bims-stacyt 2019-10-06 papers

Immunol Lett. 2019 Sep 27. pii: S0165-2478(19)30340-2. [Epub ahead of print]

Hypoxia enhances IL-10-producing B cell generation through upregulating high-mobility group B1 on tumor cell-released autophagosomes.

Yue Zhang, Ning Pan, Yemeng Sheng, Meng Zhou, Zhifa Wen, Yongqiang Chen, Fang Huang, Li-Xin Wang.

As common features of human solid tumors, hypoxia and nutrient starvation play multifaceted roles in cancer progress. However, the mechanisms are far from clear. Our previous work has indicated that tumor cell-released autophagosomes (TRAPs) are sufficient to suppress anti-tumor immune response in mouse by inducing IL-10-producing B cells through high-mobility group B1 (HMGB1). Here, we hypothesized that hypoxia or starvation might exert immunosuppressive effect through upregulating HMGB1 on TRAPs. We found that HMGB1 on TRAPs from human hepatocellular carcinoma cell line HepG2 played a significant role in IL-10-producing B cell induction. HMGB1 in tumor cells was upregulated under hypoxia and starvation, but only hypoxia significantly enhanced the level of HMGB1 present on the surfaces of TRAPs. Moreover, hypoxic TRAPs induced more IL-10-producing B cells with suppressive activities on CD4+ and CD8+ T cells. The finding indicates the role of TRAPs as a messenger of hypoxic response to enhance immunosuppression in tumor microenvironment.

Keywords: B cells; High-mobility group B1 (HMGB1); Hypoxia; IL-10; Tumor cell-released autophagosomes (TRAPs)

DOI: https://doi.org/10.1016/j.imlet.2019.09.005

Cancer Res. 2019 Oct 04. pii: canres.2994.2018. [Epub ahead of print]

Absence of HIF1A leads to glycogen accumulation and an inflammatory response that enables pancreatic tumor growth.

Marco Maruggi, Fabiana I A L Layng, Robert Lemos, Guillermina Garcia, Brian P James, Monica Sevilla, Ferran Soldevila, Bas J G Baaten, Petrus R de Jong, Mei Yee Koh, Garth Powis.

Cancer cells respond to hypoxia by upregulating the hypoxia-inducible factor 1α HIF1A) transcription factor, which drives survival mechanisms that include metabolic adaptation and induction of angiogenesis by vascular endothelial growth factor (VEGF). Pancreatic tumors are poorly vascularized and severely hypoxic. To study the angiogenic role of HIF1A, and specifically probe whether tumors are able to use alternative pathways in its absence, we created a xenograft mouse tumor model of pancreatic cancer lacking HIF1A. After an initial delay of about 30 days the HIF1A-deficient tumors grew as rapidly as the wild type tumors and had similar vascularization. These changes were maintained in subsequent passages of tumor xenografts in vivo and in cell lines ex vivo. There were many cancer cells with a "clear cell" phenotype in the HIF1A-deficient tumors; this was the result of accumulation of glycogen. Single-cell RNA sequencing (scRNAseq) of the tumors identified hypoxic cancer cells with inhibited glycogen breakdown which promoted glycogen accumulation, and the secretion of inflammatory cytokines including interleukins 1β (IL-1B) and 8 (IL-8). scRNAseq of the mouse tumor stroma showed enrichment of 2 subsets of myeloid dendritic cells (cDC), cDC1 and cDC2, that secreted pro-angiogenic cytokines. These results suggest that glycogen accumulation associated with a clear cell phenotype in hypoxic cancer cells lacking HIF1A can initiate an alternate pathway of cytokine and DC-driven angiogenesis. Inhibiting glycogen accumulation may provide a treatment for cancers with the clear cell phenotype.

DOI: https://doi.org/10.1158/0008-5472.CAN-18-2994

FASEB J. 2019 Oct 01. fj201900232RR

Broad-spectrum chemokine inhibition blocks inflammation-induced angiogenesis, but preserves ischemia-driven angiogenesis.

Dhanya Ravindran, Siân P Cartland, Christina A Bursill, Mary M Kavurma.

