Makoto Yamagishi

The EZH2-mediated epigenome and subsequent transcriptome define cellular identity. Effective and specific strategies for the manipulation of EZH2/PRC2 may lead to the development of more precise cancer medicines.

Subclonal genetic heterogeneity and their diverse gene expression impose serious problems in understanding the behavior of cancers and contemplating therapeutic strategies. Here we develop and utilize a capture-based sequencing panel, which covers host hotspot genes and the full-length genome of human T-cell leukemia virus type-1 (HTLV-1), to investigate the clonal architecture of adult T-cell leukemia-lymphoma (ATL). For chronologically collected specimens from patients with ATL or pre-onset in

The molecular hallmarks of adult T cell leukemia (ATL) comprise outstanding deregulations of signaling pathways that control the cell cycle, resistance to apoptosis, and proliferation of leukemic cells, all of which have been identified by early excellent studies. Nevertheless, we are now confronted the therapeutic difficulties of ATL that is a most aggressive T cell leukemia/lymphoma. Using next-generation strategies, emerging molecular characteristics such as specific surface markers and an ad

Biological robustness is exposed to stochastic perturbations, which should be controlled by intrinsic mechanisms; the promiscuous signaling network without appropriate alleviation is the true nature of cancer cells. B cell receptor (BCR) signaling is a major source of gene expression signature important for B cell. It is still unclear the mechanism by which the expression of functionally important genes is continuously deregulated in malignant lymphomas. Using RISC-capture assay, we reveal that

T cells infected with human T-cell leukemia virus type 1 (HTLV-1) acquire various abnormalities during a long latent period and transform into highly malignant adult T-cell leukemia-lymphoma (ATL) cells. This can be described as "clonal evolution", in which a single clone evolves into ATL cells after overcoming various selective pressures in the body of the infected individuals. Many studies have shown that the genome and epigenome contain a variety of abnormalities, which are reflected in gene

Abstract Epigenetic program is a molecular basis of cellular identity and functions. We have shown the transcriptome (Cancer Cell, 2012) and the underlying histone methylation patterns (Blood, 2016) of adult T-cell leukemia-lymphoma (ATL). The epigenetic landscape of ATL is defined as "genome-wide H3K27me3 accumulation". Similar accumulation has been detected in multiple cancers, particularly in hematological malignancies. Relief of the cumulative methylation may restore the aberrant transcripto

Malignant lymphomas are a group of diseases with epigenomic abnormalities fundamental to pathogenesis and pathophysiology. They are characterized by a high frequency of abnormalities related to DNA methylation regulators (DNMT3A, TET2, IDH2, etc.) and histone modifiers (EZH2, HDAC, KMT2D/MLL2, CREBBP, EP300, etc.). These epigenomic abnormalities directly amplify malignant clones. They also originate from a hematopoietic stem cell-derived cell lineage triggered by epigenomic changes. These charac

Although human T cell leukemia virus type I (HTLV-I) is undoubtedly involved in the immortalization and leukemogenesis of infected cells, mechanistic underpinnings of its molecular pathophysiology in long latent period of Adult T-cell leukemia (ATL) remain to be elucidated. One of the most significant recent advances in biomedical research has been the discovery of small noncoding RNAs designated microRNA (miRNA), which affect the field of virology including HTLV-1 research. Mounting evidence in

Abstract Adult T-cell leukemia/lymphoma (ATL) is an aggressive T cell leukemia/lymphoma and is refractory to currently available combination chemotherapy. The unfavorable prognosis results from an inadequate understanding of how diseases are caused and maintained in human T-cell leukemia virus type I (HTLV-1)-infected individuals. To date, direct comprehensive analyses of leukemic cells have identified the intrinsic molecular hallmarks of ATL. Among these, polycomb group (PcG)-mediated epigeneti

The molecular hallmarks of ATL comprise outstanding deregulations of signaling pathways that control cell cycle, apoptosis resistance, and proliferation of leukemic cells. Using integrative analyses of primary ATL cells, we discovered unique molecular characteristics of ATL (Yamagishi et al., Cancer Cell, 2012). Genetic and epigenetic disruption leads to numerous gene expression alterations that dominate disorders of homeostasis and characteristics of ATL. In particular, a novel tumor suppressor

Although crucial roles of microRNA have begun to emerge, detailed studies with ATL patients have not been achieved. Using 40 primary ATL samples and 22 samples of normal CD4+ T-cells, we determined the microRNA signatures of ATL and revealed loss of miR-31, which has recently been reported as a metastasis-associated miRNA. All ATL cases invariably showed undetectable or very low levels of miR-31, clearly implying that miR-31 loss is involved in ATL development. As a novel miR-31 target gene,

Histone H3 lysine 27 tri-methylation (H3K27me3) -dependent transcription regulation is a fundamental process of gene control. Although EZH2 mutation is observed in certain lymphoma types, many other cancers show global H3K27me3 accumulation irrespective of mutation. However, the underlying mechanisms of gene silencing and therapeutic efficacies of epigenetic drugs remain unclear. In this study, we showed that globally-accumulated H3K27me3 is induced by both cis-bound EZH1 and EZH2 in mature lymp