Summary In contrast to virtually all other tissues, the anatomy of differentiation in the bone marrow (BM) remains unknown. This is due to a lack of strategies to examine blood cell production in situ, which are required to understand differentiation, lineage commitment decisions, and define how spatial organizing cues inform tissue function. Here we developed approaches to image myelopoiesis and generated atlases of granulocyte and monocyte/dendritic cell differentiation. Granulopoiesis and dendritic/monopoiesis localize to different sinusoids and display lineage-specific spatial and clonal architectures. Acute systemic L. monocytogenes infection induces lineage-specific progenitor clusters through increased progenitor self-renewal, but the different lineages remain spatially separated. Monocyte dendritic cell progenitors (MDP) map with Ly6C lo monocytes and conventional dendritic cells; these localize to a subset of vessels expressing a major regulator of myelopoiesis 1 colony-stimulating-factor 1 (CSF1/ M-CSF). Specific deletion of Csf1 in endothelium disrupted the architecture around MDP and their localization to sinusoids. Subsequently, there were reduced MDP numbers and differentiation ability, and loss of Ly6C lo monocytes and dendritic cells during homeostasis and infection. These data indicate that local cues produced by distinct blood vessels are responsible for specific spatial organization of definitive hematopoiesis.

BackgroundLoss of Amylo-alpha-1-6-glucosidase-4-alpha-glucanotransferase (AGL) drives rapid proliferation of bladder cancer cells by upregulating Hyaluronic acid(HA) Synthase (HAS2) mediated HA synthesis. However the role of HA receptors CD44 and Hyaluronan Mediated Motility Receptor (RHAMM) in regulating the growth of bladder cancer cells driven by loss of AGL has not been studied.MethodsWestern blot analysis and Terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) assay was carried out to study cellular apoptosis with HAS2, CD44 and RHAMM loss in bladder cancer cells with and without AGL expression. Proliferation and softagar assays were carried out to study cellular anchorage dependent and independent growth. Clinicopathologic analysis was carried out on bladder cancer patient datasets.ResultsHigher amounts of cleaved Cas3, Cas9 and PARP was observed in AGL low bladder cancer cell with loss of HAS2, CD44 or RHAMM. TUNEL staining showed more apoptotic cells with loss of HAS2, CD44 or RHAMM in AGL low bladder cancer cells. This revealed that bladder cancer cells whose aggressive growth is mediated by loss of AGL are susceptible to apoptosis with loss of HAS2, CD44 or RHAMM. Interestingly loss of either CD44 or RHAMM induces apoptosis in different low AGL expressing bladder cancer cell lines. Growth assays showed that loss of CD44 and RHAMM predominantly inhibit anchorage dependent and independent growth of AGL low bladder cancer cells. Clinicopathologic analysis revealed that high RHAMM mRNA expression is a marker of poor patient outcome in bladder cancer and patients with high RHAMM and low AGL tumor mRNA expression have poor survival.ConclusionOur findings strongly point to the importance of the HAS2-HA-CD44/RHAMM pathway for rapid growth of bladder cancer cells with loss of AGL and provides rational for targeting this pathway at various steps for “personalized” treatment of bladder cancer patients based of their AGL expression status.Electronic supplementary materialThe online version of this article (doi:10.1186/s12885-016-2756-5) contains supplementary material, which is available to authorized users.

Glycogen debranching enzyme (AGL) and Glycogen phosphorylase (PYG) are responsible for glycogen breakdown. We have earlier shown that AGL is a regulator of bladder tumor growth. Here we investigate the role of AGL in non-small cell lung cancers (NSCLC). Short hairpin RNA (shRNA) driven knockdown of AGL resulted in increased anchorage independent and xenograft growth of NSCLC cells. We further establish that an increase in hyaluronic acid (HA) synthesis driven by Hyaluronic Acid Synthase 2 (HAS2) is critical for anchorage independent growth of NSCLC cells with AGL loss. Using gene knockdown approach against HAS2 and by using 4-methylumbelliferone (4MU), an inhibitor of HA synthesis, we show that HA synthesis is critical for growth of NSCLC cells that have lost AGL. We further show NSCLC cells without AGL expression are dependent on RHAMM for HA signaling and growth. Analysis of NSCLC patient datasets established that patients with low AGL/high HAS2 or low AGL/high RHAMM mRNA expression have poor overall survival compared to patients with high AGL/low HAS2 or high AGL/low RHAMM expression. We show for the first time that loss of AGL promotes anchorage independent growth of NSCLC cells. We further show that HAS2 driven HA synthesis and signaling via RHAMM is critical in regulating growth of these cancer cells with AGL loss. Further patients presenting with low AGL and HAS2 or RHAMM over expressing tumors might present the ideal cohort who would respond to inhibitors of HA synthesis and signaling.