb, Julia; Flamand, Nicolas; Weigert, Andreas; Stark, Holger; Steinhilber, Dieter; Kahnt, Astrid S

    2016-03-01

    The human histamine H4 receptor (H4R) is a Gαi/o-coupled receptor which is mainly expressed on hematopoietic cells. Accordingly, the receptor is implicated in the pathology of various diseases such as autoimmune disorders, bronchial asthma and pruritus. Due to complicated receptor pharmacology, the lack of a reliable antibody and limited availability of primary cells expressing the receptor the physiology of this receptor is still poorly understood. Therefore, we aimed to assess absolute receptor mRNA expression and functionality (intracellular Ca(2+) release) in various human myeloid cell types such as granulocytes, monocytes, macrophages and dendritic cells (DCs). This was put into context with the expression of the H1R and H2R. In addition, the influence of various inflammatory stimuli on H4R expression was investigated in macrophages and monocyte-derived DCs. We found that classically activated macrophages treated with pro-inflammatory stimuli down-regulated histamine receptor mRNA expression as did LPS and zymosan A matured monocyte-derived DCs. In contrast, alternatively activated macrophages (IL-4 or IL-13) upregulated H2R and H4R expression compared to controls. Consistent with existing literature, we found eosinophils to be the major source of the H4R. Since availability of primary eosinophils is limited, we developed a cell model based on the differentiated eosinophilic cell line EOL-1, in which H4R pharmacology and physiology may be studied. PMID:26774453

  13. Metallothionein III (MT3) is a putative tumor suppressor gene that is frequently inactivated in pediatric acute myeloid leukemia by promoter hypermethylation

    PubMed Central

    2014-01-01

    Background Acute myeloid leukemia (AML) is the second most common form of leukemia in children. Aberrant DNA methylation patterns are a characteristic feature in various tumors, including AML. Metallothionein III (MT3) is a tumor suppresser reported to show promoter hypermethylated in various cancers. However, the expression and molecular function of MT3 in pediatric AML is unclear. Methods Eleven human leukemia cell lines and 41 pediatric AML samples and 20 NBM/ITP (Norma bone marrow/Idiopathic thrombocytopenic purpura) control samples were analyzed. Transcription levels of MT3 were evaluated by semi-quantitative and real-time PCR. MT3 methylation status was determined by methylation specific PCR (MSP) and bisulfite genomic sequencing (BSG). The molecular mechanism of MT3 was investigated by apoptosis assays and PCR array analysis. Results The MT3 promoter was hypermethylated in leukemia cell lines. More CpG’s methylated of MT3 was observed 39.0% pediatric AML samples compared to 10.0% NBM controls. Transcription of MT3 was also significantly decreased in AML samples compared to NBM/ITP controls (P < 0.001); patients with methylated MT3 exhibited lower levels of MT3 expression compared to those with unmethylated MT3 (P = 0.049). After transfection with MT3 lentivirus, proliferation was significantly inhibited in AML cells in a dose-dependent manner (P < 0.05). Annexin V assay showed that apoptosis was significantly upregulated MT3-overexpressing AML cells compared to controls. Real-time PCR array analysis revealed 34 dysregulated genes that may be implicated in MT3 overexpression and apoptosis in AML, including FOXO1. Conclusion MT3 may be a putative tumor suppressor gene in pediatric AML. Epigenetic inactivation of MT3 via promoter hypermethylation was observed in both AML cell lines and pediatric AML samples. Overexpression of MT3 may inhibit proliferation and induce apoptosis in AML cells. FOXO1 was dysregulated in MT3-overexpressing cells

  14. STAT3 mutations identified in human hematologic neoplasms induce myeloid malignancies in a mouse bone marrow transplantation model

    PubMed Central

    Couronné, Lucile; Scourzic, Laurianne; Pilati, Camilla; Valle, Véronique Della; Duffourd, Yannis; Solary, Eric; Vainchenker, William; Merlio, Jean-Philippe; Beylot-Barry, Marie; Damm, Frederik; Stern, Marc-Henri; Gaulard, Philippe; Lamant, Laurence; Delabesse, Eric; Merle-Beral, Hélène; Nguyen-Khac, Florence; Fontenay, Michaëla; Tilly, Hervé; Bastard, Christian; Zucman-Rossi, Jessica; Bernard, Olivier A.; Mercher, Thomas

    2013-01-01

    STAT3 protein phosphorylation is a frequent event in various hematologic malignancies and solid tumors. Acquired STAT3 mutations have been recently identified in 40% of patients with T-cell large granular lymphocytic leukemia, a rare T-cell disorder. In this study, we investigated the mutational status of STAT3 in a large series of patients with lymphoid and myeloid diseases. STAT3 mutations were identified in 1.6% (4 of 258) of patients with T-cell neoplasms, in 2.5% (2 of 79) of patients with diffuse large B-cell lymphoma but in no other B-cell lymphoma patients (0 of 104) or patients with myeloid malignancies (0 of 96). Functional in vitro assays indicated that the STAT3Y640F mutation leads to a constitutive phosphorylation of the protein. STA21, a STAT3 small molecule inhibitor, inhibited the proliferation of two distinct STAT3 mutated cell lines. Using a mouse bone marrow transplantation assay, we observed that STAT3Y640F expression leads to the development of myeloproliferative neoplasms with expansion of either myeloid cells or megakaryocytes. Together, these data indicate that the STAT3Y640F mutation leads to constitutive activation of STAT3, induces malignant hematopoiesis in vivo, and may represent a novel therapeutic target in some lymphoid malignancies. PMID:23872306

  15. EVI1 and MDS1/EVI1 Expression During Primary Human Hematopoietic Progenitor Cell Differentiation into Various Myeloid Lineages

    PubMed Central

    Steinleitner, Katarina; Rampetsreiter, Paulina; Köffel, Rene; Ramanathan, Gajalakshmi; Mannhalter, Christine; Strobl, Herbert; Wieser, Rotraud

    2012-01-01

    Background and Aim Overexpression of ecotropic viral integration site 1 (EVI1) is associated with aggressive disease in myeloid leukemia. We therefore studied its expression and function in cluster of differentiation 34 positive (CD 34+) primary human hematopoietic progenitor cells. Materials and Methods CD34+ cells were differentiated into various myeloid lineages using appropriate cytokines. EVI1 expression was measured by quantitative real time reverse transcriptase polymerase chain reaction (qRT-PCR) and intranuclear fluorescence activated cell sorting (FACS). Experimental manipulation of EVI1 levels was achieved using retroviral infection. Results EVI1 mRNA and its variant myelodysplastic syndrome 1 (MDS1)/EVI1, which gives rise to a partially antagonistic protein, were detectable in CD34+ cells, but their levels declined rapidly during differentiation into the granulocytic, monocytic, dendritic, erythroid, and megakaryocytic lineages. Similarly, EVI1 protein levels decreased during myeloid differentiation. Attempts to experimentally express EVI1 in CD34+ and U937 cells indicated that ectopic expression of EVI1 may cause growth arrest, apoptosis and/or senescence of human hematopoietic cells. Conclusion EVI1 is expressed in human hematopoietic progenitor cells, but is down-regulated during differentiation. Ectopic expression of EVI1 may activate cellular safeguards against oncogene activation. PMID:23155256

  16. Modification of sialylation is associated with multidrug resistance in human acute myeloid leukemia.

    PubMed

    Ma, H; Zhou, H; Song, X; Shi, S; Zhang, J; Jia, L

    2015-02-01

    Aberrant cell surface sialylation patterns have been shown to correlate with tumor progression and metastasis. However, the role of sialylation regulation of cancer multidrug resistance (MDR) remains poorly understood. This study investigated sialylation in modification on MDR in acute myeloid leukemia (AML). Using mass spectrometry (MS) analysis, the composition profiling of sialylated N-glycans differed in three pairs of AML cell lines. Real-time PCR showed the differential expressional profiles of 20 sialyltransferase (ST) genes in the both AML cell lines and bone marrow mononuclear cells (BMMCs) of AML patients. The expression levels of ST3GAL5 and ST8SIA4 were detected, which were overexpressed in HL60 and HL60/adriamycin-resistant (ADR) cells. The altered levels of ST3GAL5 and ST8SIA4 were found in close association with the MDR phenotype changing of HL60 and HL60/ADR cells both in vitro and in vivo. Further data demonstrated that manipulation of these two genes' expression modulated the activity of phosphoinositide-3 kinase (PI3K)/Akt signaling pathway and its downstream target thus regulated the proportionally mutative expression of P-glycoprotein (P-gp) and MDR-related protein 1 (MRP1), both of which are known to be involved in MDR. Blocking the PI3K/Akt pathway by its specific inhibitor LY294002 or by Akt small interfering RNA resulted in the reduced chemosensitivity of HL60/ADR cells. Therefore, this study indicated that sialylation involved in the development of MDR of AML cells probably through ST3GAL5 or ST8SIA4 regulating the activity of PI3K/Akt signaling and the expression of P-gp and MRP1. PMID:24531716

  17. EM23, A Natural Sesquiterpene Lactone from Elephantopus mollis, Induces Apoptosis in Human Myeloid Leukemia Cells through Thioredoxin- and Reactive Oxygen Species-Mediated Signaling Pathways.

    PubMed

    Li, Hongyu; Li, Manmei; Wang, Guocai; Shao, Fangyuan; Chen, Wenbo; Xia, Chao; Wang, Sheng; Li, Yaolan; Zhou, Guangxiong; Liu, Zhong

    2016-01-01

    Elephantopus mollis (EM) is a traditional herbal medicine with multiple pharmacological activities. However, the efficacy of EM in treating human leukemia is currently unknown. In the current study, we report that EM23, a natural sesquiterpene lactone isolated from EM, inhibits the proliferation of human chronic myeloid leukemia (CML) K562 cells and acute myeloid leukemia (AML) HL-60 cells by inducing apoptosis. Translocation of membrane-associated phospholipid phosphatidylserines, changes in cell morphology, activation of caspases, and cleavage of PARP were concomitant with this inhibition. The involvement of the mitochondrial pathway in EM23-mediated apoptosis was suggested by observed disruptions in mitochondrial membrane potential. Mechanistic studies indicated that EM23 caused a marked increase in the level of reactive oxygen species (ROS). Pretreatment with N-acetyl-L-cysteine, a ROS scavenger, almost fully reversed EM23-mediated apoptosis. In EM23-treated cells, the expression levels of thioredoxin (Trx) and thioredoxinreductase (TrxR), two components of the Trx system involved in maintaining cellular redox homeostasis, were significantly down-regulated. Concomitantly, Trx regulated the activation of apoptosis signal-regulating kinase 1 (ASK1) and its downstream regulatory targets, the p38, JNK, and ERK MAPKs. EM23-mediated activation of ASK1/MAPKs was significantly inhibited in the presence of NAC. Furthermore, tumor necrosis factor alpha (TNF-α)-mediated activation of nuclear factor-κB (NF-κB) was suppressed by EM23, as suggested by the observed blockage of p65 nuclear translocation, phosphorylation, and reversion of IκBα degradation following EM23 treatment. Taken together, these results provide important insights into the anticancer activities of the EM component EM23 against human CML K562 cells and AML HL-60 cells. PMID:27064563

  18. EM23, A Natural Sesquiterpene Lactone from Elephantopus mollis, Induces Apoptosis in Human Myeloid Leukemia Cells through Thioredoxin- and Reactive Oxygen Species-Mediated Signaling Pathways

    PubMed Central

    Li, Hongyu; Li, Manmei; Wang, Guocai; Shao, Fangyuan; Chen, Wenbo; Xia, Chao; Wang, Sheng; Li, Yaolan; Zhou, Guangxiong; Liu, Zhong

    2016-01-01

    Elephantopus mollis (EM) is a traditional herbal medicine with multiple pharmacological activities. However, the efficacy of EM in treating human leukemia is currently unknown. In the current study, we report that EM23, a natural sesquiterpene lactone isolated from EM, inhibits the proliferation of human chronic myeloid leukemia (CML) K562 cells and acute myeloid leukemia (AML) HL-60 cells by inducing apoptosis. Translocation of membrane-associated phospholipid phosphatidylserines, changes in cell morphology, activation of caspases, and cleavage of PARP were concomitant with this inhibition. The involvement of the mitochondrial pathway in EM23-mediated apoptosis was suggested by observed disruptions in mitochondrial membrane potential. Mechanistic studies indicated that EM23 caused a marked increase in the level of reactive oxygen species (ROS). Pretreatment with N-acetyl-L-cysteine, a ROS scavenger, almost fully reversed EM23-mediated apoptosis. In EM23-treated cells, the expression levels of thioredoxin (Trx) and thioredoxinreductase (TrxR), two components of the Trx system involved in maintaining cellular redox homeostasis, were significantly down-regulated. Concomitantly, Trx regulated the activation of apoptosis signal-regulating kinase 1 (ASK1) and its downstream regulatory targets, the p38, JNK, and ERK MAPKs. EM23-mediated activation of ASK1/MAPKs was significantly inhibited in the presence of NAC. Furthermore, tumor necrosis factor alpha (TNF-α)-mediated activation of nuclear factor-κB (NF-κB) was suppressed by EM23, as suggested by the observed blockage of p65 nuclear translocation, phosphorylation, and reversion of IκBα degradation following EM23 treatment. Taken together, these results provide important insights into the anticancer activities of the EM component EM23 against human CML K562 cells and AML HL-60 cells. PMID:27064563

  19. Human myeloid plasma membrane glycoprotein CD13 (gp150) is identical to aminopeptidase N.

    PubMed Central

    Look, A T; Ashmun, R A; Shapiro, L H; Peiper, S C

    1989-01-01

    To determine the primary structure of CD13, a 150-kD cell surface glycoprotein originally identified on subsets of normal and malignant human myeloid cells, we isolated the complete sequences encoding the polypeptide in overlapping complementary DNA (cDNA) clones. The authenticity of our cDNA clones was demonstrated by the ability of the coding sequences, subcloned in a retroviral expression vector, to mediate expression of bona fide CD13 molecules at the surface of transfected mouse fibroblasts. The nucleotide sequence predicts a 967 amino acid integral membrane protein with a single, 24 amino acid hydrophobic segment near the amino terminus. Amino-terminal protein sequence analysis of CD13 molecules indicated that the hydrophobic segment is not cleaved, but rather serves as both a signal for membrane insertion and as a stable membrane-spanning segment. The remainder of the molecule consists of a large extracellular carboxyterminal domain, which contains a pentapeptide consensus sequence characteristic of members of the zinc-binding metalloprotease superfamily. Sequence comparisons with known enzymes of this class revealed that CD13 is identical to aminopeptidase N, a membrane-bound glycoprotein thought to be involved in the metabolism of regulatory peptides by diverse cell types, including small intestinal and renal tubular epithelial cells, macrophages, granulocytes, and synaptic membranes prepared from cells of the central nervous system. Images PMID:2564851

  20. GPR56 identifies primary human acute myeloid leukemia cells with high repopulating potential in vivo.

    PubMed

    Pabst, Caroline; Bergeron, Anne; Lavallée, Vincent-Philippe; Yeh, Jonathan; Gendron, Patrick; Norddahl, Gudmundur L; Krosl, Jana; Boivin, Isabel; Deneault, Eric; Simard, Jessica; Imren, Suzan; Boucher, Geneviève; Eppert, Kolja; Herold, Tobias; Bohlander, Stefan K; Humphries, Keith; Lemieux, Sébastien; Hébert, Josée; Sauvageau, Guy; Barabé, Frédéric

    2016-04-21

    Acute myeloid leukemia (AML) is a genetically heterogeneous hematologic malignancy, which is initiated and driven by a rare fraction of leukemia stem cells (LSCs). Despite the difficulties of identifying a common LSC phenotype, there is increasing evidence that high expression of stem cell gene signatures is associated with poor clinical outcome. Identification of functionally distinct subpopulations in this disease is therefore crucial to dissecting the molecular machinery underlying LSC self-renewal. Here, we combined next-generation sequencing technology with in vivo assessment of LSC frequencies and identified the adhesion G protein-coupled receptor 56 (GPR56) as a novel and stable marker for human LSCs for the majority of AML samples. High GPR56 expression was significantly associated with high-risk genetic subgroups and poor outcome. Analysis of GPR56 in combination with CD34 expression revealed engraftment potential of GPR56(+)cells in both the CD34(-)and CD34(+)fractions, thus defining a novel LSC compartment independent of the CD34(+)CD38(-)LSC phenotype. PMID:26834243

  1. α-Tomatine inhibits growth and induces apoptosis in HL-60 human myeloid leukemia cells.

    PubMed

    Huang, Huarong; Chen, Shaohua; Van Doren, Jeremiah; Li, Dongli; Farichon, Chelsea; He, Yan; Zhang, Qiuyan; Zhang, Kun; Conney, Allan H; Goodin, Susan; Du, Zhiyun; Zheng, Xi

    2015-06-01

    α‑Tomatine is a glycoalkaloid that occurs naturally in tomatoes (Lycopersicon esculentum). In the present study, the effects of α‑tomatine on human myeloid leukemia HL‑60 cells were investigated. Treatment of HL‑60 cells with α‑tomatine resulted in growth inhibition and apoptosis in a concentration‑dependent manner. Tomatidine, the aglycone of tomatine had little effect on the growth and apoptosis of HL‑60 cells. Growth inhibition and apoptosis induced by α‑tomatine in HL‑60 cells was partially abrogated by addition of cholesterol indicating that interactions between α‑tomatine and cell membrane‑associated cholesterol may be important in mediating the effect of α‑tomatine. Activation of nuclear factor‑κB by the phorbol ester, 12‑O‑tetradecanoylphorbol‑13‑acetate failed to prevent apoptosis in HL‑60 cells treated with α‑tomatine. In animal experiments, it was found that treatment of mice with α‑tomatine inhibited the growth of HL‑60 xenografts in vivo. Results from the present study indicated that α‑tomatine may have useful anti‑leukemia activities. PMID:25625536

  2. Myeloid leukemia risk assessment and dynamics of the granulocytopoietic system in acutely and continuously irradiated humans: modeling approach.

    PubMed

    Smirnova, O A

    2015-05-01

    A dynamic modeling approach to the risk assessment of radiogenic myeloid leukemia is proposed. A basic tool of this approach is a biologically motivated mathematical model of the granulocytopoietic system, which is capable of predicting the dynamics of blood granulocytes and bone marrow granulocytopoietic cells in acutely and chronically irradiated humans. The performed modeling studies revealed that the dose dependence of the scaled maximal concentration of bone marrow granulocytopoietic cells with radiation-induced changes, which make a cell premalignant, and the dose dependence of the scaled integral of the concentration of these cells over the period of the response of the granulocytopoietic system to acute irradiation conform to the dose dependence of excess relative risk for myeloid leukemia among atomic bomb survivors in a wide range of doses and in a range of comparatively low doses, respectively. Additionally, the dose dependence of the scaled integral of the concentration of these cells over the period of the response of the granulocytopoietic system to continuous irradiation with the dose rate and durations, which were used in brachytherapy, conforms to the dose dependence of excess relative risk for leukemia among the respective groups of exposed patients. These modeling findings demonstrate the potential to use the proposed modeling approach for predicting the excess relative risk for myeloid leukemia among humans exposed to various radiation regimes. Obviously, this is especially important in the assessment of the risks for radiogenic myeloid leukemia among people residing in contaminated areas after an accident or explosion of a radiological device, among astronauts on long-term space missions, as well as among patients treated with radiotherapy. PMID:25811147

  3. Induction of cytosine arabinoside-resistant human myeloid leukemia cell death through autophagy regulation by hydroxychloroquine.

    PubMed

    Kim, Yundeok; Eom, Ju-In; Jeung, Hoi-Kyung; Jang, Ji Eun; Kim, Jin Seok; Cheong, June-Won; Kim, Young Sam; Min, Yoo Hong

    2015-07-01

    We investigated the effects of the autophagy inhibitor hydroxychloroquine (HCQ) on cell death of cytosine arabinoside (Ara-C)-resistant human acute myeloid leukemia (AML) cells. Ara-C-sensitive (U937, AML-2) and Ara-C-resistant (U937/AR, AML-2/AR) human AML cell lines were used to evaluate HCQ-regulated cytotoxicity, autophagy, and apoptosis as well as effects on cell death-related signaling pathways. We found that HCQ-induced dose- and time-dependent cell death in Ara-C-resistant cells compared to Ara-C-sensitive cell lines. The extent of cell death and features of HCQ-induced autophagic markers including increase in microtubule-associated protein light chain 3 (LC3) I conversion to LC3-II, beclin-1, ATG5, as well as green fluorescent protein-LC3 positive puncta and autophagosome were remarkably greater in U937/AR cells. Also, p62/SQSTM1 was increased in response to HCQ. p62/SQSTM1 protein interacts with both LC3-II and ubiquitin protein and is degraded in autophagosomes. Therefore, a reduction of p62/SQSTM1 indicates increased autophagic degradation, whereas an increase of p62/SQSTM1 by HCQ indicates inhibited autophagic degradation. Knock down of p62/SQSTM1 using siRNA were prevented the HCQ-induced LC3-II protein level as well as significantly reduced the HCQ-induced cell death in U937/AR cells. Also, apoptotic cell death and caspase activation in U937/AR cells were increased by HCQ, provided evidence that HCQ-induced autophagy blockade. Taken together, our data show that HCQ-induced apoptotic cell death in Ara-C-resistant AML cells through autophagy regulation. PMID:26211587

  4. Tadalafil Reduces Myeloid-Derived Suppressor Cells and Regulatory T Cells and Promotes Tumor Immunity in Patients with Head and Neck Squamous Cell Carcinoma

    PubMed Central

    Vella, Jennifer L.; Reis, Isildinha M.; De la fuente, Adriana C.; Gomez, Carmen; Sargi, Zoukaa; Nazarian, Ronen; Califano, Joseph; Borrello, Ivan

    2015-01-01

    Purpose Myeloid-derived suppressor cells (MDSC) and regulatory T cells (Treg) play a key role in the progression of head and neck squamous cell carcinoma (HNSCC). On the basis of our preclinical data demonstrating that phosphodiesterase-5 (PDE5) inhibition can modulate these cell populations, we evaluated whether the PDE5 inhibitor tadalafil can revert tumor-induced immunosuppression and promote tumor immunity in patients with HNSCC. Experimental Design First, we functionally and phenotypically characterized MDSCs in HNSCCs and determined, retrospectively, whether their presence at the tumor site correlates with recurrence. Then, we performed a prospective single-center, double-blinded, randomized, three-arm study in which patients with HNSCC undergoing definitive surgical resection of oral and oropharyngeal tumors were treated with tadalafil 10 μg/day, 20 μg/day, or placebo for at least 20 days preoperatively. Blood and tumor MDSC and Treg presence and CD8+ T-cell reactivity to tumor antigens were evaluated before and after treatment. Results MDSCs were characterized in HNSCC and their intratumoral presence significantly correlates with recurrence. Tadalafil treatment was well tolerated and significantly reduced both MDSCs and Treg concentrations in the blood and in the tumor (P < 0.05). In addition, the concentration of blood CD8+ T cells reactive to autologous tumor antigens significantly increased after treatment (P < 0.05). Tadalafil immunomodulatory activity was maximized at an intermediate dose but not at higher doses. Mechanistic analysis suggests a possible off-target effect on PDE11 at high dosages that, by increasing intracellular cAMP, may negatively affect antitumor immunity. Conclusions Tadalafil seems to beneficially modulate the tumor micro- and macro-environment in patients with HNSCC by lowering MDSCs and Tregs and increasing tumor-specific CD8+ T cells in a dose-dependent fashion. PMID:25320361

  5. Aminoacyl-tRNA synthetase-interacting multifunctional protein 1 suppresses tumor growth in breast cancer-bearing mice by negatively regulating myeloid-derived suppressor cell functions.

