Publications by authors named "Akimasa Hayashi"

Pancreatic ductal adenocarcinoma (PDAC) remains a lethal malignancy with poor prognosis. We investigated intratumoral deoxyribonucleic acid methylation heterogeneity by analyzing 44 tumor samples and 5 normal samples from 6 cases of PDAC by using high-resolution methylation arrays. Two distinct methylation profiles were identified: T1, which is similar to normal pancreatic tissue and is associated with well-differentiated histology, and T2, which is significantly different from normal tissue and is linked to poorly differentiated morphology and squamous features.

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Retinochoroidal neovascularization (NV), involved in macular degeneration, diabetic retinopathy, and other ocular diseases, causes vision impairment and blindness. Current treatments rely on repeated intraocular injections of anti-angiogenic drugs, which are burdensome for patients and clinicians, and some patients fail to respond to the treatments. This study investigates the potential of mRNA vaccination to mitigate NV and treat ocular pathologies.

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Inflammatory bowel disease (IBD), comprising ulcerative colitis (UC) and Crohn's disease (CD), is a chronic condition marked by persistent intestinal inflammation of unknown etiology. Disease onset involves genetic predisposition and environmental factors that disrupt the intestinal immune homeostasis. The intestinal microbiome and immune response play pivotal roles in disease progression.

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The manifestation of glioblastoma, IDH-wildtype (GB) as intracranial hemorrhage (ICH) presents diagnostic and therapeutic challenges. Molecular characteristics, including TERT promoter mutation, EGFR amplification, and chromosome 7 gain/10 loss, were incorporated to diagnose GB in the fifth edition of the World Health Organization Classification of Tumors of the Central Nervous System. When molecular analyses fail to detect low fractions of these genetic alterations, the integrated diagnosis of GB can be enigmatic.

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Angiocentric glioma (AG) is a supratentorial diffuse low-grade glioma characterized by the MYB::QKI fusion gene, showing angiocentric growth of monomorphous spindle cells with astrocytic and ependymal immunophenotypes. We describe a rare case of MYB::QKI fusion-positive diffuse cerebellar glioma in a 54-year-old male. The patient initially presented with a T2/FLAIR hyperintense lesion in the left cerebellar hemisphere and slowly progressive neurological symptoms.

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Article Synopsis
  • Scientists studied 91 cases of pancreatic cancer to understand how the DNA changes in these cancers and what that means for patients.
  • They found that having a lot of mutations in the cancer's early development was linked to shorter survival times.
  • Different types of tumors showed varying patterns in how they spread and changed, which means pancreatic cancer can act in more than one way in patients.
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Pancreatic ductal adenocarcinoma (PDAC) is an increasingly diagnosed cancer that kills 90% of afflicted patients, with most patients receiving palliative chemotherapy. We identified neuronal pentraxin 1 (NPTX1) as a cancer-secreted protein that becomes overexpressed in human and murine PDAC cells during metastatic progression and identified adhesion molecule with Ig-like domain 2 (AMIGO2) as its receptor. Molecular, genetic, biochemical, and pharmacologic experiments revealed that secreted NPTX1 acts cell-autonomously on the AMIGO2 receptor to drive PDAC metastatic colonization of the liver-the primary site of PDAC metastasis.

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Article Synopsis
  • Advanced pancreatic ductal adenocarcinoma (PDAC) has different subtypes, with the basal-like subtype showing worse prognosis and chemotherapy resistance compared to the classical subtype.
  • This study evaluated immunohistochemistry (IHC) staining of four markers on biopsy samples from 190 untreated advanced PDAC patients, identifying three distinct patterns: Classical, Transitional, and Basal-like.
  • The Basal-like pattern was linked to poorer survival rates and associated with specific histological features, making IHC expression patterns a valuable tool for predicting prognosis and guiding treatment decisions in advanced PDAC.
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Carrier-free naked mRNA vaccines may reduce the reactogenicity associated with delivery carriers; however, their effectiveness against infectious diseases has been suboptimal. To boost efficacy, we targeted the skin layer rich in antigen-presenting cells (APCs) and utilized a jet injector. The jet injection efficiently introduced naked mRNA into skin cells, including APCs in mice.

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Organ-selective targeting of mRNA polyplexes has been rarely explored despite the substantial potential of polymer-based systems in mRNA delivery. In this study, spleen-selective delivery of polyplexes is achieved by employing mRNA engineering to coat them with poly(ethylene glycol) (PEG). In this approach, mRNA is hybridized with PEGylated complementary RNA oligonucleotides (PEG-OligoRNAs), followed by the addition of linear poly(ethyleneimine).

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Most of esophageal squamous cell carcinoma (ESCC) develop in smoking males in Japan, but the genomic etiology and immunological characteristics of rare non-smoking female ECSS remain unclear. To elucidate the genomic and immunological features of ESCC in non-smoking females, we analyzed whole-genome or transcriptome sequencing data from 94 ESCCs, including 20 rare non-smoking female cases. In addition, 31,611 immune cells were extracted from four ESCC tissues and subject to single-cell RNA-seq.

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Background: Pulmonary inflammatory leiomyosarcoma (PILMS) is a rare type of myogenic tumor with prominent lymphohistiocytic infiltration. Despite their histological similarities, PILMS is immunohistochemically and genetically distinct from soft tissue inflammatory leiomyosarcoma, and its clinicopathological picture including DNA methylome data remains still unknown.