M3 is a broad-spectrum chemokine-binding protein that inactivates inflammatory chemokines, including CCL2, CCL5, and CX3CL1. The aim of this study was to compare whether M3 could inhibit angiogenesis driven by inflammation or ischemia. Here, apolipoprotein E-/- mice were injected with adenoviral M3 (AdM3) or control adenoviral green fluorescent protein (AdGFP) 3 d prior to stimulating angiogenesis using 2 established models that distinctly represent inflammatory or ischemia-driven angiogenesis, namely the periarterial femoral cuff and hind limb ischemia. AdM3 reduced intimal thickening, adventitial capillary density, and macrophage accumulation in femoral arteries 21 d after periarterial femoral cuff placement compared with AdGFP-treated mice (P < 0.05). AdM3 also reduced mRNA expression of proangiogenic VEGF, inflammatory markers IL-6 and IL-1β, and vascular smooth muscle cell (VSMC)-activated synthetic markers Krüppel-like family of transcription factor 4 (KLF4) and platelet-derived growth factor receptor β (PDGFRβ) in the inflammatory cuff model. In contrast, capillary density, VSMC content, blood flow perfusion, and VEGF gene expression were unaltered between groups in skeletal muscle following hind limb ischemia. In vitro, AdM3 significantly reduced human microvascular endothelial cell 1 proliferation, migration, and tubule formation by ∼17, 71.3, and 8.7% (P < 0.05) in macrophage-conditioned medium associating with reduced VEGF and hypoxia-inducible factor 1α mRNA but not in hypoxia (1% O2). Compared with AdGFP, AdM3 also inhibited VSMC proliferation and migration and reduced mRNA expression of KLF4 and PDGFRβ under inflammatory conditions. In contrast, AdM3 had no effect on VSMC processes in response to hypoxia in vitro. Our findings show that broad-spectrum inhibition of inflammatory chemokines by M3 inhibits inflammatory-driven but not ischemia-driven angiogenesis, presenting a novel strategy for the treatment of diseases associated with inflammatory-driven angiogenesis.-Ravindran, D., Cartland, S. P., Bursill, C. A., Kavurma, M. M. Broad-spectrum chemokine inhibition blocks inflammation-induced angiogenesis, but preserves ischemia-driven angiogenesis.

Keywords: M3; blood vessel remodeling; chemokine blockade

DOI: https://doi.org/10.1096/fj.201900232RR

Sci Rep. 2019 Oct 03. 9(1): 14248

ADP-dependent glucokinase regulates energy metabolism via ER-localized glucose sensing.

Roland Imle, Bei-Tzu Wang, Nicolas Stützenberger, Jana Birkenhagen, Amol Tandon, Matthias Carl, Nastassja Himmelreich, Christian Thiel, Hermann-Josef Gröne, Gernot Poschet, Mirko Völkers, Karsten Gülow, Anne Schröder, Sara Carillo, Stefan Mittermayr, Jonathan Bones, Marcin Mikołaj Kamiński, Stefan Kölker, Sven Wolfgang Sauer.

Modulation of energy metabolism to a highly glycolytic phenotype, i.e. Warburg effect, is a common phenotype of cancer and activated immune cells allowing increased biomass-production for proliferation and cell division. Endoplasmic reticulum (ER)-localized ADP-dependent glucokinase (ADPGK) has been shown to play a critical role in T cell receptor activation-induced remodeling of energy metabolism, however the underlying mechanisms remain unclear. Therefore, we established and characterized in vitro and in vivo models for ADPGK-deficiency using Jurkat T cells and zebrafish. Upon activation, ADPGK knockout Jurkat T cells displayed increased cell death and ER stress. The increase in cell death resulted from a metabolic catastrophe and knockout cells displayed severely disturbed energy metabolism hindering induction of Warburg phenotype. ADPGK knockdown in zebrafish embryos led to short, dorsalized body axis induced by elevated apoptosis. ADPGK hypomorphic zebrafish further displayed dysfunctional glucose metabolism. In both model systems loss of ADPGK function led to defective N- and O-glycosylation. Overall, our data illustrate that ADPGK is part of a glucose sensing system in the ER modulating metabolism via regulation of N- and O-glycosylation.

DOI: https://doi.org/10.1038/s41598-019-50566-6