    PubMed

    Hong, Hye-Jin; Lim, Hui Xuan; Song, Ju Han; Lee, Arim; Kim, Eugene; Cho, Daeho; Cohen, Edward P; Kim, Tae Sung

    2016-01-01

    Myeloid-derived suppressor cells (MDSCs) are one of the most important cell types that contribute to negative regulation of immune responses in the tumor microenvironment. Recently, aminoacyl-tRNA synthetase-interacting multifunctional protein 1 (AIMP1), a novel pleiotropic cytokine, was identified as an antitumor protein that inhibits angiogenesis and induces antitumor responses. However, the effect of AIMP1 on MDSCs in the tumor environment remains unclear. In the present study, we demonstrated that AIMP1 significantly inhibited tumor growth in 4T1 breast cancer-bearing mice and reduced MDSCs population of tumor sites and spleens of tumor-bearing mice. AIMP1 reduced expansion of MDSCs from bone marrow-derived cells in the tumor-conditioned media. AIMP1 also negatively regulated suppressive activities of MDSCs by inhibiting IL-6 and NO production, and Arg-1 expression. Furthermore, treatment of breast cancer-bearing mice with AIMP1 decreased the capacity of MDSCs to suppress T cell proliferation and Treg cell induction. Western blot and inhibition experiments showed that downregulation of MDSCs functions by AIMP1 may result from attenuated activation of STATs, Akt, and ERK. These findings indicate that AIMP1 plays an essential role in negative regulation of suppressive functions of MDSCs. Therefore, it has a significant potential as a therapeutic agent for cancer treatment. PMID:26613952

  6. A human promyelocytic-like population is responsible for the immune suppression mediated by myeloid-derived suppressor cells

    PubMed Central

    Solito, Samantha; Falisi, Erika; Diaz-Montero, Claudia Marcela; Doni, Andrea; Pinton, Laura; Rosato, Antonio; Francescato, Samuela; Basso, Giuseppe; Zanovello, Paola; Onicescu, Georgiana; Garrett-Mayer, Elizabeth; Montero, Alberto J.; Bronte, Vincenzo

    2011-01-01

    We recently demonstrated that human BM cells can be treated in vitro with defined growth factors to induce the rapid generation of myeloid-derived suppressor cells (MDSCs), hereafter defined as BM-MDSCs. Indeed, combination of G-CSF + GM-CSF led to the development of a heterogeneous mixture of immature myeloid cells ranging from myeloblasts to band cells that were able to suppress alloantigen- and mitogen-stimulated T lymphocytes. Here, we further investigate the mechanism of suppression and define the cell subset that is fully responsible for BM-MDSC–mediated immune suppression. This population, which displays the structure and markers of promyelocytes, is however distinct from physiologic promyelocytes that, instead, are devoid of immuosuppressive function. In addition, we demonstrate that promyelocyte-like cells proliferate in the presence of activated lymphocytes and that, when these cells exert suppressive activity, they do not differentiate but rather maintain their immature phenotype. Finally, we show that promyelocyte-like BM-MDSCs are equivalent to MDSCs present in the blood of patients with breast cancer and patients with colorectal cancer and that increased circulating levels of these immunosuppressive myeloid cells correlate with worse prognosis and radiographic progression. PMID:21734236

  7. Potential role of curcumin and taurine combination therapy on human myeloid leukemic cells propagated in vitro.

    PubMed

    El-Houseini, Motawa E; Refaei, Mohammed Osman; Amin, Ahmed Ibrahim; Abol-Ftouh, Mahmoud A

    2013-10-01

    Curcumin and taurine are natural products that have been used in this study evaluating their therapeutic effect on myeloid leukemic cells propagated in vitro. Sixty patients with myeloid leukemia and 30 healthy volunteers were enrolled in the study. All patient groups were admitted to the Medical Oncology Department of the National Cancer Institute, Cairo University. There were statistically significant differences between treated leukemic cells compared to normal mononuclear leukocytes in cell density, interferon-γ and immunophenotypic profile, mainly CD4+, CD8 + and CD25+. This work highlights the possibility of using curcumin and taurine as a potential useful therapy in the management of patients suffering from chronic and acute myeloid leukemias. PMID:23418874

  8. PTEN: Multiple Functions in Human Malignant Tumors

    PubMed Central

    Milella, Michele; Falcone, Italia; Conciatori, Fabiana; Cesta Incani, Ursula; Del Curatolo, Anais; Inzerilli, Nicola; Nuzzo, Carmen M. A.; Vaccaro, Vanja; Vari, Sabrina; Cognetti, Francesco; Ciuffreda, Ludovica

    2015-01-01

    PTEN is the most important negative regulator of the PI3K signaling pathway. In addition to its canonical, PI3K inhibition-dependent functions, PTEN can also function as a tumor suppressor in a PI3K-independent manner. Indeed, the PTEN network regulates a broad spectrum of biological functions, modulating the flow of information from membrane-bound growth factor receptors to nuclear transcription factors, occurring in concert with other tumor suppressors and oncogenic signaling pathways. PTEN acts through its lipid and protein phosphatase activity and other non-enzymatic mechanisms. Studies conducted over the past 10 years have expanded our understanding of the biological role of PTEN, showing that in addition to its ability to regulate proliferation and cell survival, it also plays an intriguing role in regulating genomic stability, cell migration, stem cell self-renewal, and tumor microenvironment. Changes in PTEN protein levels, location, and enzymatic activity through various molecular mechanisms can generate a continuum of functional PTEN levels in inherited syndromes, sporadic cancers, and other diseases. PTEN activity can indeed, be modulated by mutations, epigenetic silencing, transcriptional repression, aberrant protein localization, and post-translational modifications. This review will discuss our current understanding of the biological role of PTEN, how PTEN expression and activity are regulated, and the consequences of PTEN dysregulation in human malignant tumors. PMID:25763354

  9. Molecular Pathways: Myeloid Complicity in Cancer

    PubMed Central

    Stromnes, Ingunn M.; Greenberg, Philip D.; Hingorani, Sunil R.

    2014-01-01

    Cancer-induced inflammation results in accumulation of myeloid cells. It has become increasingly evident that tumor-dependent factors condition myeloid cells toward an immunosuppressive and pro-tumorigenic phenotype. These myeloid cells include progenitors and progeny of monocytes, granulocytes, macrophages, and dendritic cells. Myeloid cells are not simply bystanders in malignancy or barometers of disease burden. Reflecting their dynamic and plastic nature, myeloid cells manifesta continuum of cellular differentiation and are intimately involved at all stages of neoplastic progression. They can promote tumorigenesis through both immune-dependent and independent mechanisms and can dictate response to therapies. A greater understanding of the inherent plasticity and relationships among myeloid subsets is needed to inform therapeutic targeting. New clinical trials are being designed to modulate the activities of myeloid cells in cancer, which may be essential to maximize the efficacy of both conventional cytotoxic and immune-based therapies for solid tumors. PMID:25047706

  10. New Mouse Models to Investigate the Efficacy of Drug Combinations in Human Chronic Myeloid Leukemia.

    PubMed

    Lin, Hanyang; Woolfson, Adrian; Jiang, Xiaoyan

    2016-01-01

    Chronic myeloid leukemia (CML) comprises a simple and effective paradigm for generating new insights into the cellular origin, pathogenesis, and treatment of many types of human cancer. In particular, mouse models of CML have greatly facilitated the understanding of the underlying molecular mechanisms and pathogenesis of this disease and have led to the identification of new drug targets that in some cases offer the possibility of functional cure. There are currently three established CML mouse models: the BCR-ABL transgenic model, the BCR-ABL retroviral transduction/transplantation model, and the xenotransplant immunodeficient model. Each has its own unique advantages and disadvantages. Depending on the question of interest, some models may be more appropriate than others. In this chapter, we describe a newly developed xenotransplant mouse model to determine the efficacy of novel therapeutic agents, either alone or in combination. The model facilitates the evaluation of the frequency of leukemic stem cells with long-term leukemia-initiating activity, a critical subcellular population that causes disease relapse and progression, through the utilization of primary CD34(+) CML stem/progenitor cells obtained from CML patients at diagnosis and prior to drug treatment. We have also investigated the effectiveness of new combination treatment strategies designed to prevent the development of leukemia in vivo using BCR-ABL (+) blast crisis cells as a model system. These types of in vivo studies are important for the prediction of individual patient responses to drug therapy, and have the potential to facilitate the design of personalized combination therapy strategies. PMID:27581149

  11. [Apoptosis-inducing effects of brucine on human chronic myeloid leukemia cell line K562].

    PubMed

    Wang, Hai-Li; We, Wu; Ji, Ai-Fan; Shen, Xu-Liang; Zhang, Guo-Xiang; Zhang, Mei-Xiang; Zhai, Chun-Yan

    2011-06-01

    To investigate the apoptosis-induction effect of brucine on human chronic myeloid leukemia cell line K562 cells, K562 cells were exposed to various dosages of brucine. MTT method was used to assayed the growth inhibition effect of brucine on K562 cells. The apoptosis of K562 cells was detected by acridine orange/ethidium bromide (AO/EB) double staining, Annexin-V/PI double labeling method and DNA agarose gel electrophoresis. The results showed that brucine could remarkably inhibit the K562 cell growth in a concentration-dependent and time-dependent manners at the range of 50 to 400 µg/ml, and its most significant inhibition was observed at 400 µg/ml for 72 hours and the inhibition rate was 94.0%. Staining of cells with AO-EB revealed that brucine induced nuclear chromatin condensation. After the K562 cells were treated with the brucine of 400 µg/ml for 72 hours, the most of the nucleus were orange stained and condensation-like or bead-like showing apoptotic morphology. The K562 cells treated with brucine of different concentrations (50, 100, 200, 400, 800 µg/ml) for 72 hours, Annexin-V/PI detection showed brucine could induce apoptosis of K562 cells, and apoptosis rate increased gradually with increasing concentration of drugs. The K562 cells treated with brucine of 400 µg/ml for 72 hours displayed typical ladder strap in DNA gel electrophoresis. It is concluded that brucine can efficiently inhibit cell growth and induce apoptosis of K562 cells with dose-dependent manner in concentrations of 50 - 400 µg/ml. PMID:21729538

  12. SIK inhibition in human myeloid cells modulates TLR and IL-1R signaling and induces an anti-inflammatory phenotype.

    PubMed

    Lombardi, Maria Stella; Gilliéron, Corine; Dietrich, Damien; Gabay, Cem

    2016-05-01

    Macrophage polarization into a phenotype producing high levels of anti-inflammatory IL-10 and low levels of proinflammatory IL-12 and TNF-α cytokines plays a pivotal role in the resolution of inflammation. Salt-inducible kinases synergize with TLR signaling to restrict the formation of these macrophages. The expression and function of salt-inducible kinase in primary human myeloid cells are poorly characterized. Here, we demonstrated that the differentiation from peripheral blood monocytes to macrophages or dendritic cells induced a marked up-regulation of salt-inducible kinase protein expression. With the use of 2 structurally unrelated, selective salt-inducible kinase inhibitors, HG-9-91-01 and ARN-3236, we showed that salt-inducible kinase inhibition significantly decreased proinflammatory cytokines (TNF-α, IL-6, IL-1β, and IL-12p40) and increased IL-10 secretion by human myeloid cells stimulated with TLR2 and-4 agonists. Differently than in mouse cells, salt-inducible kinase inhibition did not enhance IL-1Ra production in human macrophages. Salt-inducible kinase inhibition blocked several markers of proinflammatory (LPS + IFN-γ)-polarized macrophages [M(LPS + IFN-γ)] and induced a phenotype characterized by low TNF-α/IL-6/IL-12p70 and high IL-10. The downstream effects observed with salt-inducible kinase inhibitors on cytokine modulation correlated with direct salt-inducible kinase target (CREB-regulated transcription coactivator 3 and histone deacetylase 4) dephosphorylation in these cells. More importantly, we showed for the first time that salt-inducible kinase inhibition decreases proinflammatory cytokines in human myeloid cells upon IL-1R stimulation. Altogether, our results expand the potential therapeutic use of salt-inducible kinase inhibitors in immune-mediated inflammatory diseases. PMID:26590148

  13. Monocytic CCR2+ Myeloid Derived Suppressor Cells Promote Immune Escape By Limiting Activated CD8 T Cell Infiltration Into The Tumor Microenvironment

    PubMed Central

    Lesokhin, Alexander M.; Hohl, Tobias M.; Kitano, Shigehisa; Cortez, Czrina; Hirschhorn-Cymerman, Daniel; Avogadri, Francesca; Rizzuto, Gabrielle A.; Lazarus, John J.; Pamer, Eric G.; Houghton, Alan N.; Merghoub, Taha; Wolchok, Jedd D.

    2011-01-01

    Myeloid derived suppressor cells (MDSC) are a heterogeneous population of cells that accumulate during tumor formation, facilitate immune escape and enable tumor progression. MDSC are important contributors to the development of an immunosuppressive tumor microenvironment that blocks the action of cytotoxic anti-tumor T effector cells. Heterogeneity in these cells poses a significant barrier to studying the in vivo contributions of individual MDSC subtypes. Herein, we demonstrate that granulocyte-macrophage colony stimulating factor (GM-CSF), a cytokine critical for the numeric and functional development of MDSC populations, promotes expansion of a monocyte-derived MDSC population characterized by expression of CD11b and the chemokine receptor CCR2. Utilizing a toxin mediated ablation strategy to target CCR2-expressing cells, we show that these monocytic MDSCs regulate entry of activated CD8 T cells into the tumor site, thereby limiting the efficacy of immunotherapy. Our results argue that therapeutic targeting of monocytic MDSCs would enhance outcomes in immunotherapy. PMID:22174368

  14. Myeloid derived suppressor cells

    PubMed Central

    Waldron, Todd J.; Quatromoni, Jon G.; Karakasheva, Tatiana A.; Singhal, Sunil; Rustgi, Anil K.

    2013-01-01

    The goal of achieving measurable response with cancer immunotherapy requires counteracting the immunosuppressive characteristics of tumors. One of the mechanisms that tumors utilize to escape immunosurveillance is the activation of myeloid derived suppressor cells (MDSCs). Upon activation by tumor-derived signals, MDSCs inhibit the ability of the host to mount an anti-tumor immune response via their capacity to suppress both the innate and adaptive immune systems. Despite their relatively recent discovery and characterization, anti-MDSC agents have been identified, which may improve immunotherapy efficacy. PMID:23734336

  15. Human mesenchymal and murine stromal cells support human lympho-myeloid progenitor expansion but not maintenance of multipotent haematopoietic stem and progenitor cells.

    PubMed

    Radtke, Stefan; Görgens, André; Liu, Bing; Horn, Peter A; Giebel, Bernd

    2016-02-16

    A major goal in haematopoietic stem cell (HSC) research is to define conditions for the expansion of HSCs or multipotent progenitor cells (MPPs). Since human HSCs/MPPs cannot be isolated, NOD/SCID repopulating cell (SRC) assays emerged as the standard for the quantification of very primitive haematopoietic cell. However, in addition to HSCs/MPPs, lympho-myeloid primed progenitors (LMPPs) were recently found to contain SRC activities, challenging this assay as clear HSC/MPP readout. Because our revised model of human haematopoiesis predicts that HSCs/MPPs can be identified as CD133(+)CD34(+) cells containing erythroid potentials, we investigated the potential of human mesenchymal and conventional murine stromal cells to support expansion of HSCs/MPPs. Even though all stromal cells supported expansion of CD133(+)CD34(+) progenitors with long-term myeloid and long-term lymphoid potentials, erythroid potentials were exclusively found within erythro-myeloid CD133(low)CD34(+) cell fractions. Thus, our data demonstrate that against the prevailing assumption co-cultures on human mesenchymal and murine stromal cells neither promote expansion nor maintenance of HSCs and MPPs. PMID:26818432

  16. PU.1 downregulation in murine radiation-induced acute myeloid leukaemia (AML): from molecular mechanism to human AML

    PubMed Central

    Verbiest, Tom; Bouffler, Simon; Nutt, Stephen L.; Badie, Christophe

    2015-01-01

    The transcription factor PU.1, encoded by the murine Sfpi1 gene (SPI1 in humans), is a member of the Ets transcription factor family and plays a vital role in commitment and maturation of the myeloid and lymphoid lineages. Murine studies directly link primary acute myeloid leukaemia (AML) and decreased PU.1 expression in specifically modified strains. Similarly, a radiation-induced chromosome 2 deletion and subsequent Sfpi1 point mutation in the remaining allele lead to murine radiation-induced AML. Consistent with murine data, heterozygous deletion of the SPI1 locus and mutation of the −14kb SPI1 upstream regulatory element were described previously in human primary AML, although they are rare events. Other mechanisms linked to PU.1 downregulation in human AML include TP53 deletion, FLT3-ITD mutation and the recurrent AML1-ETO [t(8;21)] and PML-RARA [t(15;17)] translocations. This review provides an up-to-date overview on our current understanding of the involvement of PU.1 in the initiation and development of radiation-induced AML, together with recommendations for future murine and human studies. PMID:25750172

  17. N -Methyl- N -nitrosourea-induced Renal Tumors in Rats: Immunohistochemical Comparison to Human Wilms Tumors

    PubMed Central

    Yoshizawa, Katsuhiko; Kinoshita, Yuichi; Emoto, Yuko; Kimura, Ayako; Uehara, Norihisa; Yuri, Takashi; Shikata, Nobuaki; Tsubura, Airo

    2013-01-01

    N-Methyl-N-nitrosourea (MNU)-induced renal tumors in rats and Wilms tumors in humans were compared. Renal mesenchymal tumors (RMTs) and nephroblastomas (blastemal and epithelial components) in female Lewis rats treated with a single intraperitoneal injection of 50 mg/kg MNU at birth and Wilms tumors (blastemal, epithelial and mesenchymal components) in humans were analyzed for the expression of pancytokeratin (CK), vimentin, p63, α-smooth muscle actin (SMA), desmin, S-100, CD57, CD117/c-kit, Wilms tumor 1 protein (WT1) and β-catenin. The mesenchymal components of rat RMTs and human Wilms tumors expressed vimentin, SMA and β-catenin. The blastemal components of rat nephroblastomas and human Wilms tumors expressed vimentin, CD117/c-kit and β-catenin. The epithelial components of rat nephroblastomas and human Wilms tumors expressed vimentin and β-catenin. WT1 was expressed in different cellular components of rat tumors as compared with human Wilms tumors; the expression was seen in mesenchymal tumors and blastemal components of nephroblastomas in rats and epithelial components in human Wilms tumors. CK, p63 and CD57 were not expressed in rat RMTs or nephroblastomas, while CK and WT1 were expressed in epithelial components and CD57 was expressed in blastemal and epithelial components of human Wilms tumors. Rat and human tumors were universally negative for the expression of desmin and S-100. The immunohistochemical characteristics of rat renal tumors and human Wilms tumors may provide valuable information on the differences in renal oncogenesis and biology between the two species. PMID:23914056

  18. 6-Thioguanine-loaded polymeric micelles deplete myeloid-derived suppressor cells and enhance the efficacy of T cell immunotherapy in tumor-bearing mice

    SciTech Connect

    Jeanbart, Laura; Kourtis, Iraklis C.; van der Vlies, André J.; Swartz, Melody A.; Hubbell, Jeffrey A.

    2015-05-16

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells that suppress effector T cell responses and can reduce the efficacy of cancer immunotherapies. We previously showed that ultra-small polymer nanoparticles efficiently drain to the lymphatics after intradermal injection and target antigen-presenting cells, including Ly6chi Ly6gmonocytic MDSCs (Mo-MDSCs), in skin-draining lymph nodes (LNs) and spleen. Here, we developed ultra-small polymer micelles loaded with 6-thioguanine (MC-TG), a cytotoxic drug used in the treatment of myelogenous leukemia, with the aim of killing Mo-MDSCs in tumor-bearing mice and thus enhancing T cell-mediated anti-tumor responses. We found that 2 days post-injection in tumor-bearing mice (B16-F10 melanoma or E.G7-OVA thymoma), MC-TG depleted Mo-MDSCs in the spleen, Ly6clo Ly6g+ granulocytic MDSCs (G-MDSCs) in the draining LNs, and Gr1int Mo-MDSCs in the tumor. In both tumor models, MC-TG decreased the numbers of circulating Mo- and G-MDSCs, as well as of Ly6chi macrophages, for up to 7 days following a single administration. MDSC depletion was dose dependent and more effective with MC-TG than with equal doses of free TG. Finally, we tested whether this MDSC-depleting strategy might enhance cancer immunotherapies in the B16-F10 melanoma model. We found that MC-TG significantly improved the efficacy of adoptively transferred, OVA-specific CD8+ T cells in melanoma cells expressing OVA. Ultimately, these findings highlight the capacity of MC-TG in depleting MDSCs in the tumor microenvironment and show promise in promoting anti-tumor immunity when used in combination with T cell immunotherapies.

  19. PU.1 affects proliferation of the human acute myeloid leukemia U937 cell line by directly regulating MEIS1

    PubMed Central

    ZHOU, JING; ZHANG, XIAOFENG; WANG, YUHUA; GUAN, YINGHUI

    2015-01-01

    The transcription factor PU.1 is a member of the ETS family, which is expressed in a wide variety of hematopoietic lineages. Accumulating evidence has indicated that PU.1 plays a key role in hematopoiesis, and reduced expression of PU.1 leads to the pathogenesis of human myeloid leukemia. As a multi-functional factor, PU.1 is also required for mixed lineage leukemia (MLL) stem cell potential and the development of MLL. However, the function of PU.1 in human non-MLL leukemia and its molecular mechanism remains poorly understood. In the present study, PU.1 siRNA was demonstrated to efficiently inhibit the transcription level of oncogene MEIS1 in the human acute myeloid non-MLL leukemia U937 cell line. In addition, PU.1, as a positive regulator of MEIS1, performed a crucial role in maintaining cell proliferation. Using electrophoretic mobility shift assay, chromatin immunoprecipitation analysis and luciferase reporter assay, previously unexplored evidence that PU.1 activated the MEIS1 promoter through a conserved binding motif in vitro and in vivo was further defined. Overall, the present study provides insight into the molecular mechanism of the contribution of PU.1 to the pathogenesis of non-MLL U937 cells, which is mediated by direct regulation of MEIS1 transcription. The present data reveal the possibility of developing an alternative therapy for non-MLL leukemia by targeting PU.1-mediated MEIS1 gene activation. PMID:26622774

  20. SECTM1 Produced by Tumor Cells Attracts Human Monocytes Via CD7-mediated Activation of the PI3K Pathway

    PubMed Central

    Wang, Tao; Ge, Yingbin; Xiao, Min; Lopez-Coral, Alfonso; Li, Ling; Roesch, Alexander; Huang, Catherine; Alexander, Peter; Vogt, Thomas; Xu, Xiaowei; Hwang, Wei-Ting; Lieu, Melissa; Belser, Eric; Liu, Rui; Somasundaram, Rajasekharan; Herlyn, Meenhard; Kaufman, Russel E.