Case Presentation: Here we present a case of PILMS in an 18-year-old male who underwent lobectomy.

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Several types of mucinous lesions of the fallopian tube have been reported, including metaplastic and neoplastic lesions, most of which exhibit gastric phenotypes. Here, we report a unique case of a mucinous tumor arising in the right fallopian tube of a 36-year-old female who presented with refractory abdominal pain for approximately one year. Abdominal CT and MRI found a cystic lesion leading to the diagnosis of hematosalpinx, thus right salpingo-oophorectomy and appendectomy were performed.

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Article Synopsis
  • T cells play a significant role in inflammatory diseases, and this study aimed to better understand the T cell receptor (TCR) repertoires found in various human tissues, especially in relation to graft-versus-host disease (GVHD).
  • Researchers analyzed TCR repertoires in autopsied tissues from patients with and without GVHD, and also in mouse models, finding that similar tissue types had comparable TCR compositions, regardless of disease status.
  • The study revealed that tissue resident T cells, primarily of donor origin, had unique signatures and characteristics that differed from those found in blood, emphasizing the need to focus on tissue analysis for insights into inflammatory conditions.
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Integrating antigen-encoding mRNA (Messenger RNA) and immunostimulatory adjuvant into a single formulation is a promising approach to potentiating the efficacy of mRNA vaccines. Here, we developed a scheme based on RNA engineering to integrate adjuvancy directly into antigen-encoding mRNA strands without hampering the ability to express antigen proteins. Short double-stranded RNA (dsRNA) was designed to target retinoic acid-inducible gene-I (RIG-I), an innate immune receptor, for effective cancer vaccination and then tethered onto the mRNA strand via hybridization.

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Despite insights gained by bulk DNA sequencing of cancer it remains challenging to resolve the admixture of normal and tumor cells, and/or of distinct tumor subclones; high-throughput single-cell DNA sequencing circumvents these and brings cancer genomic studies to higher resolution. However, its application has been limited to liquid tumors or a small batch of solid tumors, mainly because of the lack of a scalable workflow to process solid tumor samples. Here we optimize a highly automated nuclei extraction workflow that achieves fast and reliable targeted single-nucleus DNA library preparation of 38 samples from 16 pancreatic ductal adenocarcinoma patients, with an average library yield per sample of 2867 single nuclei.

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Article Synopsis
  • Hepatoblastoma (HB) is the most common liver cancer in children, but its genetic causes and variations are not fully understood.
  • Researchers studied 163 pediatric liver tumors, finding low levels of somatic mutations that correlate with age, and identified common TERT promoter mutations in older HB cases.
  • DNA methylation analysis revealed that classical HBs have hypomethylated enhancers linked to ASCL2, suggesting that these tumors may originate from immature liver cells with characteristics similar to highly proliferative intestinal cells.
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Background: Adenosquamous carcinoma of the prostate (ASCP) is an extremely rare and aggressive prostate cancer variant, whose genomic characteristics have not been elucidated. Although liquid biopsy of circulating tumor cells (CTCs) is an emerging topic in oncology, no study has assessed CTCs in patients with ASCP.

Case Presentation: A 76-year-old man presented with discomfort in his urethra.

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Pancreatic cancer is a genetic disease, and the recurrent genetic alterations characteristic of pancreatic cancer indicate the cellular processes that are targeted for malignant transformation. In addition to somatic alterations in the most common driver genes (KRAS, CDKN2A, TP53 and SMAD4), large-scale studies have revealed major roles for genetic alterations of the SWI/SNF and COMPASS complexes, copy number alterations in GATA6 and MYC that partially define phenotypes of pancreatic cancer, and the role(s) of polyploidy and chromothripsis as factors contributing to pancreatic cancer biology and progression. Germline variants that increase the risk of pancreatic cancer continue to be discovered along with a greater appreciation of the features of pancreatic cancers with mismatch repair deficiencies and homologous recombination deficiencies that confer sensitivity to therapeutic targeting.

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Ten-eleven translocation 1 (TET1) is an essential methylcytosine dioxygenase of the DNA demethylation pathway. Despite its dysregulation being known to occur in human cancer, the role of TET1 remains poorly understood. In this study, we report that TET1 promotes cell growth in human liver cancer.

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Purpose: Melanoma is a biologically heterogeneous disease composed of distinct clinicopathologic subtypes that frequently resist treatment. To explore the evolution of treatment resistance and metastasis, we used a combination of temporal and multilesional tumor sampling in conjunction with whole-exome sequencing of 110 tumors collected from 7 patients with cutaneous ( = 3), uveal ( = 2), and acral ( = 2) melanoma subtypes.

Experimental Design: Primary tumors, metastases collected longitudinally, and autopsy tissues were interrogated.

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Trimethylation of histone H3 at lysine 27 (H3K27me3) acts as a transcriptional repressor of target genes. Recent immunohistochemical studies have reported a loss of H3K27me3 modification in diffuse (especially 1p/19q-codeleted) gliomas. However, we did not observe H3K27me3 loss in diffuse gliomas using routine immunostaining conditions for the detection of H3K27me3 loss in malignant peripheral nerve sheath tumors (MPNSTs).

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