| 1. |
- Grauers Wiktorin, Hanna, 1990, et al.
(författare)
-
Histamine targets myeloid-derived suppressor cells and improves the anti-tumor efficacy of PD-1/PD-L1 checkpoint blockade
- 2019
-
Ingår i: Cancer Immunology Immunotherapy. - : Springer Science and Business Media LLC. - 0340-7004 .- 1432-0851. ; 68:2, s. 163-174
-
Tidskriftsartikel (refereegranskat)abstract
- Myeloid-derived suppressor cells (MDSCs) are immature monocytes and granulocytes that impede immune-mediated clearance of malignant cells by multiple mechanisms, including the formation of immunosuppressive reactive oxygen species (ROS) via the myeloid cell NADPH oxidase (NOX2). Histamine dihydrochloride (HDC), a NOX2 inhibitor, exerts anti-cancer efficacy in experimental tumor models but the detailed mechanisms are insufficiently understood. To determine effects of HDC on the MDSC compartment we utilized three murine cancer models known to entail accumulation of MDSC, i.e. EL-4 lymphoma, MC-38 colorectal carcinoma, and 4T1 mammary carcinoma. In vivo treatment with HDC delayed EL-4 and 4T1 tumor growth and reduced the ROS formation by intratumoral MDSCs. HDC treatment of EL-4 bearing mice also reduced the accumulation of intratumoral MDSCs and reduced MDSC-induced suppression of T cells ex vivo. Experiments using GR1-depleted and Nox2 knock out mice supported that the anti-tumor efficacy of HDC required presence of NOX2(+) GR1(+) cells in vivo. In addition, treatment with HDC enhanced the anti-tumor efficacy of programmed cell death receptor 1 (PD-1) and PD-1 ligand checkpoint blockade in EL-4- and MC-38-bearing mice. Immunomodulatory effects of a HDC-containing regimen on MDSCs were further analyzed in a phase IV trial (Re:Mission Trial, ClinicalTrials.gov; NCT01347996) where patients with acute myeloid leukemia received HDC in conjunction with low-dose IL-2 (HDC/IL-2) for relapse prevention. Peripheral CD14(+)HLA-DR-/low MDSCs (M-MDSCs) were reduced during cycles of HDC/IL-2 therapy and a pronounced reduction of M-MDSCs during HDC/IL-2 treatment heralded favorable clinical outcome. We propose that anti-tumor properties of HDC may comprise the targeting of MDSCs.
|
|
| 2. |
- Kiffin, Roberta, et al.
(författare)
-
Anti-Leukemic Properties of Histamine in Monocytic Leukemia: The Role of NOX2
- 2018
-
Ingår i: Frontiers in Oncology. - : Frontiers Media SA. - 2234-943X. ; 8
-
Tidskriftsartikel (refereegranskat)abstract
- In patients with acute myeloid leukemia (AML), treatment with histamine dihydrochloride (HDC) and low-dose IL-2 (HDC/ IL-2) in the post-chemotherapy phase has been shown to reduce the incidence of leukemic relapse. The clinical benefit of HDC/ IL-2 is pronounced in monocytic forms of AML, where the leukemic cells express histamine type 2 receptors (H2R) and the NAPDH oxidase-2 (NOX2). HDC ligates to H(2)Rs to inhibit NOX2-derived formation of reactive oxygen species, but details regarding the anti-leukemic actions of HDC remain to be elucidated. Here, we report that human NOX2(+) myelomonocytic/monocytic AML cell lines showed increased expression of maturation markers along with reduced leukemic cell proliferation after exposure to HDC in vitro. These effects of HDC were absent in corresponding leukemic cells genetically depleted of NOX2 (NOX2(-/-)). We also observed that exposure to HDC altered the expression of genes involved in differentiation and cell cycle progression in AML cells and that these effects required the presence of NOX2. HDC promoted the differentiation also of primary monocytic, but not non-monocytic, AML cells in vitro. In a xenograft model, immunodeficient NOG mice were inoculated with wild-type or NOX2(-/-) human monocytic AML cells and treated with HDC in vivo. The administration of HDC reduced the in vivo expansion of NOX2(+/+), but not of NOX2(-/-) human monocytic AML cells. We propose that NOX2 may be a conceivable target in the treatment of monocytic AML.
|
|
| 3. |
- Martner, Anna, 1979, et al.
(författare)
-
Histamine Promotes the Development of Monocyte-Derived Dendritic Cells and Reduces Tumor Growth by Targeting the Myeloid NADPH Oxidase
- 2015
-
Ingår i: Journal of Immunology. - : The American Association of Immunologists. - 0022-1767 .- 1550-6606. ; 194:10, s. 5014-5021
-
Tidskriftsartikel (refereegranskat)abstract
- The efficiency of immune-mediated clearance of cancer cells is hampered by immunosuppressive mediators in the malignant microenvironment, including NADPH oxidase-derived reactive oxygen species. We aimed at defining the effects of histamine, an inhibitor of the myeloid NADPH oxidase/NOX2, on the development of Ag-presenting dendritic cells (DCs) from myeloid precursors and the impact of these mechanisms for tumor growth. Histamine was found to promote the maturation of human DCs from monocytes by increasing the expression of HLA-DR and costimulatory molecules, which resulted in improved induction of Th cells with Th0 polarity. Experiments using wild-type and NOX2-deficient myelomonoblastic cells showed that histamine facilitated myeloid cell maturation only in cells capable of generating reactive oxygen species. Treatment of mice with histamine reduced the growth of murine EL-4 lymphomas in parallel with an increment of tumor-infiltrating DCs in NOX2-sufficient mice but not in NOX2-deficient (gp91(phox-/-)) mice. We propose that strategies to target the myeloid NADPH oxidase may facilitate the development of endogenous DCs in cancer.
|
|
| 4. |
- Ortiz, M. L., et al.
(författare)
-
Immature myeloid cells directly contribute to skin tumor development by recruiting IL-17-producing CD4(+) T cells
- 2015
-
Ingår i: Journal of Experimental Medicine. - : Rockefeller University Press. - 0022-1007 .- 1540-9538. ; 212:3, s. 351-367
-
Tidskriftsartikel (refereegranskat)abstract
- Evidence links chronic inflammation with cancer, but cellular mechanisms involved in this process remain unclear. We have demonstrated that in humans, inflammatory conditions that predispose to development of skin and colon tumors are associated with accumulation in tissues of CD33(+)S100A9(+) cells, the phenotype typical for myeloid-derived suppressor cells in cancer or immature myeloid cells (IMCs) in tumor-free hosts. To identify the direct role of these cells in tumor development, we used S100A9 transgenic mice to create the conditions for topical accumulation of these cells in the skin in the absence of infection or tissue damage. These mice demonstrated accumulation of granulocytic IMCs in the skin upon topical application of 12-O-tetradecanoylphorbol-13-acetate (TPA), resulting in a dramatic increase in the formation of papillomas during epidermal carcinogenesis. The effect of IMCs on tumorigenesis was not associated with immune suppression, but with CCL4 (chemokine [C-C motif] ligand 4)-mediated recruitment of IL-17-producing CD4(+) T cells. This chemokine was released by activated IMCs. Elimination of CD4(+) T cells or blockade of CCL4 or IL-17 abrogated the increase in tumor formation caused by myeloid cells. Thus, this study implicates accumulation of IMCs as an initial step in facilitation of tumor formation, followed by the recruitment of CD4(+) T cells.
|
|