    2013-01-01

    Tumor-associated macrophages (TAMs) play essential roles in tumor progression and metastasis. Tumor cells recruit myeloid progenitors and monocytes to the tumor site, where they differentiate into TAMs; however, this process is not well studied in humans. Here we show that human CD7, a T cell and NK cell receptor, is highly expressed by monocytes and macrophages. Expression of CD7 decreases in M-CSF differentiated macrophages and in Melanoma-conditioned Medium Induced Macrophages (MCMI/Mϕ) in comparison to monocytes. A ligand for CD7, SECTM1 (Secreted and transmembrane protein 1), is highly expressed in many tumors, including melanoma cells. We show that SECTM1 binds to CD7 and significantly increases monocyte migration by activation of the PI3K pathway. In human melanoma tissues, tumor-infiltrating macrophages expressing CD7 are present. These melanomas, with CD7-positive inflammatory cell infiltrations, frequently highly express SECTM1, including an N-terminal, soluble form, which can be detected in the sera of metastatic melanoma patients but not in normal sera. Taken together, our data demonstrate that CD7 is present on monocytes and tumor macrophages, and that its ligand, SECTM1, is frequently expressed in corresponding melanoma tissues, possibly acting as a chemoattractant for monocytes to modulate the melanoma microenvironment. PMID:24157461

  1. Biological Analysis of Human CML Stem Cells; Xenograft Model of Chronic Phase Human Chronic Myeloid Leukemia.

    PubMed

    Abraham, Sheela A

    2016-01-01

    Xenograft mouse models have been instrumental in expanding our knowledge of hematopoiesis and can provide a functional description of stem cells that possess engrafting potential. Here we describe methodology outlining one way of analyzing human malignant cells that are able to engraft immune compromised mice. Using models such as these will allow researchers to gain valuable insight into the primitive leukemic subtypes that evade current therapy regimes and are critical to understand, in order to eradicate malignancy. PMID:27581148

  2. Dendritic Cells in the Context of Human Tumors: Biology and Experimental Tools.

    PubMed

    Volovitz, Ilan; Melzer, Susanne; Amar, Sarah; Bocsi, József; Bloch, Merav; Efroni, Sol; Ram, Zvi; Tárnok, Attila

    2016-03-01

    Dendritic cells (DC) are the most potent and versatile antigen-presenting cells (APC) in the immune system. DC have an exceptional ability to comprehend the immune context of a captured antigen based on molecular signals identified from its vicinity. The analyzed information is then conveyed to other immune effector cells. Such capability enables DC to play a pivotal role in mediating either an immunogenic response or immune tolerance towards an acquired antigen. This review summarizes current knowledge on DC in the context of human tumors. It covers the basics of human DC biology, elaborating on the different markers, morphology and function of the different subsets of human DC. Human blood-borne DC are comprised of at least three subsets consisting of one plasmacytoid DC (pDC) and two to three myeloid DC (mDC) subsets. Some tissues have unique DC. Each subset has a different phenotype and function and may induce pro-tumoral or anti-tumoral effects. The review also discusses two methods fundamental to the research of DC on the single-cell level: multicolor flow cytometry (FCM) and image-based cytometry (IC). These methods, along with new genomics and proteomics tools, can provide high-resolution information on specific DC subsets and on immune and tumor cells with which they interact. The different layers of collected biological data may then be integrated using Immune-Cytomics modeling approaches. Such novel integrated approaches may help unravel the complex network of cellular interactions that DC carry out within tumors, and may help harness this complex immunological information into the development of more effective treatments for cancer. PMID:27007190

  3. A zebrafish model of Poikiloderma with Neutropenia recapitulates the human syndrome hallmarks and traces back neutropenia to the myeloid progenitor

    PubMed Central

    Colombo, Elisa A.; Carra, Silvia; Fontana, Laura; Bresciani, Erica; Cotelli, Franco; Larizza, Lidia

    2015-01-01

    Poikiloderma with Neutropenia (PN) is an autosomal recessive genodermatosis characterized by early-onset poikiloderma, pachyonychia, hyperkeratosis, bone anomalies and neutropenia, predisposing to myelodysplasia. The causative C16orf57/USB1 gene encodes a conserved phosphodiesterase that regulates the stability of spliceosomal U6-RNA. The involvement of USB1 in splicing has not yet allowed to unveil the pathogenesis of PN and how the gene defects impact on skin and bone tissues besides than on the haematological compartment. We established a zebrafish model of PN using a morpholino-knockdown approach with two different splicing morpholinos. Both usb1-depleted embryos displayed developmental abnormalities recapitulating the signs of the human syndrome. Besides the pigmentation and osteochondral defects, usb1-knockdown caused defects in circulation, manifested by a reduced number of circulating cells. The overall morphant phenotype was also obtained by co-injecting sub-phenotypic dosages of the two morpholinos and could be rescued by human USB1 RNA. Integrated in situ and real-time expression analyses of stage-specific markers highlighted defects of primitive haematopoiesis and traced back the dramatic reduction in neutrophil myeloperoxidase to the myeloid progenitors showing down-regulated pu.1 expression. Our vertebrate model of PN demonstrates the intrinsic requirement of usb1 in haematopoiesis and highlights PN as a disorder of myeloid progenitors associated with bone marrow dysfunction. PMID:26522474

  4. Interplay between HIV-1 and Toll-like receptors in human myeloid cells: friend or foe in HIV-1 pathogenesis?

    PubMed

    Donninelli, Gloria; Gessani, Sandra; Del Cornò, Manuela

    2016-01-01

    The Toll-like receptors are the first line of the host response to pathogens, representing an essential component of the innate and adaptive immune response. They recognize different pathogens and trigger responses directed at eliminating the invader and at developing immunologic long-term memory, ultimately affecting viral pathogenesis. In viral infections, sensing of nucleic acids and/or viral structural proteins generally induces a protective immune response. Thus, it is not surprising that many viruses have developed strategies to evade or counteract signaling through the Toll-like receptor pathways, to survive the host defense machinery and ensure propagation. Thus, Toll-like receptor engagement can also be part of viral pathogenic mechanisms. Evidence for a direct interaction of Toll-like receptors with human immunodeficiency virus type 1 (HIV-1) structures has started to be achieved, and alterations of their expression and function have been described in HIV-1-positive subjects. Furthermore, Toll-like receptor triggering by bacterial and viral ligands have been described to modulate HIV-1 replication and host response, leading to protective or detrimental effects. This review covers major advances in the field of HIV-1 interplay with Toll-like receptors, focusing on human myeloid cells (e.g., monocytes/macrophages and dendritic cells). The role of this interaction in the dysregulation of myeloid cell function and in dictating aspects of the multifaceted pathogenesis of acquired immunodeficiency syndrome will be discussed. PMID:26307548

  5. FLT3 and CDK4/6 inhibitors: signaling mechanisms and tumor burden in subcutaneous and orthotopic mouse models of acute myeloid leukemia.

    PubMed

    Zhang, Yaping; Hsu, Cheng-Pang; Lu, Jian-Feng; Kuchimanchi, Mita; Sun, Yu-Nien; Ma, Ji; Xu, Guifen; Zhang, Yilong; Xu, Yang; Weidner, Margaret; Huard, Justin; D'Argenio, David Z

    2014-12-01

    FLT3(ITD) subtype acute myeloid leukemia (AML) has a poor prognosis with currently available therapies. A number of small molecule inhibitors of FLT3 and/or CDK4/6 are currently under development. A more complete and quantitative understanding of the mechanisms of action of FLT3 and CDK4/6 inhibitors may better inform the development of current and future compounds that act on one or both of the molecular targets, and thus may lead to improved treatments for AML. In this study, we investigated in both subcutaneous and orthotopic AML mouse models, the mechanisms of action of three FLT3 and/or CDK4/6 inhibitors: AMG925 (Amgen), sorafenib (Bayer and Onyx), and quizartinib (Ambit Biosciences). A composite model was developed to integrate the plasma pharmacokinetics of these three compounds on their respective molecular targets, the coupling between the target pathways, as well as the resulting effects on tumor burden reduction in the subcutaneous xenograft model. A sequential modeling approach was used, wherein model structures and estimated parameters from upstream processes (e.g. PK, cellular signaling) were fixed for modeling subsequent downstream processes (cellular signaling, tumor burden). Pooled data analysis was employed for the plasma PK and cellular signaling modeling, while population modeling was applied to the tumor burden modeling. The resulting model allows the decomposition of the relative contributions of FLT3(ITD) and CDK4/6 inhibition on downstream signaling and tumor burden. In addition, the action of AMG925 on cellular signaling and tumor burden was further studied in an orthotopic tumor mouse model more closely representing the physiologically relevant environment for AML. PMID:25326874

  6. ChIP-seq Analysis of Human Chronic Myeloid Leukemia Cells.

    PubMed

    Anders, Lars; Li, Zhaodong

    2016-01-01

    Many transcription factors, chromatin-associated proteins and regulatory DNA elements are genetically and/or epigenetically altered in cancer, including Chronic Myeloid Leukemia (CML). This leads to deregulation of transcription that is often causally linked to the tumorigenic state. Chromatin-immunoprecipitation coupled with massively parallel DNA sequencing (ChIP-seq) is the key technology to study transcription as it allows in vivo whole-genome mapping of epigenetic modifications and interactions of proteins with DNA or chromatin. However, numerous DNA/chromatin-binding proteins, including EZH2, remain difficult to "ChIP," thus yielding genome-wide binding maps of only suboptimal quality. Here, we describe a ChIP-seq protocol optimized for high-quality protein-genome binding maps that have proven especially useful for studying difficult to 'ChIP' transcription regulatory factors in Chronic Myeloid Leukemia (CML) and related malignancies. PMID:27581144

  7. Patient-Derived Tumor Xenografts Are Susceptible to Formation of Human Lymphocytic Tumors1

    PubMed Central

    Bondarenko, Gennadiy; Ugolkov, Andrey; Rohan, Stephen; Kulesza, Piotr; Dubrovskyi, Oleksii; Gursel, Demirkan; Mathews, Jeremy; O’Halloran, Thomas V.; Wei, Jian J.; Mazar, Andrew P.

    2015-01-01

    Patient-derived xenograft (PDX) tumor models have emerged as a new approach to evaluate the effects of cancer drugs on patients’ personalized tumor grafts enabling to select the best treatment for the cancer patient and providing a new tool for oncology drug developers. Here, we report that human tumors engrafted in immunodeficient mice are susceptible to formation of B-and T-cell PDX tumors. We xenografted human primary and metastatic tumor samples into immunodeficient mice and found that a fraction of PDX tumors generated from patients’ samples of breast, colon, pancreatic, bladder and renal cancer were histologically similar to lymphocytic neoplasms. Moreover, we found that the first passage of breast and pancreatic cancer PDX tumors after initial transplantation of the tumor pieces from the same human tumor graft could grow as a lymphocytic tumor in one mouse and as an adenocarcinoma in another mouse. Whereas subcutaneous PDX tumors resembling human adenocarcinoma histology were slow growing and non-metastatic, we found that subcutaneous PDX lymphocytic tumors were fast growing and formed large metastatic lesions in mouse lymph nodes, liver, lungs, and spleen. PDX lymphocytic tumors were comprised of B-cells which were Epstein-Barr virus positive and expressed CD45 and CD20. Because B-cells are typically present in malignant solid tumors, formation of B-cell tumor may evolve in a wide range of PDX tumor models. Although PDX tumor models show great promise in the development of personalized therapy for cancer patients, our results suggest that confidence in any given PDX tumor model requires careful screening of lymphocytic markers. PMID:26476081

  8. Myeloid suppressor cells in cancer: recruitment, phenotype, properties, and mechanisms of immune suppression.

    PubMed

    Serafini, Paolo; Borrello, Ivan; Bronte, Vincenzo

    2006-02-01

    Growing tumors acquire the ability to resist immune recognition and immune-mediated injury. Among several mechanisms, mouse and human tumors share the ability to alter the normal hematopoiesis, leading to accumulation of cells of the myelo-monoctytic lineage at the tumor site and in different primary and secondary lymphoid organs. These cells aid tumor development by providing molecules and factors essential for tumor growth and neovascularization but also exert a profound inhibitory activity on both tumor-specific and nonspecific T lymphocytes. The present article summarizes recent findings on the interaction between developing cancers and these recently described "myeloid suppressor cells". PMID:16168663

  9. Finasteride Enhances the Generation of Human Myeloid-Derived Suppressor Cells by Up-Regulating the COX2/PGE2 Pathway.

    PubMed

    Zhang, Shaoying; Wu, Kang; Liu, Yufeng; Lin, Yingtong; Zhang, Xu; Zhou, Jie; Zhang, Hui; Pan, Ting; Fu, Yongshui

    2016-01-01

    Myeloid-derived suppressor cells (MDSCs) have been known to be a key factor in the regulation of the immune system under numerous conditions such as tumors, infections, autoimmune diseases, and transplantations. In contrast to the proposed deleterious role of MDSCs in tumors and infections, MDSCs with their suppressive function are now proved to have the beneficial potential of suppressing the autoimmune response and promoting tolerance to transplantation. Therefore, the expansion of MDSCs could be a promising therapeutic strategy for many diseases. In this study, we aimed to identify FDA-approved drugs that could aid in the expansion of functional MDSCs. We performed a high-throughput screening (HTS) of FDA-approved drugs based on the in vitro human MDSC-differentiation system and identified finasteride (FIN) to have the best potency to aid the generation of human MDSCs. The FIN-induced MDSCs were quite similar to monocytic MDSCs with regard to their surface phenotype, morphology, immunosuppressive function, and related gene expression. Next, we aimed to determine the mechanism of action of FIN and found that FIN induced the expansion of MDSCs through up-regulation of the COX2/PGE2 pathway by enhancing the activity of COX2 promoter. In addition, the administration of indomethacin (IND), a COX2 inhibitor, abrogated the effect of FIN. Based on these results, we suggested that FIN could find applications in the future in the expansion of MDSCs. Further development of FIN-like compounds could be a novel strategy for generating functional MDSCs for immunosuppressive therapies in various immune disorder conditions. PMID:27253400

  10. Finasteride Enhances the Generation of Human Myeloid-Derived Suppressor Cells by Up-Regulating the COX2/PGE2 Pathway

    PubMed Central

    Liu, Yufeng; Lin, Yingtong; Zhang, Xu; Zhou, Jie; Zhang, Hui; Pan, Ting; Fu, Yongshui

    2016-01-01

    Myeloid-derived suppressor cells (MDSCs) have been known to be a key factor in the regulation of the immune system under numerous conditions such as tumors, infections, autoimmune diseases, and transplantations. In contrast to the proposed deleterious role of MDSCs in tumors and infections, MDSCs with their suppressive function are now proved to have the beneficial potential of suppressing the autoimmune response and promoting tolerance to transplantation. Therefore, the expansion of MDSCs could be a promising therapeutic strategy for many diseases. In this study, we aimed to identify FDA-approved drugs that could aid in the expansion of functional MDSCs. We performed a high-throughput screening (HTS) of FDA-approved drugs based on the in vitro human MDSC-differentiation system and identified finasteride (FIN) to have the best potency to aid the generation of human MDSCs. The FIN-induced MDSCs were quite similar to monocytic MDSCs with regard to their surface phenotype, morphology, immunosuppressive function, and related gene expression. Next, we aimed to determine the mechanism of action of FIN and found that FIN induced the expansion of MDSCs through up-regulation of the COX2/PGE2 pathway by enhancing the activity of COX2 promoter. In addition, the administration of indomethacin (IND), a COX2 inhibitor, abrogated the effect of FIN. Based on these results, we suggested that FIN could find applications in the future in the expansion of MDSCs. Further development of FIN-like compounds could be a novel strategy for generating functional MDSCs for immunosuppressive therapies in various immune disorder conditions. PMID:27253400

  11. Experimental chemotherapy of human tumors heterotransplanted in nude mice.

    PubMed

    Giovanella, B C

    1980-01-01

    Human tumors heterotransplanted in nude mice offer the most realistic model for experimental chemotherapy of human neoplasms. Almost all the known human malignancies have been successfully transplanted in the nudes, although the rate of takes varies considerably between different tumor types. So far, a good correlation has been observed between the results obtained treating with the same drug the same tumor in the patient and in the nude mouse. Our experience in this field is, however, still too limited for the direct extrapolation of chemotherapeutic results obtained in the nudes to human tumors. PMID:6998362

  12. Lung Epithelial Cell-Specific Expression of Human Lysosomal Acid Lipase Ameliorates Lung Inflammation and Tumor Metastasis in Lipa(-/-) Mice.

    PubMed

    Zhao, Ting; Ding, Xinchun; Du, Hong; Yan, Cong

    2016-08-01

    Lysosomal acid lipase (LAL), a key enzyme in the metabolic pathway of neutral lipids, has a close connection with inflammation and tumor progression. One major manifestation in LAL-deficient (Lipa(-/-)) mice is an increase of tumor growth and metastasis associated with expansion of myeloid-derived suppressor cells. In the lung, LAL is highly expressed in alveolar type II epithelial cells. To assess how LAL in lung epithelial cells plays a role in this inflammation-related pathogenic process, lung alveolar type II epithelial cell-specific expression of human LAL (hLAL) in Lipa(-/-) mice was established by crossbreeding of CCSP-driven rtTA transgene and (TetO)7-CMV-hLAL transgene into Lipa(-/-) mice (CCSP-Tg/KO). hLAL expression in lung epithelial cells not only reduced tumor-promoting myeloid-derived suppressor cells in the lung, but also down-regulated the synthesis and secretion of tumor-promoting cytokines and chemokines into the bronchoalveolar lavage fluid of Lipa(-/-) mice. hLAL expression reduced the immunosuppressive functions of bronchoalveolar lavage fluid cells, inhibited bone marrow cell transendothelial migration, and inhibited endothelial cell proliferation and migration in Lipa(-/-) mice. As a result, hLAL expression in CCSP-Tg/KO mice corrected pulmonary damage, and inhibited tumor cell proliferation and migration in vitro, and tumor metastasis to the lung in vivo. These results support a concept that LAL is a critical metabolic enzyme in lung epithelial cells that regulates lung homeostasis, immune response, and tumor metastasis. PMID:27461363

  13. CD33-specific chimeric antigen receptor T cells exhibit potent preclinical activity against human acute myeloid leukemia.

    PubMed

    Kenderian, S S; Ruella, M; Shestova, O; Klichinsky, M; Aikawa, V; Morrissette, J J D; Scholler, J; Song, D; Porter, D L; Carroll, M; June, C H; Gill, S

    2015-08-01

    Patients with chemo-refractory acute myeloid leukemia (AML) have a dismal prognosis. Chimeric antigen receptor T (CART) cell therapy has produced exciting results in CD19+ malignancies and may overcome many of the limitations of conventional leukemia therapies. We developed CART cells to target CD33 (CART33) using the anti-CD33 single chain variable fragment used in gemtuzumab ozogamicin (clone My96) and tested the activity and toxicity of these cells. CART33 exhibited significant effector functions in vitro and resulted in eradication of leukemia and prolonged survival in AML xenografts. CART33 also resulted in human lineage cytopenias and reduction of myeloid progenitors in xenograft models of hematopoietic toxicity, suggesting that permanently expressed CD33-specific CART cells would have unacceptable toxicity. To enhance the viability of CART33 as an option for AML, we designed a transiently expressed mRNA anti-CD33 CAR. Gene transfer was carried out by electroporation into T cells and resulted in high-level expression with potent but self-limited activity against AML. Thus our preclinical studies show potent activity of CART33 and indicate that transient expression of anti-CD33 CAR by RNA modification could be used in patients to avoid long-term myelosuppression. CART33 therapy could be used alone or as part of a preparative regimen prior to allogeneic transplantation in refractory AML. PMID:25721896

  14. Antitumor activity of ethanol extract from Hippophae rhamnoides L. leaves towards human acute myeloid leukemia cells in vitro.

    PubMed

    Zhamanbaeva, G T; Murzakhmetova, M K; Tuleukhanov, S T; Danilenko, M P

    2014-12-01

    We studied the effects of ethanol extract from Hippophae rhamnoides L. leaves on the growth and differentiation of human acute myeloid leukemia cells (KG-1a, HL60, and U937). The extract of Hippophae rhamnoides L. leaves inhibited cell growth depending on the cell strain and extract dose. In a high concentration (100 μg/ml), the extract also exhibited a cytotoxic effect on HL60 cells. Hippophae rhamnoides L. leaves extract did not affect cell differentiation and did not modify the differentiating effect of calcitriol, active vitamin D metabolite. Inhibition of cell proliferation was paralleled by paradoxical accumulation of phase S cells (synthetic phase) with a reciprocal decrease in the count of G1 cells (presynthetic phase). The extract in a concentration of 100 μg/ml induced the appearance of cells with a subdiploid DNA content (sub-G1 phase cells), which indicated induction of apoptosis. The antiproliferative effect of Hippophae rhamnoides L. extract on acute myeloid leukemia cells was at least partially determined by activation of the S phase checkpoint, which probably led to deceleration of the cell cycle and apoptosis induction. PMID:25432283

  15. Human tumor antigens identified with monoclonal antibodies

    SciTech Connect

    AlSedairy, S.T.

    1987-01-01

    MoAbLc1 (IgM) and MoAbLc2 (IgG/sub 2a/) were produced against human lung carcinoma cell line (ChaGo). Lc1 recognizes a approx. = 330-kd/approx. = 310-kd glycoprotein complexes, and Lc2 recognizes a approx. = 60-kd/approx. = 47-kd protein complex. With a panel of cell lines of different tissue origin, Lc1 showed a more restricted reactivity to ChaGo; it cross-reacted with another lung carcinoma cell line (SK-Lc-2) and two breast carcinoma cell lines, but failed to react with cell lines of fetal lung, of colon, esophageal, prostate, stomach, and ovarian carcinomas, of B and T lymphoblastoid cells, neuroblastomas, glioblastoma, astrocytoma, and human peripheral blood lymphocytes. New and improved methods were developed for the production of indium-111-labeled MoAbs for tumor imaging. To facilitate the application of bicyclic anhydride diethylenetriaminepentaacetic acid (BADTPA) to In-111 labeling of antibodies, we have modified the original method by using C-14-labeled BADTPA, which allows precise quantitation of DTPA molecules incorporated. A new heterobifunctional reagent, 2,6-dioxo-N-(carboxyl)morpholine (DCM) was synthesized for chelating In-111 to MoAbs, and demonstrated higher retention of immunoreactivity of the labeled antibody.

  16. Human and mouse chromosomal mapping of the myeloid cell leukemia-1 gene: MCL1 maps to human chromosome 1q21, a region that is frequently altered in preneoplastic and neoplastic disease

    SciTech Connect

    Craig, R.W.; Zhou, P.; Kozopas, K.M.

