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Matsuo-Takasaki, M.

Publications and source records attributed to Matsuo-Takasaki, M..

4 recordsLinked to original sources

HNRNPC-mediated RNA processing promotes VHL-associated excessive vasculogenesis in von Hippel-Lindau syndrome revealed from patient-derived blood vessel models

Von Hippel-Lindau Syndrome (VHLS) is an inherited disorder characterized by excessive vascularization, which contributes to the development of hemangioblastomas and benign or malignant tumors, as well as renal cell carcinoma (RCC) and cysts in multiple organs. VHLS is caused by mutations in VHL tumor suppressor gene, which encodes a component of an E3 ubiquitin ligase complex. Although therapeutic agents targeting hypoxia-inducible factor 2 alpha (HIF2A), which is stabilized by VHL loss and promotes tumor angiogenesis, have been approved for clinical use, their therapeutic response remains limited in RCC patients associated with VHLS. Therefore, there is an unmet need for the development of alternative therapeutic approaches independent of HIF2A. Here, we establish a human iPSCs-based model of VHLS-associated excessive vasculogenesis using induced pluripotent stem cells (iPSCs) derived from VHLS patients and VHL-edited isogenic iPSC lines. Vascular cells (VCs) differentiated from these VHLS-specific iPSCs exhibited excessive blood vessel formation compared to healthy donor-derived VCs, leading to vascular lesion formation characterized by abundant blood vessels and abnormal cellular growth in vivo. Mechanistically, RNA-binding proteins (RBPs) were preferentially stabilized in the patient-VCs. Among these RBPs, the stabilization of heterogeneous nuclear ribonucleoprotein C1/C2 (HNRNPC), which is a substrate for pVHL-mediated protein degradation independent of HIF2A expression, was critical for the dysregulated vascularization caused by VHL inactivation in this model. These findings provide an iPSCs-derived vascular platform to elucidate VHLS mechanisms and identify HNRNPC as a potential therapeutic target for VHL-driven vascular lesion formations through an HIF2A-independent mechanism.

cell biology↗

Complete suspension culture of human induced pluripotent stem cells supplemented with suppressors of spontaneous differentiation

Human induced pluripotent stem cells (hiPSCs) are promising resources for producing various types of tissues in regenerative medicine; however, the improvement in a scalable culture system that can precisely control the cellular status of hiPSCs is needed. Utilizing suspension culture without microcarriers or special materials allows for massive production, automation, cost-effectiveness, and safety assurance in industrialized regenerative medicine. Here, we found that hiPSCs cultured in suspension conditions with continuous agitation without any microcarriers or extracellular matrix components were more prone to spontaneous differentiation than those cultured in conventional adherent conditions. Adding PKC{beta} and Wnt signaling pathway inhibitors in the suspension conditions suppressed the spontaneous differentiation of hiPSCs into ectoderm and mesendoderm, respectively. In these conditions, we successfully completed the culture processes of hiPSCs including the generation of hiPSCs from peripheral blood mononuclear cells with the expansion of bulk population and single-cell sorted clones, long-term culture with robust self-renewal characteristics, single-cell cloning, direct cryopreservation from suspension culture and their successful recovery, and efficient mass production of a clinical-grade hiPSC line. Our results demonstrate that precise control of the cellular status in suspension culture conditions paves the way for their stable and automated clinical application.

bioengineering↗

Retinoids rescue ceruloplasmin secretion and alleviate oxidative stress in Wilson's disease-specific hepatocytes

Wilsons disease (WD) is a copper metabolic disorder, which is caused by defective ATP7B function. Here, we have generated induced pluripotent stem cells (iPSCs) from WD patients carrying compound heterozygous mutations on ATP7B. ATP7B loss- and gain-of-functions were further manifested with ATP7B-deficient iPSCs and heterozygously-corrected R778L WD patient-derived iPSCs using CRISPR-Cas9-based gene editing. Transcriptome analysis identified abnormalities of retinoid signaling pathway and lipid metabolism in WD-specific hepatocytes. Although the expression level of ATP7B protein was variable among WD-specific hepatocytes, the expression and secretion of ceruloplasmin (Cp), which is a downstream copper carrier in plasma, were consistently decreased. Cp secretion-based drug screening identified all-trans retinoic acid (ATRA) as promising candidates for rescuing Cp secretion. ATRA also alleviated reactive oxygen species (ROS) production induced by lipid accumulation in WD-specific hepatocytes. Our patient-derived iPSC-based hepatic models provide potential therapeutics for liver steatosis in WD and other fatty liver diseases.

cell biology↗

GPR17 is an Essential Component of the Negative Feedback Loop of the Sonic Hedgehog Signalling Pathway in Neural Tube Development

Dorsal-ventral pattern formation of the neural tube is regulated by temporal and spatial activities of extracellular signalling molecules. Sonic hedgehog (Shh) assigns ventral neural subtypes via activation of the Gli transcription factors. Shh activity changes dynamically during neural differentiation, but the mechanisms responsible for regulating this dynamicity are not fully understood. Here we show that the P2Y-type G-protein coupled receptor GPR17 is involved in temporal regulation of the Shh signal. GPR17 was expressed in the ventral progenitor regions of the neural tube and acted as a negative regulator of the Shh signal in chick embryos. While the activation of the GPR17-related signal inhibited ventral identity, perturbation of GPR17 expression led to aberrant expansion of ventral neural domains. Notably, perturbation of GPR17 expression partially inhibited the negative feedback of Gli activity. Moreover, GPR17 increased cAMP activity, suggesting that it exerts its function by inhibiting the processing of Gli3 protein. GPR17 also negatively regulated Shh signalling in neural cells differentiated from mouse embryonic stem cells, suggesting that GPR17 function is conserved among different organisms. Our results demonstrate that GPR17 is a novel negative regulator of Shh signalling in a wide range of cellular contexts.\n\nAuthor SummaryDuring neural development, determination of cell fate and the progress of differentiation are regulated by extracellular signal molecules, including Sonic Hedgehog (Shh). Shh forms a gradient within the embryonic organ of the central nervous system, or the neural tube, and a variety of cells are produced corresponding to the concentration. While the signal concentration is critical for cell fate, recent studies have revealed that the intracellular signal intensity does not always correspond to the Shh concentration. Rather, the intracellular signal intensity changes over time. Importantly, the signal intensity peaks and gradually decreases thereafter, and the half-life of the Shh signal contributes to the cell fate determination. However, the mechanisms for this temporal change are not fully understood.\n\nBy using chick embryos and mouse embryonic stem cells as model systems, we demonstrate that the G-protein coupled receptor, GPR17, is an essential regulator for the negative feedback of the Shh signal during neural development. While GPR17 gene expression is induced by the Shh signal, GPR17 perturbs the Shh signalling pathway. This negative function of GPR17 on the Shh signal is conserved among different vertebrate species. The collective data demonstrate that GPR17 is a negative regulator for the Shh signalling pathway in a wide range of the cellular contexts.

developmental biology↗