    1994-09-15

    The MCL1 gene, recently identified in a myeloid leukemia cell line, has sequence similarity to BCL2, the gene at the t(14;18) translocation in follicular lymphoma. The chromosomal location of MCL1 has now been determined. The human locus (MCL1) was mapped to the long arm of human chromosome 1q21, using the methods of in situ hybridization and somatic cell hybrid analysis. In the mouse, MCL1-related sequences were mapped to positions on two mouse chromosomes (chromosomes 3 and 5), using haplotype analysis of an interspecific cross. The location of the locus on mouse chromosome 3 (Mcl1) was homologous to that of MCL1 on human chromosome 1; the second locus (Mcl-rs on mouse chromosome 5) may represent a pseudogene. The proximal long arm of human chromosome 1, where MCL1 is located, is duplicated and/or rearranged in a variety of preneoplastic and neoplastic diseases including hematologic diseases and solid tumors. MCL1 is thus a candidate gene for involvement in cancer. 46 refs., 2 figs., 3 tabs.

  17. Tumor-associated GM-CSF overexpression induces immunoinhibitory molecules via STAT3 in myeloid-suppressor cells infiltrating liver metastases.

    PubMed

    Thorn, M; Guha, P; Cunetta, M; Espat, N J; Miller, G; Junghans, R P; Katz, S C

    2016-06-01

    Assumptions that liver immune cells and immunosuppressive pathways are similar to their counterparts in other spaces have led to gaps in our understanding of intrahepatic neoplasm aggressiveness. Myeloid-derived suppressor cells (MDSCs) are potent inhibitors of antitumor immunity and pose a major obstacle to solid tumor treatment. Liver MDSCs (L-MDSCs) associated with liver metastases (LM) are particularly problematic by contributing to intrahepatic immunosuppression that promotes tumor progression. L-MDSCs have been reported to expand in response to granulocyte-macrophages colony-stimulating factor (GM-CSF) and suppress antitumor immunity in LM. To extend these findings, we examined mechanisms of intrahepatic immunosuppression exploited by L-MDSCs. We found that the majority of L-MDSCs co-expressed GM-CSF receptor (GM-CSF-R), indoleamine 2,3-dioxygenase (IDO) and programmed death ligand 1 (PD-L1), while demonstrating high levels of signal transducer and activator of transcription factor 3 (STAT3) activation. GM-CSF-secreting tumor cells induced STAT3 phosphorylation in L-MDSCs in addition to expression of IDO and PD-L1. GM-CSF or GM-CSF-R blockade markedly reduced L-MDSC IDO and PD-L1 expression, implicating tumor-derived GM-CSF in supporting L-MDSC-immunoinhibitory molecule expression. Small-molecule inhibitors of Janus-activated kinase 2 (JAK2) and STAT3 also dramatically diminished IDO and PD-L1 expression in L-MDSCs. We determined that STAT3 exerts transcriptional control over L-MDSC IDO and PD-L1 expression by binding to the IDO1 and PD-L1 promoters. Our data suggest that the GM-CSF/JAK2/STAT3 axis in L-MDSCs drives immunosuppression in a model of LM and blockade of this pathway may enable rescue of intrahepatic antitumor immunity. PMID:27199222

  18. Does nutrition support stimulate tumor growth in humans?

    PubMed

    Bossola, Maurizio; Pacelli, Fabio; Rosa, Fausto; Tortorelli, Antonio; Doglietto, Giovan Battista

    2011-04-01

    Many studies have been conducted to ascertain if nutrition support (NS), either as parenteral nutrition (PN) or enteral nutrition (EN), stimulates tumor growth and causes cancer progression, but after almost 30 years, the question remains at least in part unresolved. In this study, previous studies were reviewed to evaluate the effect of NS on tumor growth, tumor proliferation, tumor apoptosis, and cancer-related survival in humans. MEDLINE and PubMed were searched using combinations of the following keywords: PN, EN, tumor growth, tumor proliferation, tumor apoptosis, arginine, ω-3 fatty acids, and glutamine. Unfortunately, the effect of nutrition support on tumor growth has been assessed only in terms of tumor proliferation, whereas the interferences on tumor apoptosis have never been determined. Overall, the results seem conflicting and inconclusive. Similarly, it remains unknown if PN or EN enriched with specific nutrients such as arginine, ω-3 fatty acids, and glutamine can affect tumor growth in humans. It is hoped that further studies will elucidate if NS with conventional or specific nutrients stimulates tumor proliferation, interferes with tumor apoptosis, and causes cancer progression. PMID:21447771

  19. Caffeine affects the biological responses of human hematopoietic cells of myeloid lineage via downregulation of the mTOR pathway and xanthine oxidase activity

    PubMed Central

    Abooali, Maryam; Yasinska, Inna M.; Casely-Hayford, Maxwell A.; Berger, Steffen M.; Fasler-Kan, Elizaveta; Sumbayev, Vadim V.

    2015-01-01

    Correction of human myeloid cell function is crucial for the prevention of inflammatory and allergic reactions as well as leukaemia progression. Caffeine, a naturally occurring food component, is known to display anti-inflammatory effects which have previously been ascribed largely to its inhibitory actions on phosphodiesterase. However, more recent studies suggest an additional role in affecting the activity of the mammalian target of rapamycin (mTOR), a master regulator of myeloid cell translational pathways, although detailed molecular events underlying its mode of action have not been elucidated. Here, we report the cellular uptake of caffeine, without metabolisation, by healthy and malignant hematopoietic myeloid cells including monocytes, basophils and primary acute myeloid leukaemia mononuclear blasts. Unmodified caffeine downregulated mTOR signalling, which affected glycolysis and the release of pro-inflammatory/pro-angiogenic cytokines as well as other inflammatory mediators. In monocytes, the effects of caffeine were potentiated by its ability to inhibit xanthine oxidase, an enzyme which plays a central role in human purine catabolism by generating uric acid. In basophils, caffeine also increased intracellular cyclic adenosine monophosphate (cAMP) levels which further enhanced its inhibitory action on mTOR. These results demonstrate an important mode of pharmacological action of caffeine with potentially wide-ranging therapeutic impact for treating non-infectious disorders of the human immune system, where it could be applied directly to inflammatory cells. PMID:26384306

  20. Caffeine affects the biological responses of human hematopoietic cells of myeloid lineage via downregulation of the mTOR pathway and xanthine oxidase activity.

    PubMed

    Gibbs, Bernhard F; Gonçalves Silva, Isabel; Prokhorov, Alexandr; Abooali, Maryam; Yasinska, Inna M; Casely-Hayford, Maxwell A; Berger, Steffen M; Fasler-Kan, Elizaveta; Sumbayev, Vadim V

    2015-10-01

    Correction of human myeloid cell function is crucial for the prevention of inflammatory and allergic reactions as well as leukaemia progression. Caffeine, a naturally occurring food component, is known to display anti-inflammatory effects which have previously been ascribed largely to its inhibitory actions on phosphodiesterase. However, more recent studies suggest an additional role in affecting the activity of the mammalian target of rapamycin (mTOR), a master regulator of myeloid cell translational pathways, although detailed molecular events underlying its mode of action have not been elucidated. Here, we report the cellular uptake of caffeine, without metabolisation, by healthy and malignant hematopoietic myeloid cells including monocytes, basophils and primary acute myeloid leukaemia mononuclear blasts. Unmodified caffeine downregulated mTOR signalling, which affected glycolysis and the release of pro-inflammatory/pro-angiogenic cytokines as well as other inflammatory mediators. In monocytes, the effects of caffeine were potentiated by its ability to inhibit xanthine oxidase, an enzyme which plays a central role in human purine catabolism by generating uric acid. In basophils, caffeine also increased intracellular cyclic adenosine monophosphate (cAMP) levels which further enhanced its inhibitory action on mTOR. These results demonstrate an important mode of pharmacological action of caffeine with potentially wide-ranging therapeutic impact for treating non-infectious disorders of the human immune system, where it could be applied directly to inflammatory cells. PMID:26384306

  1. Swift Intrahepatic Accumulation of Granulocytic Myeloid-Derived Suppressor Cells in a Humanized Mouse Model of Toxic Shock Syndrome.

    PubMed

    Szabo, Peter A; Goswami, Ankur; Memarnejadian, Arash; Mallett, Christiane L; Foster, Paula J; McCormick, John K; Haeryfar, S M Mansour

    2016-06-15

    Toxic shock syndrome (TSS) and other superantigen-mediated illnesses are associated with 'systemic' immunosuppression that jeopardizes the host's ability to fight pathogens. Here, we define a novel mechanism of 'local' immunosuppression that may benefit the host. Systemic exposure to staphylococcal enterotoxin B (SEB) rapidly and selectively recruited CD11b(+)Gr-1(high)Ly-6C(+) granulocytic myeloid-derived suppressor cells (MDSCs) to the liver of HLA-DR4 transgenic mice. Hepatic MDSCs inhibited SEB-triggered T cell proliferation in a reactive oxygen species-dependent manner, and ex vivo-generated human MDSCs also similarly attenuated the proliferative response of autologous T cells to SEB. We propose a role for MDSCs in mitigating excessive tissue injury during TSS. PMID:26908735

  2. UBASH3B/Sts-1-CBL axis regulates myeloid proliferation in human preleukemia induced by AML1-ETO

    PubMed Central

    Goyama, Susumu; Schibler, Janet; Gasilina, Anjelika; Shrestha, Mahesh; Lin, Shan; Link, Kevin A.; Chen, Jianjun; Whitman, Susan P.; Bloomfield, Clara D.; Nicolet, Deedra; Assi, Salam; Ptasinska, Anetta; Heidenreich, Olaf; Bonifer, Constanze; Kitamura, Toshio; Nassar, Nicolas N.; Mulloy, James C.

    2015-01-01

    The t(8;21) rearrangement, which creates the AML1-ETO fusion protein, represents the most common chromosomal translocation in acute myeloid leukemia (AML). Clinical data suggest that CBL mutations are a frequent event in t(8;21) AML, but the role of CBL in AML1-ETO-induced leukemia has not been investigated. In this study, we demonstrate that CBL mutations collaborate with AML1-ETO to expand human CD34+ cells both in vitro and in a xenograft model. CBL depletion by shRNA also promotes the growth of AML1-ETO cells, demonstrating the inhibitory function of endogenous CBL in t(8;21) AML. Mechanistically, loss of CBL function confers hyper-responsiveness to thrombopoietin and enhances STAT5/AKT/ERK/Src signaling in AML1-ETO cells. Interestingly, we found the protein tyrosine phosphatase UBASH3B/Sts-1, which is known to inhibit CBL function, is upregulated by AML1-ETO through transcriptional and miR-9-mediated regulation. UBASH3B/Sts-1 depletion induces an aberrant pattern of CBL phosphorylation and impairs proliferation in AML1-ETO cells. The growth-inhibition caused by UBASH3B/Sts-1 depletion can be rescued by ectopic expression of CBL mutants, suggesting that UBASH3B/Sts-1 supports the growth of AML1-ETO cells partly through modulation of CBL function. Our study reveals a role of CBL in restricting myeloid proliferation of human AML1-ETO-induced leukemia, and identifies UBASH3B/Sts-1 as a potential target for pharmaceutical intervention. PMID:26449661

  3. Establishment and Characterization of a Human Neuroendocrine Tumor Xenograft.

    PubMed

    Yang, Zhaoying; Zhang, Le; Serra, Stefano; Law, Calvin; Wei, Alice; Stockley, Tracy L; Ezzat, Shereen; Asa, Sylvia L

    2016-06-01

    Neuroendocrine tumors (NETs) are increasing in incidence yet the cause of these tumors remains unknown. Familial associations have shed light on the genetic basis of some of these tumors, but sporadic tumors seem to have primarily epigenetic dysregulation. The rarity of cell lines and animal models has been a barrier to studies of treatment modalities. We set out to develop a xenograft model of gastrointestinal NETs. Primary human NETs were collected at the time of surgery under sterile conditions and xenografted into the flanks of immunodeficient mice. Tumor growth was measured and when tumors reached 1500 mm(3), they were excised and half was re-xenografted through multiple generations. The other half was bisected; a part was frozen and a part was fixed for morphologic and immunohistochemical characterization as well as molecular validation of fidelity of a successful xenograft. Of 106 human NETs, seven were successfully engrafted of which only one tumor was successfully propagated for eight passages. Two years later, the tumor retains its neuroendocrine features and similarity to the original primary human tumor. It has retained expression of keratin as well as chromogranin A reactivity. The establishment of a NET xenograft provides a model for further study of the biological behavior of these tumors and can be used to examine the in vivo effects of various medical and targeted radiotherapeutic agents on tumor growth. PMID:27067082

  4. Characterization of miRNomes in Acute and Chronic Myeloid Leukemia Cell Lines

    PubMed Central

    Xiong, Qian; Yang, Yadong; Wang, Hai; Li, Jie; Wang, Shaobin; Li, Yanming; Yang, Yaran; Cai, Kan; Ruan, Xiuyan; Yan, Jiangwei; Hu, Songnian; Fang, Xiangdong

    2014-01-01

    Myeloid leukemias are highly diverse diseases and have been shown to be associated with microRNA (miRNA) expression aberrations. The present study involved an in-depth miRNome analysis of two human acute myeloid leukemia (AML) cell lines, HL-60 and THP-1, and one human chronic myeloid leukemia (CML) cell line, K562, via massively parallel signature sequencing. mRNA expression profiles of these cell lines that were established previously in our lab facilitated an integrative analysis of miRNA and mRNA expression patterns. miRNA expression profiling followed by differential expression analysis and target prediction suggested numerous miRNA signatures in AML and CML cell lines. Some miRNAs may act as either tumor suppressors or oncomiRs in AML and CML by targeting key genes in AML and CML pathways. Expression patterns of cell type-specific miRNAs could partially reflect the characteristics of K562, HL-60 and THP-1 cell lines, such as actin filament-based processes, responsiveness to stimulus and phagocytic activity. miRNAs may also regulate myeloid differentiation, since they usually suppress differentiation regulators. Our study provides a resource to further investigate the employment of miRNAs in human leukemia subtyping, leukemogenesis and myeloid development. In addition, the distinctive miRNA signatures may be potential candidates for the clinical diagnosis, prognosis and treatment of myeloid leukemias. PMID:24755403

  5. Induced Differentiation of Human Myeloid Leukemia Cells into M2 Macrophages by Combined Treatment with Retinoic Acid and 1α,25-Dihydroxyvitamin D3

    PubMed Central

    Takahashi, Hiromichi; Hatta, Yoshihiro; Iriyama, Noriyoshi; Hasegawa, Yuichiro; Uchida, Hikaru; Nakagawa, Masaru; Makishima, Makoto; Takeuchi, Jin; Takei, Masami

    2014-01-01

    Retinoids and 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) induce differentiation of myeloid leukemia cells into granulocyte and macrophage lineages, respectively. All-trans retinoic acid (ATRA), which is effective in the treatment of acute promyelocytic leukemia, can induce differentiation of other types of myeloid leukemia cells, and combined treatment with retinoid and 1,25(OH)2D3 effectively enhances the differentiation of leukemia cells into macrophage-like cells. Recent work has classified macrophages into M1 and M2 types. In this study, we investigated the effect of combined treatment with retinoid and 1,25(OH)2D3 on differentiation of myeloid leukemia THP-1 and HL60 cells. 9-cis Retinoic acid (9cRA) plus 1,25(OH)2D3 inhibited proliferation of THP-1 and HL60 cells and increased myeloid differentiation markers including nitroblue tetrazolium reducing activity and expression of CD14 and CD11b. ATRA and the synthetic retinoic acid receptor agonist Am80 exhibited similar effects in combination with 1,25(OH)2D3 but less effectively than 9cRA, while the retinoid X receptor agonist HX630 was not effective. 9cRA plus 1,25(OH)2D3 effectively increased expression of M2 macrophage marker genes, such as CD163, ARG1 and IL10, increased surface CD163 expression, and induced interleukin-10 secretion in myeloid leukemia cells, while 9cRA alone had weaker effects on these phenotypes and 1,25(OH)2D3 was not effective. Taken together, our results demonstrate selective induction of M2 macrophage markers in human myeloid leukemia cells by combined treatment with 9cRA and 1,25(OH)2D3. PMID:25409436

  6. Tfe3 expression is closely associated to macrophage terminal differentiation of human hematopoietic myeloid precursors

    SciTech Connect

    Zanocco-Marani, Tommaso; Vignudelli, Tatiana; Gemelli, Claudia; Pirondi, Sara; Testa, Anna; Montanari, Monica; Parenti, Sandra; Tenedini, Elena; Grande, Alexis; Ferrari, Sergio . E-mail: sergio@unimo.it

    2006-12-10

    The MItf-Tfe family of basic helix-loop-helix leucine zipper (bHLH-Zip) transcription factors encodes four family members: MItf, Tfe3, TfeB and TfeC. In vitro, each protein of the family binds DNA in a homo- or heterodimeric form with other family members. Tfe3 is involved in chromosomal translocations recurrent in different tumors and it has been demonstrated, by in vivo studies, that it plays, redundantly with MItf, an important role in the process of osteoclast formation, in particular during the transition from mono-nucleated to multi-nucleated osteoclasts. Since mono-nucleated osteoclasts derive from macrophages we investigated whether Tfe3 might play a role upstream during hematopoietic differentiation. Here we show that Tfe3 is able to induce mono-macrophagic differentiation of U937 cells, in association with a decrease of cell proliferation and an increase of apoptosis. We also show that Tfe3 does not act physiologically during commitment of CD34+ hematopoietic stem cells (HSCs), since it is not able to direct HSCs toward a specific lineage as observed by clonogenic assay, but is a strong actor of terminal differentiation since it allows human primary myeloblasts' maturation toward the macrophage lineage.

  7. The immune receptor Tim-3 acts as a trafficker in a Tim-3/galectin-9 autocrine loop in human myeloid leukemia cells

    PubMed Central

    Gonçalves Silva, Isabel; Rüegg, Laura; Gibbs, Bernhard F.; Bardelli, Marco; Fruehwirth, Alexander; Varani, Luca; Berger, Steffen M.; Fasler-Kan, Elizaveta; Sumbayev, Vadim V.

    2016-01-01

    ABSTRACT The immune receptor Tim-3 is often highly expressed in human acute myeloid leukemia (AML) cells where it acts as a growth factor and inflammatory receptor. Recently, it has been demonstrated that Tim-3 forms an autocrine loop with its natural ligand galectin-9 in human AML cells. However, the pathophysiological functions of Tim-3 in human AML cells remain unclear. Here, we report for the first time that Tim-3 is required for galectin-9 secretion in human AML cells. However, this effect is cell-type specific and was found so far to be applicable only to myeloid (and not, for example, lymphoid) leukemia cells. We concluded that AML cells might use Tim-3 as a trafficker for the secretion of galectin-9 which can then be possibly used to impair the anticancer activities of cytotoxic T cells and natural killer (NK) cells. PMID:27622049

  8. The immune receptor Tim-3 acts as a trafficker in a Tim-3/galectin-9 autocrine loop in human myeloid leukemia cells.

    PubMed

    Gonçalves Silva, Isabel; Rüegg, Laura; Gibbs, Bernhard F; Bardelli, Marco; Fruehwirth, Alexander; Varani, Luca; Berger, Steffen M; Fasler-Kan, Elizaveta; Sumbayev, Vadim V

    2016-07-01

    The immune receptor Tim-3 is often highly expressed in human acute myeloid leukemia (AML) cells where it acts as a growth factor and inflammatory receptor. Recently, it has been demonstrated that Tim-3 forms an autocrine loop with its natural ligand galectin-9 in human AML cells. However, the pathophysiological functions of Tim-3 in human AML cells remain unclear. Here, we report for the first time that Tim-3 is required for galectin-9 secretion in human AML cells. However, this effect is cell-type specific and was found so far to be applicable only to myeloid (and not, for example, lymphoid) leukemia cells. We concluded that AML cells might use Tim-3 as a trafficker for the secretion of galectin-9 which can then be possibly used to impair the anticancer activities of cytotoxic T cells and natural killer (NK) cells. PMID:27622049

  9. Immune checkpoint inhibitors enhance cytotoxicity of cytokine-induced killer cells against human myeloid leukaemic blasts.

    PubMed

    Poh, Su Li; Linn, Yeh Ching

    2016-05-01

    We studied whether blockade of inhibitory receptors on cytokine-induced killer (CIK) cells by immune checkpoint inhibitors could increase its anti-tumour potency against haematological malignancies. CIK cultures were generated from seven normal donors and nine patients with acute myeloid leukaemia (AML), acute lymphoblastic leukaemia (ALL) or multiple myeloma (MM). The inhibitory receptors B and T lymphocyte attenuator, CD200 receptor, lymphocyte activation gene-3 (LAG-3) and T cell immunoglobulin and mucin-domain-containing-3 (TIM-3) were present at variable percentages in most CIK cultures, while cytotoxic T lymphocyte-associated protein 4 (CTLA-4), programmed death-1 (PD-1) and killer cell immunoglobulin-like receptors (KIR2DL1/2/3) were expressed at low level in most cultures. Without blockade, myeloid leukaemia cells were susceptible to autologous and allogeneic CIK-mediated cytotoxicity. Blockade of KIR, LAG-3, PD-1 and TIM-3 but not CTLA-4 resulted in remarkable increase in killing against these targets, even in those with poor baseline cytotoxicity. ALL and MM targets were resistant to CIK-mediated cytotoxicity, and blockade of receptors did not increase cytotoxicity to a meaningful extent. Combination of inhibitors against two receptors did not further increase cytotoxicity. Interestingly, potentiation of CIK killing by blocking antibodies was not predicted by expression of receptors on CIK and their respective ligands on the targets. Compared to un-activated T and NK cells, blockade potentiated the cytotoxicity of CIK cells to a greater degree and at a lower E:T ratio, but without significant increase in cytotoxicity against normal white cell. Our findings provide the basis for clinical trial combining autologous CIK cells with checkpoint inhibitors for patients with AML. PMID:26961084

  10. Impaired responses of leukemic dendritic cells derived from a human myeloid cell line to LPS stimulation.

    PubMed

    Kim, Kwang Dong; Choi, Seung-Chul; Noh, Young-Woock; Kim, Jong Wan; Paik, Sang-Gi; Yang, Young; Kim, Keun; Lim, Jong-Seok

    2006-02-28

    Several myeloid leukemia-derived cells have been reported to possess the ability to differentiate into dendritic cells (DC). MUTZ-3, a myeloid leukemia cell line, responds to GM-CSF, IL-4 and TNF-alpha, and acquires a phenotype similar to immature monocyte-derived DC (MoDC). In the present study, MUTZ-3-derived DC (MuDC) showed high level expression of HLA class II molecules, CD80 and CD86, and were able to function as potent antigen presenting cells as previously reported. Interestingly, MuDC maturation was induced by CD40- mediated stimulation, but not by LPS stimulation. We analyzed CCR1, CCR7 and Toll-like receptor (TLR) expressions in MuDC, and measured IL-10 and IL-12 production after maturation stimuli. Although MuDC expressed the mRNA for TLR4, a major component of the LPS receptor system, they did not show an enhanced level of CCR7 or cytokine production after LPS stimulation. In contrast, they responded to CD40 stimulation, which resulted in increased levels of CD83, CD86 and CCR7. Moreover, while LPS- stimulated MoDC could potently stimulate NK cells in a DC-NK cell co-culture, LPS-stimulated MuDC failed to stimulate primary NK cells. Taken together, our findings suggest that, although MuDC express TLR4, unlike TNF-alpha and IL-1beta, LPS does not stimulate MuDC to acquire mature phenotypes, and they may have impaired activity to initiate innate immune response. PMID:16520555

  11. DNA demethylating agent 5-azacytidine inhibits myeloid-derived suppressor cells induced by tumor growth and cyclophosphamide treatment.

    PubMed

    Mikysková, Romana; Indrová, Marie; Vlková, Veronika; Bieblová, Jana; Símová, Jana; Paracková, Zuzana; Pajtasz-Piasecka, Elzbieta; Rossowska, Joanna; Reinis, Milan

    2014-01-01

    MDSCs represent one of the key players mediating immunosuppression. These cells accumulate in the TME, lymphoid organs, and blood during tumor growth. Their mobilization was also reported after CY therapy. DNMTi 5AC has been intensively studied as an antitumor agent. In this study, we examined, using two different murine tumor models, the modulatory effects of 5AC on TU-MDSCs and CY-MDSCs tumor growth and CY therapy. Indeed, the percentage of MDSCs in the TME and spleens of 5AC-treated mice bearing TRAMP-C2 or TC-1/A9 tumors was found decreased. The changes in the MDSC percentage were accompanied by a decrease in the Arg-1 gene expression, both in the TME and spleens. CY treatment of the tumors resulted in additional MDSC accumulation in the TME and spleens. This accumulation was subsequently inhibited by 5AC treatment. A combination of CY with 5AC led to the highest tumor growth inhibition. Furthermore, in vitro cultivation of spleen MDSCs in the presence of 5AC reduced the percentage of MDSCs. This reduction was associated with an increased percentage of CD11c(+) and CD86(+)/MHCII(+) cells. The observed modulatory effect on MDSCs correlated with a reduction of the Arg-1 gene expression, VEGF production, and loss of suppressive capacity. Similar, albeit weaker effects were observed when MDSCs from the spleens of tumor-bearing animals were cultivated with 5AC. Our findings indicate that beside the direct antitumor effect, 5AC can reduce the percentage of MDSCs accumulating in the TME and spleens during tumor growth and CY chemotherapy, which can be beneficial for the outcome of cancer therapy. PMID:24389335

  12. Comparative Epigenomics of Human and Mouse Mammary Tumors

    PubMed Central

    Demircan, Berna; Dyer, Lisa M.; Gerace, Mallory; Lobenhofer, Edward K.; Robertson, Keith D.; Brown, Kevin D.

    2010-01-01

    Gene silencing by aberrant epigenetic chromatin alteration is a well-recognized event contributing to tumorigenesis. While genetically engineered tumor-prone mouse models have proven a powerful tool in understanding many aspects of carcinogenesis, to date few studies have focused on epigenetic alterations in mouse tumors. To uncover epigenetically silenced tumor suppressor genes (TSGs) in mouse mammary tumor cells, we conducted initial genome-wide screening by combining the treatment of cultured cells with the DNA demethylating drug 5-aza-2′-deoxycytidine (5-azadC) and the histone deacetylase inhibitor trichostatin A (TSA) with expression microarray. By conducting this initial screen on EMT6 cells and applying protein function and genomic structure criteria to genes identified as upregulated in response to 5-azadC/TSA, we were able to identify 2 characterized breast cancer TSGs (Timp3 and Rprm) and 4 putative TSGs (Atp1B2, Dusp2, FoxJ1 and Smpd3) silenced in this line. By testing a panel of ten mouse mammary tumor lines, we determined that each of these genes is commonly hypermethylated, albeit with varying frequency. Furthermore, by examining a panel of human breast tumor lines and primary tumors we observed that the human orthologs of ATP1B2, FOXJ1 and SMPD3 are aberrantly hypermethylated in the human disease while DUSP2 was not hypermethylated in primary breast tumors. Finally, we examined hypermethylation of several genes targeted for epigenetic silencing in human breast tumors in our panel of ten mouse mammary tumor lines. We observed that the orthologs of Cdh1, RarB, Gstp1, RassF1 genes were hypermethylated, while neither Dapk1 nor Wif1 were aberrantly methylated in this panel of mouse tumor lines. From this study, we conclude that there is significant, but not absolute, overlap in the epigenome of human and mouse mammary tumors. PMID:18836996

  13. Anesthetic agent propofol inhibits myeloid differentiation factor 88-dependent and independent signaling and mitigates lipopolysaccharide-mediated reactive oxygen species production in human neutrophils in vitro.

    PubMed

    Ren, Xuli; Lv, Fei; Fang, Bo; Liu, Song; Lv, Huangwei; He, Guannan; Ma, Hong; Cao, Yaming; Wang, Yue

    2014-12-01

    Engagement of toll-like receptor 4 (TLR4) can activate the myeloid differentiation factor 88 (MyD88)/toll-interleukin-1-resistance domain-containing adapter-inducing interferon-β (TRIF) dependent pathways, inducing production of reactive oxygen species (ROS) in neutrophils. Propofol (PPF) has both anti-oxidant and anti-inflammatory properties. However, the molecular mechanism by which PPF influences human neutrophil function is yet to be elucidated. This study aimed to investigate the influence of PPF on lipopolysaccharide (LPS)-induced reactive oxygen species production in human neutrophils. We isolated neutrophils from the peripheral blood of 10 healthy male donors. Neither 1 µg/ml LPS nor 10-150 μmol/L PPF influenced the rate of neutrophil apoptosis, but PPF significantly inhibited LPS-mediated reactive oxygen species production in a dose-dependent manner. PPF inhibited LPS-induced expression of MyD88, tumor necrosis factor receptor-associated factor 6, and TRIF, but not the expression of interferon regulatory factor 3 or phosphorylation of p47(phox), p38-mitogen-activated protein kinase, and nuclear factor (NF)-κB, particularly in the neutrophils in which MyD88 or TRIF had been silenced by siRNA. The inhibitory effect of PPF on LPS-induced activation of p47(phox), p38-mitogen-activated protein kinase, and NF-κB was partially antagonized by over-expression of MyD88 or TRIF in neutrophils. These observations provide insights into the mechanisms responsible for the anti-inflammatory properties of PPF. PPF reduces LPS-induced production of reactive oxygen species in neutrophils via inhibiting expression of MyD88 and TRIF signaling. PMID:25446563

  14. Wilms Tumor 1 rs16754 predicts favorable clinical outcomes for acute myeloid leukemia patients in South Chinese population.

    PubMed

    Zhang, Dao-Yu; Yan, Han; Cao, Shan; Zhang, Wei; Li, Xiao-Lin; Zeng, Hui; Chen, Xiao-Ping

    2015-06-01

    The single nucleotide polymorphism (SNP) rs16754 in WT1 shows a clinical implication in Caucasus population. However, the results were not reproducible in different population cohorts. We evaluated the clinical significance of rs16754 for 205 de novo acute myeloid leukemia (AML) patients in South Chinese population, 188 healthy volunteers were recruited as healthy controls. WT1 mRNA expression was investigated in 81 pretreatment bone marrow specimens. WT1(GA/AA) patients showed better overall survival (OS, P=0.006) and relapse-free survival (RFS, P=0.025) as compared with WT1(GG) patients, and the favorable clinical outcomes were most prominent in older patients with superior OS (P=0.001) and RFS (P=0.003). In multivariable analysis, rs16754 was still associated with favorable OS (HR=1.533, P=0.042). The WT1(GG) patients showed significantly higher WT1 mRNA expression than the WT1(GA/AA) patients (P=0.01). In summary, WT1 rs16754 may serve as an independent biomarker in AML patients from South Chinese. PMID:25841655

  15. Establishment and characterization of five new human renal tumor xenografts.

    PubMed Central

    Beniers, A. J.; Peelen, W. P.; Schaafsma, H. E.; Beck, J. L.; Ramaekers, F. C.; Debruyne, F. M.; Schalken, J. A.

    1992-01-01

    Ten different human renal cell carcinoma (RCC) primary tumors were xenografted into BALB/c nu/nu mice. Five of the tumors (NU-10, NU-12, NU-20, NU-22, and NU-28) gave rise to serially transplantable tumors that were further characterized. Histology, DNA index, immunohistochemical characteristics, growth rate, and clonogenic potential were followed from primary tumor to the 5th to 15th transplant passage. Only one of the tumors (NU-20) showed remarkable instability for all tested parameters in the first five transplant passages. Histology of the other tumors was essentially the same to the histology of the primary tumors, although differences between human and host-derived vessels were apparent. DNA index values in general showed a trend toward an aneuploid character of the xenografts. Immunohistochemical analyses showed a loss of intensity of staining but a concomitant rise in the fraction of positively staining cells with antibodies against cytokeratins, vimentin, tumor-associated antigens, and human leukocyte antigen (HLA) class I antigens. Human leukocyte antigen class II antigen expression showed a loss of intensity as well as a decrease in the fraction of positive cells. Tumor doubling time was lowest in transplant passage number 0, and stable growth was noticed in transplant passages 1 through 4. Clonogenic potential of four of the lines was higher for the xenografts than for the primary tumors. The authors conclude that, on xenografting, histologic characteristics of the primary tumor are essentially conserved. Progression in the first transplant passages, however, results in tumors with a more aggressive character. Images Figure 1 PMID:1739137

  16. Antibodies targeting human IL1RAP (IL1R3) show therapeutic effects in xenograft models of acute myeloid leukemia

    PubMed Central

    Ågerstam, Helena; Karlsson, Christine; Hansen, Nils; Sandén, Carl; Askmyr, Maria; von Palffy, Sofia; Högberg, Carl; Rissler, Marianne; Wunderlich, Mark; Juliusson, Gunnar; Richter, Johan; Sjöström, Kjell; Bhatia, Ravi; Mulloy, James C.; Järås, Marcus; Fioretos, Thoas

    2015-01-01

    Acute myeloid leukemia (AML) is associated with a poor survival rate, and there is an urgent need for novel and more efficient therapies, ideally targeting AML stem cells that are essential for maintaining the disease. The interleukin 1 receptor accessory protein (IL1RAP; IL1R3) is expressed on candidate leukemic stem cells in the majority of AML patients, but not on normal hematopoietic stem cells. We show here that monoclonal antibodies targeting IL1RAP have strong antileukemic effects in xenograft models of human AML. We demonstrate that effector-cell–mediated killing is essential for the observed therapeutic effects and that natural killer cells constitute a critical human effector cell type. Because IL-1 signaling is important for the growth of AML cells, we generated an IL1RAP-targeting antibody capable of blocking IL-1 signaling and show that this antibody suppresses the proliferation of primary human AML cells. Hence, IL1RAP can be efficiently targeted with an anti-IL1RAP antibody capable of both achieving antibody-dependent cellular cytotoxicity and blocking of IL-1 signaling as modes of action. Collectively, these results provide important evidence in support of IL1RAP as a target for antibody-based treatment of AML. PMID:26261316

  17. Heterogeneity of Clonal Expansion and Maturation-Linked Mutation Acquisition in Hematopoietic Progenitors in Human Acute Myeloid Leukemia

    PubMed Central

    Walter, Roland B.; Laszlo, George S.; Lionberger, Jack M.; Pollard, Jessica A.; Harrington, Kimberly H.; Gudgeon, Chelsea J.; Othus, Megan; Rafii, Shahin; Meshinchi, Soheil; Appelbaum, Frederick R.; Bernstein, Irwin D.

    2014-01-01

    Recent technological advances led to an appreciation of the genetic complexity of human acute myeloid leukemia (AML) but underlying progenitor cells remain poorly understood because their rarity precludes direct study. We developed a co-culture method integrating hypoxia, aryl hydrocarbon receptor inhibition, and micro-environmental support via human endothelial cells to isolate these cells. X-chromosome inactivation studies of the least mature precursors derived following prolonged culture of CD34+/CD33− cells revealed polyclonal growth in highly curable AMLs, suggesting mutations necessary for clonal expansion were acquired in more mature progenitors. Consistently, in core-binding factor (CBF) leukemias with known complementing mutations, immature precursors derived following prolonged culture of CD34+/CD33− cells harbored neither mutation or the CBF mutation alone, whereas more mature precursors often carried both mutations. These results were in contrast to those with leukemias with poor prognosis that showed clonal dominance in the least mature precursors. These data indicate heterogeneity among progenitors in human AML that may have prognostic and therapeutic implications. PMID:24721792

  18. DNA methylation profiles in the human genes for tumor necrosis factors alpha and beta in subpopulations of leukocytes and in leukemias.

    PubMed Central

    Kochanek, S; Radbruch, A; Tesch, H; Renz, D; Doerfler, W

    1991-01-01

    The genomic sequencing technique has been applied to assess the state of methylation in the DNA from human leukocyte subpopulations from healthy individuals and in the DNA from several individuals with myeloid or lymphatic leukemias or non-Hodgkin lymphomas. Leukocyte populations were purified by the high-gradient magnetic cell sorting technique. In the human tumor necrosis factor alpha (TNF-alpha) gene segment between nucleotides 300 and 1150, the specific methylation profile in the DNA from human granulocytes and monocytes is maintained in three cases of myeloid leukemia. In one such case, all 5-methyl-2'-deoxycytidine residues have been replaced by cytidine. In a chronic lymphatic T-cell leukemia, all 5-methyl-2'-deoxycytidine residues have been substituted by cytidine. In normal B lymphocytes, in two cases of chronic lymphatic B-cell leukemias and two cases of non-Hodgkin lymphomas, all 5'-CG-3' sequences in this gene segment are devoid of methylation. In the TNF-beta gene, DNA methylation is decreased in several examples of acute or chronic myeloid leukemias in comparison to normal human granulocytes or monocytes, whose DNA is almost completely methylated between nucleotides 700 and 900. In human T and B lymphocytes, the main producers of TNF-beta, in three instances of chronic lymphatic leukemias and two cases of non-Hodgkin lymphomas, all 5'-CG-3' sequences are unmethylated in this region. The DNA from the human HeLa cell line is highly methylated at all 5'-CG-3' sequences in the TNF-alpha and -beta genes. The TNF-alpha gene is transcribed in the cells of one case of acute myeloid leukemia in which the analyzed region of the TNF-alpha gene is completely unmethylated. The TNF-beta gene is not transcribed in any of the malignant cells tested. Images PMID:2062856

  19. Detection of Human Polyomavirus 7 in human thymic epithelial tumors

    PubMed Central

    Rennspiess, Dorit; Pujari, Sreedhar; Keijzers, Marlies; Abdul-Hamid, Myrurgia A.; Hochstenbag, Monique; Dingemans, Anne-Marie; Kurz, Anna Kordelia; Speel, Ernst-Jan; Haugg, Anke; Pastrana, Diana V.; Buck, Christopher B.; De Baets, Marc H.; zur Hausen, Axel

    2014-01-01

    Introduction Although the molecular genetics possibly underlying the pathogenesis of human thymoma have been extensively studied, its etiology remains poorly understood. Since murine polyomavirus consistently induces thymomas in mice, we assessed the presence of the novel human polyomavirus 7 (HPyV7) in human thymic epithelial tumors. Methods HPyV7-DNA Fluorescence in situ hybridization (FISH), DNA-PCR and immuno-histochemistry (IHC) were performed in 37 thymomas. Of these, 26 were previously diagnosed with myasthenia gravis (MG). In addition, 20 thymic hyperplasias and 20 fetal thymic tissues were tested. Results HPyV7-FISH revealed specific nuclear hybridization signals within the neoplastic epithelial cells of 23 thymomas (62.2%). With some exceptions, the HPyV7-FISH data correlated with the HPyV7-DNA PCR. By IHC large T antigen (LTAg) expression of HPyV7 was detected, and double staining confirmed its expression in the neoplastic epithelial cells. Eighteen of the 26 MG-positive and 7 of the 11 MG-negative thymomas were HPyV7-positive. 40% of the 20 hyperplastic thymi were HPyV7-positive by PCR as confirmed by FISH and IHC in the follicular lymphocytes. All 20 fetal thymi tested HPyV7-negative. Conclusions The presence of HPyV7-DNA and LTAg expression in the majority of thymomas possibly link HPyV7 to human thymomagenesis. Further investigations are needed to elucidate the possible associations of HPyV7 and MG. PMID:25526237

  20. 5-Azacytidine treatment sensitizes tumor cells to T-cell mediated cytotoxicity and modulates NK cells in patients with myeloid malignancies.

    PubMed

    Gang, A O; Frøsig, T M; Brimnes, M K; Lyngaa, R; Treppendahl, M B; Grønbæk, K; Dufva, I H; Straten, P Thor; Hadrup, S R

    2014-01-01

    Treatment with the demethylating agent 5-Azacytidine leads to prolonged survival for patients with myelodysplastic syndrome, and the demethylation induces upregulation of cancer-testis antigens. Cancer-testis antigens are well-known targets for immune recognition in cancer, and the immune system may have a role in this treatment regimen. We show here that 5-Azacytidine treatment leads to increased T-cell recognition of tumor cells. T-cell responses against a large panel of cancer-testis antigens were detected before treatment, and these responses were further induced upon initiation of treatment. These characteristics point to an ideal combination of 5-Azacytidine and immune therapy to preferentially boost T-cell responses against cancer-testis antigens. To initiate such combination therapy, essential knowledge is required about the general immune modulatory effect of 5-Azacytidine. We therefore examined potential treatment effects on both immune stimulatory (CD8 and CD4 T cells and Natural Killer (NK) cells) and immune inhibitory cell subsets (myeloid-derived suppressor cells and regulatory T cells). We observed a minor decrease and modulation of NK cells, but for all other populations no effects could be detected. Together, these data support a strategy for combining 5-Azacytidine treatment with immune therapy for potential clinical benefit. PMID:24681961

  1. 5-Azacytidine treatment sensitizes tumor cells to T-cell mediated cytotoxicity and modulates NK cells in patients with myeloid malignancies

    PubMed Central

    Gang, A O; Frøsig, T M; Brimnes, M K; Lyngaa, R; Treppendahl, M B; Grønbæk, K; Dufva, I H; Straten, P thor; Hadrup, S R

    2014-01-01

    Treatment with the demethylating agent 5-Azacytidine leads to prolonged survival for patients with myelodysplastic syndrome, and the demethylation induces upregulation of cancer-testis antigens. Cancer-testis antigens are well-known targets for immune recognition in cancer, and the immune system may have a role in this treatment regimen. We show here that 5-Azacytidine treatment leads to increased T-cell recognition of tumor cells. T-cell responses against a large panel of cancer-testis antigens were detected before treatment, and these responses were further induced upon initiation of treatment. These characteristics point to an ideal combination of 5-Azacytidine and immune therapy to preferentially boost T-cell responses against cancer-testis antigens. To initiate such combination therapy, essential knowledge is required about the general immune modulatory effect of 5-Azacytidine. We therefore examined potential treatment effects on both immune stimulatory (CD8 and CD4 T cells and Natural Killer (NK) cells) and immune inhibitory cell subsets (myeloid-derived suppressor cells and regulatory T cells). We observed a minor decrease and modulation of NK cells, but for all other populations no effects could be detected. Together, these data support a strategy for combining 5-Azacytidine treatment with immune therapy for potential clinical benefit. PMID:24681961

  2. CD8 T-cell responses to Wilms tumor gene product WT1 and proteinase 3 in patients with acute myeloid leukemia.

    PubMed

    Scheibenbogen, Carmen; Letsch, Anne; Thiel, Eckhard; Schmittel, Alexander; Mailaender, Volker; Baerwolf, Steffi; Nagorsen, Dirk; Keilholz, Ulrich

    2002-09-15

    Wilms tumor gene product WT1 and proteinase 3 are overexpressed antigens in acute myeloid leukemia (AML), against which cytotoxic T lymphocytes can be elicited in vitro and in murine models. We performed this study to investigate whether WT1- and proteinase 3-specific CD8 T cells spontaneously occur in AML patients. T cells recognizing HLA-A2.1-binding epitopes from WT1 or proteinase 3 could be detected ex vivo in 5 of 15 HLA-A2-positive AML patients by interferon-gamma (IFN-gamma) ELISPOT assay and flow cytometry for intracellular IFN-gamma and in 3 additional patients by flow cytometry only. T cells producing IFN-gamma in response to proteinase 3 were further characterized in one patient by 4-color flow cytometry, identifying them as CD3(+)CD8(+)CD45RA(+) CCR7(-) T cells, resembling cytotoxic effector T cells. In line with this phenotype, most of the WT1- and proteinase-reactive T cells were granzyme B(+). These results provide for the first time evidence for spontaneous T-cell reactivity against defined antigens in AML patients. These data therefore support the immunogenicity of WT1 and proteinase 3 in acute leukemia patients and the potential usefulness of these antigens for leukemia vaccines. PMID:12200377

  3. Immunotherapy for acute myeloid leukemia.

    PubMed

    Jurcic, Joseph G

    2005-09-01

    Immunotherapeutic strategies have become part of standard cancer treatment. Chimeric and humanized antibodies have demonstrated activity against a variety of tumors. Although the humanized anti-CD33 antibody HuM195 has only modest activity against overt acute myeloid leukemia (AML), it can eliminate minimal residual disease in acute promyelocytic leukemia. High-dose radioimmunotherapy with b-particle-emitting isotopes targeting CD33, CD45, and CD66 can potentially allow intensification of antileukemic therapy before hematopoietic stem cell transplantation. Conversely, a-particle immunotherapy with isotopes such as bismuth-213 or actinium-225 offers the possibility of selective tumor cell kill while sparing surrounding normal tissues. Targeted chemotherapy with the anti-CD33- calicheamicin construct gemtuzumab ozogamicin has produced remissions in relapsed AML and appears promising when used in combination with standard chemotherapy for newly diagnosed AML. T-cell recognition of peptide antigens presented on the cell surface in combination with major histocompatibility complex antigen provides another potentially promising approach for the treatment of AML. PMID:16091194

  4. Myeloid cells as target of fingolimod action in multiple sclerosis

    PubMed Central

    Di Dario, Marco; Colombo, Emanuela; Govi, Chiara; De Feo, Donatella; Messina, Maria José; Romeo, Marzia; Sangalli, Francesca; Moiola, Lucia; Rodegher, Mariaemma; Martino, Gianvito; Martinelli, Vittorio; Comi, Giancarlo

    2015-01-01

    Objective: To track the effects of fingolimod, an approved drug for multiple sclerosis (MS), on the activation of myeloid cells from the periphery to the CNS. Methods: In vitro and ex vivo immunologic studies coupled with flow cytometry were performed to evaluate the action of fingolimod on lipopolysaccharide (LPS)–induced expression of activation markers in human monocytes from healthy participants, participants with untreated MS, and participants with fingolimod-treated MS. In vivo administration of fingolimod during experimental autoimmune encephalomyelitis (EAE) was established to verify the activation state of splenic, CNS infiltrating, and CNS resident myeloid cells ex vivo at flow cytometer. Results: We found that in vitro exposure of human monocytes to fingolimod inhibited LPS-induced CD25 and CD150 expression and tumor necrosis factor–α (TNF-α) secretion without altering immune cell survival. Further, EAE treatment with fingolimod led to reduced amounts of TNF-α produced by myeloid cells in vivo in the spleen and CNS. Finally, while displaying normal induction of CD25 and CD150 levels at high LPS concentration, monocytes from patients with fingolimod-treated MS showed significantly higher activation threshold at suboptimal LPS stimulation than controls. Conclusions: The inhibition of myeloid cell activation may be part of the immunosuppressive action of fingolimod and take place in the periphery and in the CNS. PMID:26587553

  5. Liver myeloid-derived suppressor cells expand in response to liver metastases in mice and inhibit the anti-tumor efficacy of anti-CEA CAR-T

    PubMed Central

    Burga, Rachel A.; Thorn, Mitchell; Point, Gary R.; Guha, Prajna; Nguyen, Cang T.; Licata, Lauren A.; DeMatteo, Ronald P.; Ayala, Alfred; Espat, N. Joseph; Junghans, Richard P.; Katz, Steven C.

    2015-01-01

    Chimeric antigen receptor modified T cell (CAR-T) technology, a promising immunotherapeutic tool, has not been applied specifically to treat liver metastases (LM). While CAR-T delivery to LM can be optimized by regional intrahepatic infusion, we propose that liver CD11b+Gr-1+ myeloid-derived suppressor cells (L-MDSC) will inhibit the efficacy of CAR-T in the intrahepatic space. We studied anti-CEA CAR-T in a murine model of CEA+ LM and identified mechanisms through which L-MDSC expand and inhibit CAR-T function. We established CEA+ LM in mice and studied purified L-MDSC and responses to treatment with intrahepatic anti-CEA CAR-T infusions. L-MDSC expanded three-fold in response to LM and their expansion was dependent on GM-CSF, which was produced by tumor cells. L-MDSC utilized PD-L1 to suppress anti-tumor responses through engagement of PD-1 on CAR-T. GM-CSF, in cooperation with STAT3, promoted L-MDSC PD-L1 expression. CAR-T efficacy was rescued when mice received CAR-T in combination with MDSC depletion, GM-CSF neutralization to prevent MDSC expansion, or PD-L1 blockade. As L-MDSC suppressed anti-CEA CAR-T, infusion of anti-CEA CAR-T in tandem with agents targeting L-MDSC is a rational strategy for future clinical trials. PMID:25850344

  6. Human umbilical cord blood myeloid progenitor cells are relatively chemoresistant: a potential model for autologous transplantations in HIV-infected newborns.

    PubMed

    Toren, A; Einat, M; Fabian, I; Nagler, A

    1997-11-01

    Vertical transmission from mother to child occurs in 15-39% of women infected with the human immunodeficiency virus (HIV). Stem cell transplantation has recently been suggested as a potential therapy for patients with HIV infection. We have examined the possible advantages of human cord blood (HUCB) stem cells over bone marrow (BM) stem cells in the treatment of HIV-infected newborns. HUCB myeloid progenitors were found to be statistically more resistant to interferon-alpha (IFN-alpha), cytarabine (ARA-C), and eilatin than BM myeloid progenitor cells grown with IL-3 (P < 0.05). HUCB treated with IFN-alpha, ARA-C, and eilatin demonstrated a significantly higher capacity for self-renewal manifested by delta assay following 7 days in liquid culture. We, therefore, suggest that HUCB purged by anti-HIV drugs may be a source for autologous transplantation in HIV-infected newborns. PMID:9371528

  7. A rapid culture technique produces functional dendritic-like cells from human acute myeloid leukemia cell lines.

    PubMed

    Ning, Jian; Morgan, David; Pamphilon, Derwood

    2011-01-01

    Most anti-cancer immunotherapeutic strategies involving dendritic cells (DC) as vaccines rely upon the adoptive transfer of DC loaded with exogenous tumour-peptides. This study utilized human acute myeloid leukemia (AML) cells as progenitors from which functional dendritic-like antigen presenting cells (DLC) were generated, that constitutively express tumour antigens for recognition by CD8(+) T cells. DLC were generated from AML cell lines KG-1 and MUTZ-3 using rapid culture techniques and appropriate cytokines. DLC were evaluated for their cell-surface phenotype, antigen uptake and ability to stimulate allogeneic responder cell proliferation, and production of IFN-γ; compared with DC derived from normal human PBMC donors. KG-1 and MUTZ-3 DLC increased expression of CD80, CD83, CD86, and HLA-DR, and MUTZ-3 DLC downregulated CD14 and expressed CD1a. Importantly, both KG-1 and MUTZ-3-derived DLC promoted proliferation of allogeneic responder cells more efficiently than unmodified cells; neither cells incorporated FITC-labeled dextran, but both stimulated IFN-γ production from responding allogeneic CD8(+) T cells. Control DC produced from PBMC using the FastDC culture also expressed high levels of critical cell surface ligands and demonstrated good APC function. This paper indicates that functional DLC can be cultured from the AML cell lines KG-1 and MUTZ-3, and FastDC culture generates functional KG-1 DLC. PMID:22187520

  8. A Rapid Culture Technique Produces Functional Dendritic-Like Cells from Human Acute Myeloid Leukemia Cell Lines

    PubMed Central

    Ning, Jian; Morgan, David; Pamphilon, Derwood

    2011-01-01

    Most anti-cancer immunotherapeutic strategies involving dendritic cells (DC) as vaccines rely upon the adoptive transfer of DC loaded with exogenous tumour-peptides. This study utilized human acute myeloid leukemia (AML) cells as progenitors from which functional dendritic-like antigen presenting cells (DLC) were generated, that constitutively express tumour antigens for recognition by CD8+ T cells. DLC were generated from AML cell lines KG-1 and MUTZ-3 using rapid culture techniques and appropriate cytokines. DLC were evaluated for their cell-surface phenotype, antigen uptake and ability to stimulate allogeneic responder cell proliferation, and production of IFN-γ; compared with DC derived from normal human PBMC donors. KG-1 and MUTZ-3 DLC increased expression of CD80, CD83, CD86, and HLA-DR, and MUTZ-3 DLC downregulated CD14 and expressed CD1a. Importantly, both KG-1 and MUTZ-3-derived DLC promoted proliferation of allogeneic responder cells more efficiently than unmodified cells; neither cells incorporated FITC-labeled dextran, but both stimulated IFN-γ production from responding allogeneic CD8+ T cells. Control DC produced from PBMC using the FastDC culture also expressed high levels of critical cell surface ligands and demonstrated good APC function. This paper indicates that functional DLC can be cultured from the AML cell lines KG-1 and MUTZ-3, and FastDC culture generates functional KG-1 DLC. PMID:22187520

  9. Cloning and expression of two human genes encoding calcium-binding proteins that are regulated during myeloid differentiation.

    PubMed Central

    Lagasse, E; Clerc, R G

    1988-01-01

    The cellular mechanisms involved in chronic inflammatory processes are poorly understood. This is especially true for the role of macrophages, which figure prominently in the inflammatory response. Two proteins, MRP8 and MRP14, which are expressed in infiltrate macrophages during inflammatory reactions but not in normal tissue macrophages, have been characterized. Here we report that MRP8 and MRP14 mRNAs are specifically expressed in human cells of myeloid origin and that their expression is regulated during monocyte-macrophage and granulocyte differentiation. To initiate the analysis of cis-acting elements governing the tissue-specific expression of the MRP genes, we cloned the human genes encoding MRP8 and MRP14. Both genes contain three exons, are single copy, and have a strikingly similar organization. They belong to a novel subfamily of highly homologous calcium-binding proteins which includes S100 alpha, S100 beta, intestinal calcium-binding protein, P11, and calcyclin (2A9). A transient expression assay was devised to investigate the tissue-specific regulatory elements responsible for MRP gene expression after differentiation in leukemia HL60 cells. The results of this investigation demonstrated that the cis-acting elements responsible for MRP expression are present on the cloned DNA fragment containing the MRP gene loci. Images PMID:3405210

  10. Protection of human myeloid dendritic cell subsets against influenza A virus infection is differentially regulated upon TLR stimulation.

    PubMed

    Baharom, Faezzah; Thomas, Saskia; Bieder, Andrea; Hellmér, Maria; Volz, Julia; Sandgren, Kerrie J; McInerney, Gerald M; Karlsson Hedestam, Gunilla B; Mellman, Ira; Smed-Sörensen, Anna

    2015-05-01

    The proinflammatory microenvironment in the respiratory airway induces maturation of both resident and infiltrating dendritic cells (DCs) upon influenza A virus (IAV) infection. This results in upregulation of antiviral pathways as well as modulation of endocytic processes, which affect the susceptibility of DCs to IAV infection. Therefore, it is highly relevant to understand how IAV interacts with and infects mature DCs. To investigate how different subsets of human myeloid DCs (MDCs) involved in tissue inflammation are affected by inflammatory stimulation during IAV infection, we stimulated primary blood MDCs and inflammatory monocyte-derived DCs (MDDCs) with TLR ligands, resulting in maturation. Interestingly, MDDCs but not MDCs were protected against IAV infection after LPS (TLR4) stimulation. In contrast, stimulation with TLR7/8 ligand protected MDCs but not MDDCs from IAV infection. The reduced susceptibility to IAV infection correlated with induction of type I IFNs. We found that differential expression of TLR4, TRIF, and MyD88 in the two MDC subsets regulated the ability of the cells to enter an antiviral state upon maturation. This difference was functionally confirmed using small interfering RNA and inhibitors. Our data show that different human MDC subsets may play distinct roles during IAV infection, as their capacity to induce type I IFNs is dependent on TLR-specific maturation, resulting in differential susceptibility to IAV infection. PMID:25801434

  11. GSK3β Inhibition Promotes Efficient Myeloid and Lymphoid Hematopoiesis from Non-human Primate-Induced Pluripotent Stem Cells

    PubMed Central

    D'Souza, Saritha S.; Maufort, John; Kumar, Akhilesh; Zhang, Jiuchun; Smuga-Otto, Kimberley; Thomson, James A.; Slukvin, Igor I.

    2016-01-01

    Summary Advances in the scalable production of blood cells from induced pluripotent stem cells (iPSCs) open prospects for the clinical translation of de novo generated blood products, and evoke the need for preclinical evaluation of their efficacy, safety, and immunogenicity in large animal models. Due to substantial similarities with humans, the outcomes of cellular therapies in non-human primate (NHP) models can be readily extrapolated to a clinical setting. However, the use of this model is hampered by relatively low efficiency of blood generation and lack of lymphoid potential in NHP-iPSC differentiation cultures. Here, we generated transgene-free iPSCs from different NHP species and showed the efficient induction of mesoderm, myeloid, and lymphoid cells from these iPSCs using a GSK3β inhibitor. Overall, our studies enable scalable production of hematopoietic progenitors from NHP-iPSCs, and lay the foundation for preclinical testing of iPSC-based therapies for blood and immune system diseases in an NHP model. PMID:26805448

  12. Isolation of Mouse and Human Tumor-Associated Macrophages

    PubMed Central

    Cassetta, Luca; Noy, Roy; Swierczak, Agnieszka; Sugano, Gaël; Smith, Harriet; Wiechmann, Lisa; Pollard, Jeffrey W.

    2016-01-01

    The tumor microenvironment is a complex network of cells that support tumor progression and malignancy. It has been demonstrated that tumor cells can educate the immune system to promote a tumor-friendly environment. Among all these immune cells, tumor-associated macrophages (TAMs) are well represented and their presence in mouse models has been shown to promote tumor progression and metastasis. These effects are through the stimulation of angiogenesis, enhancement of tumor cell invasion and intravasation, immunosuppression, and at the metastatic site tumor cell extravasation and growth. However, the precise mechanisms are not fully understood. Furthermore there is limited information on TAMs derived from human cancers. For this reason it is important to be able to extract TAMs from tumors in order to compare their phenotypes, functions, and transcriptomes with normal resident tissue macrophages. Isolation of these cells is challenging due to the lack of markers and standardized protocols. Here we show an optimized protocol for the efficient isolation and extraction of resident macrophages and TAMs from human and mouse tissues by using multicolor flow cytometry. These protocols allow for the extraction of thousands of macrophages in less than 5 h from tissues as small as half a gram. The isolated macrophages can then be used for both “omics” and in vitro studies. PMID:27325269

  13. Isolation of Mouse and Human Tumor-Associated Macrophages.

    PubMed

    Cassetta, Luca; Noy, Roy; Swierczak, Agnieszka; Sugano, Gaël; Smith, Harriet; Wiechmann, Lisa; Pollard, Jeffrey W

    2016-01-01

    The tumor microenvironment is a complex network of cells that support tumor progression and malignancy. It has been demonstrated that tumor cells can educate the immune system to promote a tumor-friendly environment. Among all these immune cells, tumor-associated macrophages (TAMs) are well represented and their presence in mouse models has been shown to promote tumor progression and metastasis. These effects are through the stimulation of angiogenesis, enhancement of tumor cell invasion and intravasation, immunosuppression, and at the metastatic site tumor cell extravasation and growth. However, the precise mechanisms are not fully understood. Furthermore there is limited information on TAMs derived from human cancers. For this reason it is important to be able to extract TAMs from tumors in order to compare their phenotypes, functions, and transcriptomes with normal resident tissue macrophages. Isolation of these cells is challenging due to the lack of markers and standardized protocols. Here we show an optimized protocol for the efficient isolation and extraction of resident macrophages and TAMs from human and mouse tissues by using multicolor flow cytometry. These protocols allow for the extraction of thousands of macrophages in less than 5 h from tissues as small as half a gram. The isolated macrophages can then be used for both "omics" and in vitro studies. PMID:27325269

  14. Regulation of human immunodeficiency virus type 1 and cytokine gene expression in myeloid cells by NF-kappa B/Rel transcription factors.

    PubMed Central

    Roulston, A; Lin, R; Beauparlant, P; Wainberg, M A; Hiscott, J

    1995-01-01

    CD4+ macrophages in tissues such as lung, skin, and lymph nodes, promyelocytic cells in bone marrow, and peripheral blood monocytes serve as important targets and reservoirs for human immunodeficiency virus type 1 (HIV-1) replication. HIV-1-infected myeloid cells are often diminished in their ability to participate in chemotaxis, phagocytosis, and intracellular killing. HIV-1 infection of myeloid cells can lead to the expression of surface receptors associated with cellular activation and/or differentiation that increase the responsiveness of these cells to cytokines secreted by neighboring cells as well as to bacteria or other pathogens. Enhancement of HIV-1 replication is related in part to increased DNA-binding activity of cellular transcription factors such as NF-kappa B. NF-kappa B binds to the HIV-1 enhancer region of the long terminal repeat and contributes to the inducibility of HIV-1 gene expression in response to multiple activating agents. Phosphorylation and degradation of the cytoplasmic inhibitor I kappa B alpha are crucial regulatory events in the activation of NF-kappa B DNA-binding activity. Both N- and C-terminal residues of I kappa B alpha are required for inducer-mediated degradation. Chronic HIV-1 infection of myeloid cells leads to constitutive NF-kappa B DNA-binding activity and provides an intranuclear environment capable of perpetuating HIV-1 replication. Increased intracellular stores of latent NF-kappa B may also result in rapid inducibility of NF-kappa B-dependent cytokine gene expression. In response to secondary pathogenic infections or antigenic challenge, cytokine gene expression is rapidly induced, enhanced, and sustained over prolonged periods in HIV-1-infected myeloid cells compared with uninfected cells. Elevated levels of several inflammatory cytokines have been detected in the sera of HIV-1-infected individuals. Secretion of myeloid cell-derived cytokines may both increase virus production and contribute to AIDS

  15. Modeling Breast Tumor Development with a Humanized Mouse Model.

    PubMed

    Arendt, Lisa M

    2016-01-01

    The tumor microenvironment plays a critical role in breast cancer growth and progression to metastasis. Here, we describe a method to examine stromal-epithelial interactions during tumor formation and progression utilizing human-derived mammary epithelial cells and breast stromal cells. This method outlines the isolation of each cell type from reduction mammoplasty tissue, the culture and genetic modification of both epithelial and stromal cells using lentiviral technology, and the method of humanizing and implantation of transformed epithelial cells into the cleared mammary fat pads of immunocompromised mice. This model system may be a useful tool to dissect signaling interactions that contribute to invasive tumor behavior and therapeutic resistance. PMID:27581027

  16. X-ray sensitivity of human tumor cells in vitro

    SciTech Connect

    Weichselbaum, R.R.; Nove, J.; Little, J.B.

    1980-04-01

    Clonally-derived cells from ten human malignant tumors considered radiocurable (breast, neuroblastoma, medulloblastoma) or non-radiocurable (osteosarcoma, hypernephroma, glioblastoma, melanoma) were studied in cell culture and their in vitro x-ray survival curve parameters determined (anti n, D/sub 0/). There were no significant differences among the tumor cell lines suggesting that survival parameters in vitro do not explain differences in clinical radiocurability. Preliminary investigation with density inhibited human tumor cells indicate that such an approach may yield information regarding inherent cellular differences in radiocurability.

  17. TGF{beta}-mediated formation of pRb-E2F complexes in human myeloid leukemia cells

    SciTech Connect

    Hu Xiaotang

    2008-05-02

    TGF{beta} is well known for its inhibitory effect on cell cycle G1 checkpoint kinases. However, its role in the control of pRb-E2F complexes is not well established. TGF{beta} inhibits phosphorylation of pRb at several serine and threonine residues and regulates the association of E2F transcription factors with pRb family proteins. Recent studies found that predominantly E2F-4, p130, and histone deacetylase (HDAC) are found to bind to corresponding E2F-responsive promoters in G0/G1 phase. As cells progress through mid-G1, p130-E2F4 complex are replaced by p107-E2F4 followed by activators E2F1, 2, and 3. pRb was not detectable in the promoters containing the E2F-responsive site in cycling cells but was associated with E2F4-p130 complexes or E2F4-p107 complexes during G0/G1 phase. In human myeloid leukemia cell line, MV4-11, TGF{beta} upregulated pRb-E2F-4 and p130-E2F-4, and downregulated p107-E2F-4 complexes. However, pRB-E2F1 and pRb-E2F3 complexes were found in proliferating cells but not in TGF{beta} arrested G1 cells. In addition, electrophoretic gel mobility shift assay (EMSA) could not detect pRb-E2F DNA-binding activities either in S or G1 phase but exhibited the existence of p107-E2F4 in proliferating cells and p130-E2F4 complexes in TGF{beta}-arrested G1 cells, respectively. Our data suggest that p107 and p130, but not pRb, and the repressor E2F, but not activator E2Fs, play a critical role in regulating E2F-responsive gene expression in TGF{beta}-mediated cell cycle control in human myeloid leukemia cells.

  18. Recent advances in managing human papillomavirus-positive oropharyngeal tumors

    PubMed Central

    Riccio, Stefano; Colombo, Sarah; Pompilio, Madia; Formillo, Paolo

    2010-01-01

    Human papillomavirus (HPV) is detected in a subset of patients with head and neck squamous cell carcinoma, most frequently in tumors in the Waldeyer's ring (palatine tonsil and base of tongue). Several studies suggest that patients with HPV-positive tumors have better survival with either concurrent chemoradiation therapy or surgery followed by radiation compared with HPV-negative patients. However, some possible confounding clinicopathologic variables may challenge the validity of this statement, for example, some authors used the TNM (tumor, node, metastasis) grouping stage while others used the primary tumor (T stage), and other studies have demonstrated that tumors with advanced T stage were less likely to be infected with HPV. A large clinical trial with stratification of patients according to all known tumor prognostic factors is crucial to solve the question. PMID:20948869

  19. Triptolide induces apoptotic cell death of human cholangiocarcinoma cells through inhibition of myeloid cell leukemia-1

    PubMed Central

    2014-01-01

    Background Cholangiocarcinoma (CCA), a devastating neoplasm, is highly resistant to current chemotherapies. CCA cells frequently overexpress the antiapoptotic protein myeloid cell leukemia-1(Mcl-1), which is responsible for its extraordinary ability to evade cell death. Triptolide, a bioactive ingredient extracted from Chinese medicinal plant, has been shown to inhibit cell proliferation and induce apoptosis in several cancers. Methods CCK-8 assay was performed to detect cell survival rate in vitro. DAPI staining and Flow cytometry were used to analyze apoptosis. Western blot was performed to determine the expression levels of caspase-3, caspase-7, caspase-9, PARP, and Mcl-1. Quantitative real-time PCR and immunofluorescence were used to detect the expression levels of Mcl-1. The nude mice xenograft model was used to evaluate the antitumor effect of triptolide in vivo. Results Triptolide reduced cell viability in cholangiocarcinoma cell lines in a dose- and time-dependent manner, with IC50 values of 12.6 ± 0.6 nM, 20.5 ± 4.2 nM, and 18.5 ± 0.7 nM at 48 h for HuCCT1, QBC939, and FRH0201 respectively. Triptolide induced apoptosis in CCA cell lines in part through mitochondrial pathway. Using quantitative real-time PCR, western blot and immunofluorescence, we have shown that triptolide downregulates Mcl-1 mRNA and protein levels. Furthermore, triptolide inhibited the CCA growth in vivo. Conclusions Triptolide has profound antitumor effect on CCA, probably by inducing apoptosis through inhibition of Mcl-1. Triptolide would be a promising therapeutic agent for CCA. PMID:24742042

  20. Heterogenous effects of bryostatin on human myeloid leukemia clonogenicity: dose and time scheduling dependency.

    PubMed

    van der Hem, K G; Schuurhuis, G J; Dräger, A M; Odding, J H; Huijgens, P C

    1996-09-01

    The potent anti-neoplastic actions displayed in vitro by bryostatins have led to the introduction of short-term bryostatin-1 infusions in phase I clinical trials. Because bryostatin (bryo) undergoes a rapid clearance in vivo, we were interested in its scheduling effects on acute myeloid leukemia (AML) clonogenicity. Therefore, we assessed the primary plating efficiency (PE1) of AML samples in response to several bryo concentrations after various preincubation periods in a semi-solid colony forming assay. Whereas continuous exposure to 10 nM bryo during the assay period reduced the PE1 in nearly all samples tested, preincubation of eight AML patients' specimens for 1, 2, 3 or 4 days with bryo in a dose range of 0.1-10 nM showed a heterogenous PE1 response. Stimulatory as well as inhibitory effects on leukemic clonogenic growth were seen within individual specimens depending on dose and preincubation time with no single incubation time or concentration that caused unequivocal common overall inhibition of clonogenic growth in most or all of the samples. Higher doses of bryo also failed to result in specific inhibition of leukemic cells: 4/8 samples showed an increased clonogenic response to 250 nM bryo whereas normal bone marrow progenitor cells were consistently inhibited in their clonogenicity at this dose. A marked similarity, i.e. undulatory effects with increasing bryo concentrations, was found for HL60 leukemic cells. In conclusion, the effects of bryo on clonogenic leukemia cell growth are strongly dependent on scheduling and dose varying between and within individual AML samples. These results caution against in vivo bryo pulse therapy, as currently applied, for treatment of AML. PMID:8947584

  1. Infrared Spectra of Human Breast Tumor Tissue and Experimental Animal Tumors

    NASA Astrophysics Data System (ADS)

    Tolstorozhev, G. B.; Belkov, M. V.; Skornyakov, I. V.; Pekhnyo, V. I.; Kozachkova, A. N.; Tsarik, H. V.; Kutsenko, I. P.; Sharykina, N. I.; Butra, V. A.

    2015-01-01

    We have used Fourier transform IR spectroscopy methods to conduct comparative studies of human breast tumors and sarcoma 180 tumor grafted into mice. The IR spectral parameters used to identify tumor tissue in mice with the sarcoma 180 strain proved to be identical to the parameters for human breast tissue in cancer. In the presence of a malignant tumor in humans, the most intense C=O vibrational bands in the protein molecules are observed in the interval 1710-1680 cm-1. For a benign tumor, in the IR spectra of breast tissue the intense bands are located in the interval 1670-1650 cm-1. We spectroscopically monitored the diagnosis and the chemotherapy process using the model of sarcoma 180 in mice. As the therapeutic drugs, we used synthesized coordination compounds based on palladium complexes with diphosphonic acid derivatives. We demonstrate the promising potential of palladium complexes with zoledronic acid as an effective cytostatic. In therapy using a palladium complex with zoledronic acid, the effect of tumor growth inhibition is accompanied by a change in its spectral characteristics. The parameters of the IR spectra for tumor tissue after treatment are close to those of the IR spectra for healthy tissue.

  2. Very small size proteoliposomes abrogate cross-presentation of tumor antigens by myeloid-derived suppressor cells and induce their differentiation to dendritic cells

    PubMed Central

    2014-01-01

    Background Myeloid-derived suppressor cells (MDSCs) are among the major obstacles that adjuvants for cancer vaccines have to overcome. These cells cross-present tumor-associated antigens (TAA) to naive T lymphocytes with a tolerogenic outcome. Very Small Size Proteoliposomes (VSSP) is used as adjuvant by four therapeutic cancer vaccines currently in Phase I and II clinical trials. We previously found that VSSP reduces the suppressive function of MDSCs, then activating antigen-specific CTL responses in tumor-bearing (TB) mice, with the consequent reduction of tumor growth. However the mechanistic explanation for the immunomodulatory effect of this adjuvant in TB hosts has not been addressed before. Methods TB mice were inoculated with VSSP and MDSCs isolated and characterized by their expression of Arg1 and Nos2 genes by RT-PCR. The effect of VSSP on antigen cross-presentation by MDSCs, regulatory T cells (Tregs) expansion and MDSCs differentiation towards dendritic cells (DCs) was analyzed by FACS. Student’s t test or ANOVA and Tukey’s tests were used for statistical analyses. Results After inoculating VSSP into TB mice, a significant reduction of Arg1 and Nos2 gene expression was observed in recovered MDSCs. Concurrently the ability of these cells to induce down-regulation of CD3ζ chain on T cells was lost. Likewise in mice inoculated with the adjuvant lower percentages of Tregs were detected. In vitro, VSSP treatment was enough to differentiate MDSCs into phenotypically mature DCs, eliminating the former suppressive effect. Noteworthy, in vivo administration of VSSP to OVA-expressing (EG.7) TB mice abrogated this model antigen cross-presentation by splenic MDSCs. Similar results were obtained even when OVA antigen was administered into these TB mice formulated in VSSP. On the contrary, immunization with the same protein in polyI:C did not change the percentage of MDSCs expressing SIINFEKL/H-2Kb complexes, whereas a concomitant injection of VSSP aborted the

  3. Cytokines induce urokinase-dependent adhesion of human myeloid cells. A regulatory role for plasminogen activator inhibitors.

    PubMed Central

    Waltz, D A; Sailor, L Z; Chapman, H A

    1993-01-01

    Differentiation of monocytic precursors often results in adhesive properties thought to be important in migration. In this study, the influence of cytokines, known to induce macrophage differentiation, on the adhesiveness of the monocytic cell line U937 was examined in vitro. Despite development of a macrophage morphology, < 5% of cytokine-stimulated U937 cells were adherent at 24 h. Addition of 1-10 nM urokinase-type plasminogen activator (uPA) induced adherence in the presence of transforming growth factor type beta-1, 1,25-(OH)2 vitamin D3, granulocyte macrophage colony-stimulating factor, or tumor necrosis factor alpha. uPA-dependent adhesiveness was reversible after 24 h of stimulation with cytokines and uPA as adherence was prevented by the subsequent addition of anti-uPA antibodies. Adherence induced by diisopropylfluorophosphate-inactivated uPA was severalfold greater than that seen with active uPA. This difference was largely due to cell-surface turnover of active uPA complexed with plasminogen activator inhibitor (PAI). These data indicate that cytokines prime monocyte progenitors for uPA receptor-mediated signals leading to adherence, continued uPA receptor occupancy is required for adherence, and PAI decreases adherence by promoting clearance of uPA/PAI complexes. Thus the interaction of uPA and PAI at the cell surface, known to affect extracellular matrix proteolysis and hence myeloid cell migration, also regulates adhesion. The coordinated regulation of these two uPA functions by PAI may enhance the migratory potential of monocytic cells. Images PMID:8386190

  4. Human herpesvirus 7 infection of lymphoid and myeloid cell lines transduced with an adenovirus vector containing the CD4 gene.

    PubMed Central

    Yasukawa, M; Inoue, Y; Ohminami, H; Sada, E; Miyake, K; Tohyama, T; Shimada, T; Fujita, S

    1997-01-01

    It has been reported recently that CD4 is a major component of the receptor for human herpesvirus 7 (HHV-7), which has been newly identified as a T-lymphotropic virus. To investigate further the role of CD4 in HHV-7 infection, we examined the susceptibility to HHV-7 infection of various CD4-negative or weakly positive cell lines into which the cDNA for CD4 was transferred using an adenovirus vector (Adex1CACD4). Of 13 cell lines transduced with Adex1CACD4, including T-lymphoid, B-lymphoid, monocytoid, and myeloid cell lines, one T-lymphoid cell line, one monocytoid cell line, and two cell lines established from the blast crisis of chronic myelogenous leukemia showed high susceptibility to HHV-7 infection. Taken together with the results of previous studies, these data suggest strongly that CD4 is a major component of the binding receptor for HHV-7. This study also shows that HHV-7 may be able to infect CD4-positive hematopoietic precursor cells as well as T lymphocytes. PMID:8995705

  5. The Effects of T4 and A3/R Bacteriophages on Differentiation of Human Myeloid Dendritic Cells.

    PubMed

    Bocian, Katarzyna; Borysowski, Jan; Zarzycki, Michał; Pacek, Magdalena; Weber-Dąbrowska, Beata; Machcińska, Maja; Korczak-Kowalska, Grażyna; Górski, Andrzej

    2016-01-01

    Bacteriophages (phages) are viruses of bacteria. Here we evaluated the effects of T4 and A3/R bacteriophages, as well as phage-generated bacterial lysates, on differentiation of human myeloid dendritic cells (DCs) from monocytes. Neither of the phages significantly reduced the expression of markers associated with differentiation of DCs and their role in the activation of T cells (CD40, CD80, CD83, CD86, CD1c, CD11c, MHC II, PD-L1, PD-L2, TLR2, TLR4, and CCR7) and phagocytosis receptors (CD64 and DEC-205). By contrast, bacterial lysate of T4 phage significantly decreased the percentages of DEC-205- and CD1c-positive cells. The percentage of DEC-205-positive cells was also significantly reduced in DCs differentiated in the presence of lysate of A3/R phage. Thus while bacteriophages do not substantially affect differentiation of DCs, some products of phage-induced lysis of bacterial cells may influence the differentiation and potentially also some functions of DCs. Our results have important implications for phage therapy of bacterial infections because during infections monocytes recruited to the site of inflammation are an important source of inflammatory DCs. PMID:27582733

  6. Granulocytic Myeloid-Derived Suppressor Cells Accumulate in Human Placenta and Polarize toward a Th2 Phenotype.

    PubMed

    Köstlin, Natascha; Hofstädter, Kathrin; Ostermeir, Anna-Lena; Spring, Bärbel; Leiber, Anja; Haen, Susanne; Abele, Harald; Bauer, Peter; Pollheimer, Jürgen; Hartl, Dominik; Poets, Christian F; Gille, Christian

    2016-02-01

    Tolerance induction toward the semiallogeneic fetus is crucial to enable a successful pregnancy; its failure is associated with abortion or preterm delivery. Skewing T cell differentiation toward a Th2-dominated phenotype seems to be pivotal in maternal immune adaption, yet underlying mechanisms are incompletely understood. Myeloid-derived suppressor cells (MDSCs) are innate immune cells that mediate T cell suppression and are increased in cord blood of healthy newborns and in peripheral blood of pregnant women. In this study, we demonstrate that granulocytic MDSCs (GR-MDSCs) accumulate in human placenta of healthy pregnancies but are diminished in patients with spontaneous abortions. Placental GR-MDSCs effectively suppressed T cell responses by expression of arginase I and production of reactive oxygen species and were activated at the maternal-fetal interface through interaction with trophoblast cells. Furthermore, GR-MDSCs isolated from placenta polarized CD4(+) T cells toward a Th2 cytokine response. These results highlight a potential role of GR-MDSCs in inducing and maintaining maternal-fetal tolerance and suggest them as a promising target for therapeutic manipulation of pregnancy complications. PMID:26712947

  7. Clinical Significance of Myeloid-Derived Suppressor Cells in Human Immunodeficiency Virus-1/ Hepatitis C Virus-coinfected Patients.

    PubMed

    Lei, A H; Yang, Q; Cai, W P; Liu, Y F; Lan, Y; Qin, A P; Hu, F Y; Zhou, J

    2016-06-01

    Myeloid-derived suppressor cells (MDSCs) are known to accumulate during chronic viral infection, including human immunodeficiency virus-1 (HIV-1) and hepatitis C virus (HCV) infection, and play a critical role in suppressing immune responses. However, the role of MDSCs in HIV/HCV coinfection is unclear. Here, we observed a dramatic increase in monocytic MDSCs (M-MDSCs) level in the peripheral blood of HIV/HCV-coinfected patients compared to that of healthy controls; the level of M-MDSCs proportion in coinfection was not higher than that in HIV or HCV monoinfection. Interestingly, we found the M-MDSCs level in coinfected patients correlated well with CD4(+) T cell loss (r = -0.5680; P = 0.0058), HIV-1 load (r = 0.6011; P = 0.0031), HCV load (r = 0.6288; P = 0.0017) and activated CD38(+) T cells (r = 0.5139; P = 0.0144). Initiation of highly active antiretroviral therapy considerably reduced both M-MDSCs and CD8(+) CD38(+) -activated T cell proportion in coinfected patients, and they showed a parallel course of decline. Thus, our results suggest that HIV-1 infection and high chronic immune activation may contribute to the expansion of M-MDSCs and accelerate the disease progression in HIV/HCV-coinfected patients. PMID:26972443

  8. Critical involvement of the α(1,2)-fucosyltransferase in multidrug resistance of human chronic myeloid leukemia.

    PubMed

    Che, Yuxuan; Ren, Xing; Xu, Liye; Ding, Xiaolei; Zhang, Xuan; Sun, Xiuhua

    2016-05-01

    The fucosyltransferases are key enzymes in cell surface antigen synthesis during multidrug resistance (MDR) development. The aim of the present study was to analyze the alteration of α(1,2)-fucosyltransferase involved in MDR development in human chronic myeloid leukemia (CML). FUT1 was overexpressed in three CML/MDR cell lines and peripheral blood mononuclear cells (PBMC) of CML patients. However, no significant changes of FUT2 were observed. The altered levels of FUT1 had a significant impact on the phenotypic variation of MDR of K562 and K562/ADR cells, the activity of EGFR/MAPK pathway and P-glycoprotein (P-gp) expression. Blocking the EGFR/MAPK pathway by its specific inhibitor PD153035 or EGFR small interfering RNA (siRNA) resulted in the reduced MDR of K562/ADR cells. This study indicated that α(1,2)-fucosyltransferase involved in the development of MDR of CML cells probably through FUT1 regulated the activity of EGFR/MAPK signaling pathway and the expression of P-gp. PMID:26986216

  9. The Effects of T4 and A3/R Bacteriophages on Differentiation of Human Myeloid Dendritic Cells

    PubMed Central

    Bocian, Katarzyna; Borysowski, Jan; Zarzycki, Michał; Pacek, Magdalena; Weber-Dąbrowska, Beata; Machcińska, Maja; Korczak-Kowalska, Grażyna; Górski, Andrzej

    2016-01-01

    Bacteriophages (phages) are viruses of bacteria. Here we evaluated the effects of T4 and A3/R bacteriophages, as well as phage-generated bacterial lysates, on differentiation of human myeloid dendritic cells (DCs) from monocytes. Neither of the phages significantly reduced the expression of markers associated with differentiation of DCs and their role in the activation of T cells (CD40, CD80, CD83, CD86, CD1c, CD11c, MHC II, PD-L1, PD-L2, TLR2, TLR4, and CCR7) and phagocytosis receptors (CD64 and DEC-205). By contrast, bacterial lysate of T4 phage significantly decreased the percentages of DEC-205- and CD1c-positive cells. The percentage of DEC-205-positive cells was also significantly reduced in DCs differentiated in the presence of lysate of A3/R phage. Thus while bacteriophages do not substantially affect differentiation of DCs, some products of phage-induced lysis of bacterial cells may influence the differentiation and potentially also some functions of DCs. Our results have important implications for phage therapy of bacterial infections because during infections monocytes recruited to the site of inflammation are an important source of inflammatory DCs. PMID:27582733

  10. Human chronic myeloid leukemia stem cells are insensitive to imatinib despite inhibition of BCR-ABL activity

    PubMed Central

    Corbin, Amie S.; Agarwal, Anupriya; Loriaux, Marc; Cortes, Jorge; Deininger, Michael W.; Druker, Brian J.

    2010-01-01

    Imatinib therapy, which targets the oncogene product BCR-ABL, has transformed chronic myeloid leukemia (CML) from a life-threatening disease into a chronic condition. Most patients, however, harbor residual leukemia cells, and disease recurrence usually occurs when imatinib is discontinued. Although various mechanisms to explain leukemia cell persistence have been proposed, the critical question from a therapeutic standpoint — whether disease persistence is BCR-ABL dependent or independent — has not been answered. Here, we report that human CML stem cells do not depend on BCR-ABL activity for survival and are thus not eliminated by imatinib therapy. Imatinib inhibited BCR-ABL activity to the same degree in all stem (CD34+CD38–, CD133+) and progenitor (CD34+CD38+) cells and in quiescent and cycling progenitors from newly diagnosed CML patients. Although short-term in vitro imatinib treatment reduced the expansion of CML stem/progenitors, cytokine support permitted growth and survival in the absence of BCR-ABL activity that was comparable to that of normal stem/progenitor counterparts. Our findings suggest that primitive CML cells are not oncogene addicted and that therapies that biochemically target BCR-ABL will not eliminate CML stem cells. PMID:21157039

  11. Targeted Radionuclide Therapy of Human Tumors

    PubMed Central

    Gudkov, Sergey V.; Shilyagina, Natalya Yu.; Vodeneev, Vladimir A.; Zvyagin, Andrei V.

    2015-01-01

    Targeted radionuclide therapy is one of the most intensively developing directions of nuclear medicine. Unlike conventional external beam therapy, the targeted radionuclide therapy causes less collateral damage to normal tissues and allows targeted drug delivery to a clinically diagnosed neoplastic malformations, as well as metastasized cells and cellular clusters, thus providing systemic therapy of cancer. The methods of targeted radionuclide therapy are based on the use of molecular carriers of radionuclides with high affinity to antigens on the surface of tumor cells. The potential of targeted radionuclide therapy has markedly grown nowadays due to the expanded knowledge base in cancer biology, bioengineering, and radiochemistry. In this review, progress in the radionuclide therapy of hematological malignancies and approaches for treatment of solid tumors is addressed. PMID:26729091

  12. Purified group X secretory phospholipase A(2) induced prominent release of arachidonic acid from human myeloid leukemia cells.

    PubMed

    Hanasaki, K; Ono, T; Saiga, A; Morioka, Y; Ikeda, M; Kawamoto, K; Higashino, K; Nakano, K; Yamada, K; Ishizaki, J; Arita, H

    1999-11-26

    Group X secretory phospholipase A(2) (sPLA(2)-X) possesses several structural features characteristic of both group IB and IIA sPLA(2)s (sPLA(2)-IB and -IIA) and is postulated to be involved in inflammatory responses owing to its restricted expression in the spleen and thymus. Here, we report the purification of human recombinant COOH-terminal His-tagged sPLA(2)-X, the preparation of its antibody, and the purification of native sPLA(2)-X. The affinity-purified sPLA(2)-X protein migrated as various molecular species of 13-18 kDa on SDS-polyacrylamide gels, and N-glycosidase F treatment caused shifts to the 13- and 14-kDa bands. NH(2)-terminal amino acid sequencing analysis revealed that the 13-kDa form is a putative mature sPLA(2)-X and the 14-kDa protein possesses a propeptide of 11 amino acid residues attached at the NH(2) termini of the mature protein. Separation with reverse-phase high performance liquid chromatography revealed that N-linked carbohydrates are not required for the enzymatic activity and pro-sPLA(2)-X has a relatively weak potency compared with the mature protein. The mature sPLA(2)-X induced the release of arachidonic acid from phosphatidylcholine more efficiently than other human sPLA(2) groups (IB, IIA, IID, and V) and elicited a prompt and marked release of arachidonic acid from human monocytic THP-1 cells compared with sPLA(2)-IB and -IIA with concomitant production of prostaglandin E(2). A prominent release of arachidonic acid was also observed in sPLA(2)-X-treated human U937 and HL60 cells. Immunohistochemical analysis of human lung preparations revealed its expression in alveolar epithelial cells. These results indicate that human sPLA(2)-X is a unique N-glycosylated sPLA(2) that releases arachidonic acid from human myeloid leukemia cells more efficiently than sPLA(2)-IB and -IIA. PMID:10567392

  13. Wilms Tumor 1 Expression and Pre-emptive Immunotherapy in Patients with Acute Myeloid Leukemia Undergoing an Allogeneic Hemopoietic Stem Cell Transplantation.

    PubMed

    Di Grazia, Carmen; Pozzi, Sarah; Geroldi, Simona; Grasso, Raffaella; Miglino, Maurizio; Colombo, Nicoletta; Tedone, Elisabetta; Luchetti, Silvia; Lamparelli, Teresa; Gualandi, Francesca; Ibatici, Adalberto; Bregante, Stefania; Van Lint, Maria Teresa; Raiola, Anna Maria; Dominietto, Alida; Varaldo, Riccardo; Galaverna, Federica; Ghiso, Anna; Sica, Simona; Bacigalupo, Andrea

    2016-07-01

    Minimal residual disease (MRD) was monitored by Wilms tumor 1 (WT1) expression in 207 patients with acute myeloid leukemia (AML) after an allogeneic hemopoietic stem cell transplantation (HSCT) as a trigger to initiate pre-emptive immunotherapy (IT) with cyclosporin discontinuation and/or donor lymphocyte infusion. The trigger for IT was WT1 ≥ 180 copies/10(4) Abelson cells in marrow cells in the first group of 122 patients (WT1-180) and ≥ 100 copies in a subsequent group of 85 patients (WT1-100). Forty patients received IT. The cumulative incidence (CI) of relapse was 76% in WT1-180 (n = 17) versus 29% in WT1-100 patients (n = 23) receiving IT (P = .006); the leukemia-free survival from MRD positivity was 23% versus 74%, respectively (P = .003). We then looked at the entire AML patient population (n = 207). WT1-180 and WT1-100 patients were comparable for disease phase and age. The overall 4-year CI of transplantation-related mortality was 13% in both groups; the CI of leukemia relapse was 38% in the WT1-180 and 28% in the WT1-100 patients (P = .05) and leukemia-free survival was 56% versus 48%, respectively (P = .07). In conclusion, we suggests that WT1-based pre-emptive immunotherapy is feasible in patients with undergoing an allogeneic HSCT. The protective effect on relapse is greater when IT is triggered at lower levels of WT1. PMID:26970379

  14. Broad distribution of the multidrug resistance-related vault lung resistance protein in normal human tissues and tumors.

    PubMed

    Izquierdo, M A; Scheffer, G L; Flens, M J; Giaccone, G; Broxterman, H J; Meijer, C J; van der Valk, P; Scheper, R J

    1996-03-01

    Multidrug resistance (MDR) to anticancer drugs is a major cause of treatment failure in cancer. The lung resistance protein LRP is a newly described protein related to MDR in several in vitro models. LRP has been shown to be a strong predictor of poor response to chemotherapy and prognosis in acute myeloid leukemia and in ovarian carcinoma patients. Recently, based on a 57% and 88% amino acid identity with major vault proteins from Dictyostelium discoideum and Rattus norvegicus, respectively, we identified LRP as the human major vault protein, the main component of highly conserved cellular organelles named vaults. We have studied the immunohistochemical expression of LRP in freshly frozen normal human tissues and 174 cancer specimens of 28 tumor types. LRP was broadly distributed in normal and malignant cells, but distinct patterns of expression were noticed. High LRP expression was seen in bronchus, digestive tract, renal proximal tubules, keratinocytes, macrophages, and adrenal cortex whereas varying ing levels were observed in other organs. LRP was detected in all tumor types examined, but its frequency varied, fairly reflecting the chemosensitivity of different cancers. For example, low rates of LRP positivity were seen in testicular cancer, neuroblastoma, and acute myeloid leukemia; intermediate in ovarian cancer; and high in colon, renal, and pancreatic carcinomas. The wide occurrence of LRP in normal and transformed cells in humans, its similar distribution to that of vaults in other species, as well as the high level of conservation among eukaryotic cells of both the amino acid sequence of the major vault protein and the composition and structure of vaults, suggest that vault function is important to eukaryotic cells. PMID:8774142

  15. A Big Bang model of human colorectal tumor growth.

    PubMed

    Sottoriva, Andrea; Kang, Haeyoun; Ma, Zhicheng; Graham, Trevor A; Salomon, Matthew P; Zhao, Junsong; Marjoram, Paul; Siegmund, Kimberly; Press, Michael F; Shibata, Darryl; Curtis, Christina

    2015-03-01

    What happens in early, still undetectable human malignancies is unknown because direct observations are impractical. Here we present and validate a 'Big Bang' model, whereby tumors grow predominantly as a single expansion producing numerous intermixed subclones that are not subject to stringent selection and where both public (clonal) and most detectable private (subclonal) alterations arise early during growth. Genomic profiling of 349 individual glands from 15 colorectal tumors showed an absence of selective sweeps, uniformly high intratumoral heterogeneity (ITH) and subclone mixing in distant regions, as postulated by our model. We also verified the prediction that most detectable ITH originates from early private alterations and not from later clonal expansions, thus exposing the profile of the primordial tumor. Moreover, some tumors appear 'born to be bad', with subclone mixing indicative of early malignant potential. This new model provides a quantitative framework to interpret tumor growth dynamics and the origins of ITH, with important clinical implications. PMID:25665006

  16. Benzene Metabolite 1,2,4-Benzenetriol Induces Halogenated DNA and Tyrosines Representing Halogenative Stress in the HL-60 Human Myeloid Cell Line

    PubMed Central

    Miyahara, Emiko; Horiuchi, Masahisa; Izumo, Kimiko; Okamoto, Yasuhiro; Kawai, Yoshichika; Kawano, Yoshifumi; Takeuchi, Toru

    2011-01-01

    Background: Although benzene is known to be myelotoxic and to cause myeloid leukemia in humans, the mechanism has not been elucidated. Objectives: We focused on 1,2,4-benzenetriol (BT), a benzene metabolite that generates reactive oxygen species (ROS) by autoxidation, to investigate the toxicity of benzene leading to leukemogenesis. Methods: After exposing HL-60 human myeloid cells to BT, we investigated the cellular effects, including apoptosis, ROS generation, DNA damage, and protein damage. We also investigated how the cellular effects of BT were modified by hydrogen peroxide (H2O2) scavenger catalase, hypochlorous acid (HOCl) scavenger methionine, and 4-aminobenzoic acid hydrazide (ABAH), a myeloperoxidase (MPO)-specific inhibitor. Results: BT increased the levels of apoptosis and ROS, including superoxide (O2•−), H2O2, HOCl, and the hydroxyl radical (•OH). Catalase, ABAH, and methionine each inhibited the increased apoptosis caused by BT, and catalase and ABAH inhibited increases in HOCl and •OH. Although BT exposure increased halogenated DNA, this increase was inhibited by catalase, methionine, and ABAH. BT exposure also increased the amount of halogenated tyrosines; however, it did not increase 8-oxo-deoxyguanosine. Conclusions: We suggest that BT increases H2O2 intracellularly; this H2O2 is metabolized to HOCl by MPO, and this HOCl results in possibly cytotoxic binding of chlorine to DNA. Because myeloid cells copiously express MPO and because halogenated DNA may induce both genetic and epigenetic changes that contribute to carcinogenesis, halogenative stress may account for benzene-induced bone marrow disorders and myeloid leukemia. PMID:21859636

  17. SKI knockdown inhibits human melanoma tumor growth in vivo.

    PubMed

    Chen, Dahu; Lin, Qiushi; Box, Neil; Roop, Dennis; Ishii, Shunsuke; Matsuzaki, Koichi; Fan, Tao; Hornyak, Thomas J; Reed, Jon A; Stavnezer, Ed; Timchenko, Nikolai A; Medrano, Estela E

    2009-12-01

    The SKI protein represses the TGF-beta tumor suppressor pathway by associating with the Smad transcription factors. SKI is upregulated in human malignant melanoma tumors in a disease-progression manner and its overexpression promotes proliferation and migration of melanoma cells in vitro. The mechanisms by which SKI antagonizes TGF-beta signaling in vivo have not been fully elucidated. Here we show that human melanoma cells in which endogenous SKI expression was knocked down by RNAi produced minimal orthotopic tumor xenograft nodules that displayed low mitotic rate and prominent apoptosis. These minute tumors exhibited critical signatures of active TGF-beta signaling including high levels of nuclear Smad3 and p21(Waf-1), which are not found in the parental melanomas. To understand how SKI promotes tumor growth we used gain- and loss-of-function approaches and found that simultaneously to blocking the TGF-beta-growth inhibitory pathway, SKI promotes the switch of Smad3 from tumor suppression to oncogenesis by favoring phosphorylations of the Smad3 linker region in melanoma cells but not in normal human melanocytes. In this context, SKI is required for preventing TGF-beta-mediated downregulation of the oncogenic protein c-MYC, and for inducing the plasminogen activator inhibitor-1, a mediator of tumor growth and angiogenesis. Together, the results indicate that SKI exploits multiple regulatory levels of the TGF-beta pathway and its deficiency restores TGF-beta tumor suppressor and apoptotic activities in spite of the likely presence of oncogenic mutations in melanoma tumors. PMID:19845874

  18. Type I IFNs induce anti-tumor polarization of tumor associated neutrophils in mice and human.

    PubMed

    Andzinski, Lisa; Kasnitz, Nadine; Stahnke, Stephanie; Wu, Ching-Fang; Gereke, Marcus; von Köckritz-Blickwede, Maren; Schilling, Bastian; Brandau, Sven; Weiss, Siegfried; Jablonska, Jadwiga

    2016-04-15

    The importance of tumor associated neutrophils (TANs) in cancer development is in the meantime well established. Numerous of clinical data document the adverse prognostic effects of neutrophil infiltration in solid tumors. However, certain tumor therapies need functional neutrophils to be effective, suggesting altered neutrophil polarization associated with different outcomes for cancer patients. Therefore, modulation of neutrophilic phenotypes represents a potent therapeutic option, but factors mediating neutrophil polarization are still poorly defined. In this manuscript we provide evidence that type I IFNs alter neutrophilic phenotype into anti-tumor, both in mice and human. In the absence of IFN-β, pro-tumor properties, such as reduced tumor cytotoxicity with low neutrophil extracellular traps (NETs) expression, low ICAM1 and TNF-α expression, dominated neutrophil phenotypes in primary lesion and premetastatic lung. Interestingly, such neutrophils have significantly prolonged life-span. Notably, interferon therapy in mice altered TAN polarization towards anti-tumor N1. Similar changes in neutrophil activation could be observed in melanoma patients undergoing type I IFN therapy. Altogether, these data highlight the therapeutic potential of interferons, suggesting optimization of its clinical use as potent anti-tumor agent. PMID:26619320

  19. Human Tumor Antigens and Cancer Immunotherapy

    PubMed Central

    Vigneron, Nathalie

    2015-01-01

    With the recent developments of adoptive T cell therapies and the use of new monoclonal antibodies against the immune checkpoints, immunotherapy is at a turning point. Key players for the success of these therapies are the cytolytic T lymphocytes, which are a subset of T cells able to recognize and kill tumor cells. Here, I review the nature of the antigenic peptides recognized by these T cells and the processes involved in their presentation. I discuss the importance of understanding how each antigenic peptide is processed in the context of immunotherapy and vaccine delivery. PMID:26161423

  20. A nylon wool filter coated with human immunoglobulin for rapid depletion of monocytes and myeloid cells from peripheral blood stem cell transplants.

    PubMed

    Kwekkeboom, J; Buurman, D E; Ploemacher, R E; Baars, J W; Loos, H A; Slaper-Cortenbach, I C

    1998-05-01

    The aim of this study was to develop an inexpensive method for reducing the number of differentiated cells from granulocyte colony-stimulating factor-mobilized leukocytapheresis products (LPs) containing peripheral blood stem cells. Analysis of LPs showed the presence of significant numbers of monocytes and myeloid cells. The myeloid cells represented largely immature stages of the granulocyte lineage (myelocytes and metamyelocytes). We investigated whether these cells could be selectively depleted by filtration over nylon wool. Filtration of LP samples over nylon wool in a medium containing fetal calf serum resulted in variable but on average low yields of CD34+ cells (48 +/- 30%; n=13) and strongly variable depletions of myeloid cells. The adherence of CD34+ cells to the polyamide fiber was partially mediated by activated platelets that were present in the LPs. Removal of platelets by counterflow centrifugal elutriation before filtration resulted in increased yields of CD34+ cells in the filtrates (65 +/- 13%; n=10). The yield of progenitor cells was similarly enhanced when trisodium citrate, a chelating substance, was added to the filtration medium. Adherence of the myeloid cells to the nylon fiber was promoted by preincubation of the columns with human immunoglobulin (Ig) (2 mg/mL). Small-scale filtrations of LP samples in the presence of trisodium citrate over columns with Ig-coated nylon wool resulted in removal of 96 +/- 4% of the monocytes and 74 +/- 18% of the myeloid cells, with a yield of 71 +/- 15% CD34+ cells and 67 +/- 10% granulocyte-monocyte colony-forming units (CFU-GM) (n=23). There was no loss of primitive stem cells during the procedure: the yield of late-appearing cobblestone area-forming cells (CAFCs, week 6) was 110 +/- 30% (n=4). CFU-GM production per CAFC-derived clone was unchanged upon filtration, indicating that the quality of stem cells was not affected. Moreover, the proportions of CD34+ cells expressing a primitive immunophenotype (CD

  1. Lrig1 Expression in Human Sebaceous Gland Tumors

    PubMed Central

    Pünchera, Jöri; Barnes, Laurent; Kaya, Gürkan

    2016-01-01

    Background Sebaceous glands contribute significantly to the barrier functions of the skin. However, little is known about their homeostasis and tumorigenesis. Recently, increased expression of stem cell marker Lrig1 has been reported in sebaceous carcinoma-like tumors of K14ΔNLef1 transgenic mice. In this study, we analyzed the Lrig1 expression in human sebaceous tumors. Methods Twenty-eight formalin-fixed paraffin-embedded sebaceous tumor specimens (7 sebaceous hyperplasias, 7 sebaceous adenomas, 10 sebaceomas and 4 sebaceous carcinomas) were stained with anti-Lrig1, anti-CD44v3 and anti-Ki67 antibody. Results Four (100%) sebaceous carcinomas, 8 (80%) sebaceomas, 3 (43%) sebaceous adenomas and no sebaceous hyperplasia showed Lrig1 overexpression. Discussion and Conclusion Lrig1 is a known tumor suppressor gene and is usually considered to be an indicator of poorly aggressive tumors. In human sebaceous tumors, the stronger Lrig1 staining in sebaceous carcinoma compared to other sebaceous tumors might be a feature of an advanced stage in tumorigenesis and a bad prognosis. In our study, 100% of sebaceous carcinomas revealed Lrig1 overexpression. We propose that Lrig1 may be used as a possible new marker of poorly differentiated sebaceous carcinoma. PMID:27504445

  2. Porphyromonas gingivalis Evasion of Autophagy and Intracellular Killing by Human Myeloid Dendritic Cells Involves DC-SIGN-TLR2 Crosstalk

    PubMed Central

    El-Awady, Ahmed R.; Miles, Brodie; Scisci, Elizabeth; Kurago, Zoya B.; Palani, Chithra D.; Arce, Roger M.; Waller, Jennifer L.; Genco, Caroline A.; Slocum, Connie; Manning, Matthew; Schoenlein, Patricia V.; Cutler, Christopher W.

    2015-01-01

    Signaling via pattern recognition receptors (PRRs) expressed on professional antigen presenting cells, such as dendritic cells (DCs), is crucial to the fate of engulfed microbes. Among the many PRRs expressed by DCs are Toll-like receptors (TLRs) and C-type lectins such as DC-SIGN. DC-SIGN is targeted by several major human pathogens for immune-evasion, although its role in intracellular routing of pathogens to autophagosomes is poorly understood. Here we examined the role of DC-SIGN and TLRs in evasion of autophagy and survival of Porphyromonas gingivalis in human monocyte-derived DCs (MoDCs). We employed a panel of P. gingivalis isogenic fimbriae deficient strains with defined defects in Mfa-1 fimbriae, a DC-SIGN ligand, and FimA fimbriae, a TLR2 agonist. Our results show that DC-SIGN dependent uptake of Mfa1+P. gingivalis strains by MoDCs resulted in lower intracellular killing and higher intracellular content of P. gingivalis. Moreover, Mfa1+P. gingivalis was mostly contained within single membrane vesicles, where it survived intracellularly. Survival was decreased by activation of TLR2 and/or autophagy. Mfa1+P. gingivalis strain did not induce significant levels of Rab5, LC3-II, and LAMP1. In contrast, P. gingivalis uptake through a DC-SIGN independent manner was associated with early endosomal routing through Rab5, increased LC3-II and LAMP-1, as well as the formation of double membrane intracellular phagophores, a characteristic feature of autophagy. These results suggest that selective engagement of DC-SIGN by Mfa-1+P. gingivalis promotes evasion of antibacterial autophagy and lysosome fusion, resulting in intracellular persistence in myeloid DCs; however TLR2 activation can overcome autophagy evasion and pathogen persistence in DCs. PMID:25679217

  3. Induction of apoptosis by Cordyceps militaris fraction in human chronic myeloid leukemia K562 cells involved with mitochondrial dysfunction

    PubMed Central

    Tian, Tian; Song, Liyan; Zheng, Qin; Hu, Xianjing; Yu, Rongmin

    2014-01-01

    Background: Cordyceps militaris is widely used for various ethno medical conditions including cancer and inflammation complications in traditional Chinese medicine. Objective: To investigate the in vitro antitumor activity of Cordyceps militaris fraction (CMF) and the molecular mechanism underlying the apoptosis it induces in human chronic myeloid leukemia K562 cells. Materials and Methods: CMF was prepared according to our previous report. Cell viability was assessed by MTT assay. The rate of apoptosis, distribution of cell cycle and loss of mitochondrial membrane potential were measured by flow cytometry. Caspase activities were analyzed by Western blot and oxygen consumption rate was recorded using the Oxytherm system. Results: The results demonstrated that CMF triggered growth inhibition in K562 cells with only minor toxicity on a normal human cell line and inhibited the proliferation of K562 cells in a dose- and time-dependent manner with IC50 value of 34.1 ± 2.0 μg/ml after 48 h incubation. This most likely resulted from cell cycle arrest at the S phase and the induction of apoptosis. In addition, CMF induced activation of caspase-3 and subsequent cleavage of poly ADP-ribose polymerase (PARP). The caspase signals may originate from mitochondrial dysfunction, which was supported by the finding of decreased mitochondria transmembrance potential and the lower oxygen consumption rate. Conclusion: CMF possessed the in vitro antitumor effect on K562 cells and CMF-induced apoptosis might be involved by the mitochondrial dysfunction and valuable to research and develop as a potential antitumor agency. PMID:25210321

  4. Expanded Numbers of Circulating Myeloid Dendritic Cells in Patent Human Filarial Infection Reflect Lower CCR1 Expression

    PubMed Central

    Semnani, Roshanak Tolouei; Mahapatra, Lily; Dembele, Benoit; Konate, Siaka; Metenou, Simon; Dolo, Housseini; Coulibaly, Michel E.; Soumaoro, Lamine; Coulibaly, Siaka Y.; Sanogo, Dramane; Doumbia, Salif Seriba; Diallo, Abdallah A.; Traoré, Sekou F.; Klion, Amy; Nutman, Thomas B.; Mahanty, Siddhartha

    2012-01-01

    APC dysfunction has been postulated to mediate some of the parasite-specific T cell unresponsiveness seen in patent filarial infection. We have shown that live microfilariae of Brugia malayi induce caspase-dependent apoptosis in human monocyte-derived dendritic cells (DCs) in vitro. This study addresses whether apoptosis observed in vitro extends to patent filarial infections in humans and is reflected in the number of circulating myeloid DCs (mDCs; CD11c−CD123lo) in peripheral blood of infected microfilaremic individuals. Utilizing flow cytometry to identify DC subpopulations (mDCs and plasmacytoid DCs [pDCs]) based on expression of CD11c and CD123, we found a significant increase in numbers of circulating mDCs (CD11c+CD123lo) in filaria-infected individuals compared with uninfected controls from the same filaria-endemic region of Mali. Total numbers of pDCs, monocytes, and lymphocytes did not differ between the two groups. To investigate potential causes of differences in mDC numbers between the two groups, we assessed chemokine receptor expression on mDCs. Our data indicate that filaria-infected individuals had a lower percentage of circulating CCR1+ mDCs and a higher percentage of circulating CCR5+ mDCs and pDCs. Finally, live microfilariae of B. malayi were able to downregulate cell-surface expression of CCR1 on monocyte-derived DCs and diminish their calcium flux in response to stimulation by a CCR1 ligand. These findings suggest that microfilaria are capable of altering mDC migration through downregulation of expression of some chemokine receptors and their signaling functions. These observations have major implications for regulation of immune responses to these long-lived parasites. PMID:20956349

  5. Expanded numbers of circulating myeloid dendritic cells in patent human filarial infection reflect lower CCR1 expression.

    PubMed

    Semnani, Roshanak Tolouei; Mahapatra, Lily; Dembele, Benoit; Konate, Siaka; Metenou, Simon; Dolo, Housseini; Coulibaly, Michel E; Soumaoro, Lamine; Coulibaly, Siaka Y; Sanogo, Dramane; Seriba Doumbia, Salif; Diallo, Abdallah A; Traoré, Sekou F; Klion, Amy; Nutman, Thomas B; Mahanty, Siddhartha

    2010-11-15

    APC dysfunction has been postulated to mediate some of the parasite-specific T cell unresponsiveness seen in patent filarial infection. We have shown that live microfilariae of Brugia malayi induce caspase-dependent apoptosis in human monocyte-derived dendritic cells (DCs) in vitro. This study addresses whether apoptosis observed in vitro extends to patent filarial infections in humans and is reflected in the number of circulating myeloid DCs (mDCs; CD11c(-)CD123(lo)) in peripheral blood of infected microfilaremic individuals. Utilizing flow cytometry to identify DC subpopulations (mDCs and plasmacytoid DCs [pDCs]) based on expression of CD11c and CD123, we found a significant increase in numbers of circulating mDCs (CD11c(+)CD123(lo)) in filaria-infected individuals compared with uninfected controls from the same filaria-endemic region of Mali. Total numbers of pDCs, monocytes, and lymphocytes did not differ between the two groups. To investigate potential causes of differences in mDC numbers between the two groups, we assessed chemokine receptor expression on mDCs. Our data indicate that filaria-infected individuals had a lower percentage of circulating CCR1(+) mDCs and a higher percentage of circulating CCR5(+) mDCs and pDCs. Finally, live microfilariae of B. malayi were able to downregulate cell-surface expression of CCR1 on monocyte-derived DCs and diminish their calcium flux in response to stimulation by a CCR1 ligand. These findings suggest that microfilaria are capable of altering mDC migration through downregulation of expression of some chemokine receptors and their signaling functions. These observations have major implications for regulation of immune responses to these long-lived parasites. PMID:20956349

  6. MUC-1 Tumor Antigen Agonist Epitopes for Enhancing T-cell Responses to Human Tumors | NCI Technology Transfer Center | TTC

    Cancer.gov

    Scientists at NIH have identified 7 new agonist epitopes of the MUC-1 tumor associated antigen. Compared to their native epitope counterparts, peptides reflecting these agonist epitopes have been shown to enhance the generation of human tumor cells, which in turn have a greater ability to kill human tumor cells endogenously expressing the native MUC-1 epitope.

  7. Comprehensive molecular portraits of human breast tumors

    PubMed Central

    2012-01-01

    Summary We analyzed primary breast cancers by genomic DNA copy number arrays, DNA methylation, exome sequencing, mRNA arrays, microRNA sequencing and reverse phase protein arrays. Our ability to integrate information across platforms provided key insights into previously-defined gene expression subtypes and demonstrated the existence of four main breast cancer classes when combining data from five platforms, each of which shows significant molecular heterogeneity. Somatic mutations in only three genes (TP53, PIK3CA and GATA3) occurred at > 10% incidence across all breast cancers; however, there were numerous subtype-associated and novel gene mutations including the enrichment of specific mutations in GATA3, PIK3CA and MAP3K1 with the Luminal A subtype. We identified two novel protein expression-defined subgroups, possibly contributed by stromal/microenvironmental elements, and integrated analyses identified specific signaling pathways dominant in each molecular subtype including a HER2/p-HER2/HER1/p-HER1 signature within the HER2-Enriched expression subtype. Comparison of Basal-like breast tumors with high-grade Serous Ovarian tumors showed many molecular commonalities, suggesting a related etiology and similar therapeutic opportunities. The biologic finding of the four main breast cancer subtypes caused by different subsets of genetic and epigenetic abnormalities raises the hypothesis that much of the clinically observable plasticity and heterogeneity occurs within, and not across, these major biologic subtypes of breast cancer. PMID:23000897

  8. Bioengineered models of solid human tumors for cancer research

    PubMed Central

    Marturano-Kruik, Alessandro; Villasante, Aranzazu; Vunjak-Novakovic, Gordana

    2016-01-01

    Summary The lack of controllable in vitro models that can recapitulate the features of solid tumors such as Ewing’s sarcoma limits our understanding of the tumor initiation and progression and impedes the development of new therapies. Cancer research still relies of the use of simple cell culture, tumor spheroids, and small animals. Tissue-engineered tumor models are now being grown in vitro to mimic the actual tumors in patients. Recently, we have established a new protocol for bioengineering the Ewing’s sarcoma, by infusing tumor cell aggregates into the human bone engineered from the patient’s mesenchymal stem cells. The bone niche allows crosstalk between the tumor cells, osteoblasts and supporting cells of the bone, extracellular matrix and the tissue microenvironment. The bioreactor platform used in these experiments also allows the implementation of physiologically relevant mechanical signals. Here, we describe a method to build an in vitro model of Ewing’s sarcoma that mimics the key properties of the native tumor and provides the tissue context and physical regulatory signals. PMID:27115504

  9. Normal ABL1 is a tumor suppressor and therapeutic target in human and mouse leukemias expressing oncogenic ABL1 kinases.

    PubMed

    Dasgupta, Yashodhara; Koptyra, Mateusz; Hoser, Grazyna; Kantekure, Kanchan; Roy, Darshan; Gornicka, Barbara; Nieborowska-Skorska, Margaret; Bolton-Gillespie, Elisabeth; Cerny-Reiterer, Sabine; Müschen, Markus; Valent, Peter; Wasik, Mariusz A; Richardson, Christine; Hantschel, Oliver; van der Kuip, Heiko; Stoklosa, Tomasz; Skorski, Tomasz

    2016-04-28

    Leukemias expressing constitutively activated mutants of ABL1 tyrosine kinase (BCR-ABL1, TEL-ABL1, NUP214-ABL1) usually contain at least 1 normal ABL1 allele. Because oncogenic and normal ABL1 kinases may exert opposite effects on cell behavior, we examined the role of normal ABL1 in leukemias induced by oncogenic ABL1 kinases. BCR-ABL1-Abl1(-/-) cells generated highly aggressive chronic myeloid leukemia (CML)-blast phase-like disease in mice compared with less malignant CML-chronic phase-like disease from BCR-ABL1-Abl1(+/+) cells. Additionally, loss of ABL1 stimulated proliferation and expansion of BCR-ABL1 murine leukemia stem cells, arrested myeloid differentiation, inhibited genotoxic stress-induced apoptosis, and facilitated accumulation of chromosomal aberrations. Conversely, allosteric stimulation of ABL1 kinase activity enhanced the antileukemia effect of ABL1 tyrosine kinase inhibitors (imatinib and ponatinib) in human and murine leukemias expressing BCR-ABL1, TEL-ABL1, and NUP214-ABL1. Therefore, we postulate that normal ABL1 kinase behaves like a tumor suppressor and therapeutic target in leukemias expressing oncogenic forms of the kinase. PMID:26864341

  10. Molecular pathways: myeloid complicity in cancer.

    PubMed

    Stromnes, Ingunn M; Greenberg, Philip D; Hingorani, Sunil R

    2014-10-15

    Cancer-induced inflammation results in accumulation of myeloid cells. These myeloid cells include progenitors and progeny of monocytes, granulocytes, macrophages, and dendritic cells. It has become increasingly evident that tumor-dependent factors can condition myeloid cells toward an immunosuppressive and protumorigenic phenotype. Thus, myeloid cells are not simply bystanders in malignancy or barometers of disease burden. Reflecting their dynamic and plastic nature, myeloid cells manifest a continuum of cellular differentiation and are intimately involved at all stages of neoplastic progression. They can promote tumorigenesis through both immune-dependent and -independent mechanisms and can dictate response to therapies. A greater understanding of the inherent plasticity and relationships among myeloid subsets is needed to inform therapeutic targeting. New clinical trials are being designed to modulate the activities of myeloid cells in cancer, which may be essential to maximize the efficacy of both conventional cytotoxic and immune-based therapies for solid tumors. Clin Cancer Res; 20(20); 5157-70. ©2014 AACR. PMID:25047706