Crohn's disease (CD) is a chronic and relapsing inflammatory bowel disease affecting the entire gastrointestinal tract. The prevalence of CD among Japanese people is increasing. One of the most frequent complications of CD is perianal fistulas. People living with CD may experience complex perianal fistulas, which can cause intense pain, bleeding, swelling, infection, and anal discharge. Despite medical and surgical advancements, complex perianal fistulas in CD remain challenging for clinicians to treat. CD patients living with perianal fistulas reported a negative impact on many aspects of their quality of life. Darvadstrocel is a cell therapy product containing a suspension of allogeneic expanded adipose-derived mesenchymal stem cells. It has been approved in Europe and Japan for the treatment of complex perianal fistulas that have shown an inadequate response to at least one conventional or biologic therapy in adult patients with non-active/mildly active luminal CD. By exhibiting immunomodulatory and local anti-inflammatory effects at the site of inflammation, it offers a new treatment option for complex perianal fistulas in CD patients. In this manuscript, the characteristic of darvadstrocel, the summary of results from the pivotal phase 3 studies in Europe and Japan, and the development strategy in Japan were introduced.

VEXAS syndrome is a new disease entity characterized by the presence of cytoplasmic vacuoles in blood cells, X-linked autoinflammatory symptoms, and somatic variants in UBA1, which encodes an E1 ubiquitin-activating enzyme. Around 30-50% of VEXAS syndrome patients have concurrent MDS. We and others have recently analyzed clinical and genetic features of MDS associated with VEXAS syndrome and found that most of these cases are categorized in the low-risk subgroup with low bone marrow blast percentages. MDS associated with VEXAS syndrome tended to involve a smaller number of genes and lower-risk genetic alterations than classical MDS. In addition, anemia in MDS associated with VEXAS syndrome with active inflammation before treatment tended to respond well to steroids. In this review, we will present our recent findings together with others, focusing on the new disease entity and pathophysiology of VEXAS syndrome and clinical/genetic features of associated MDS.

The primary cilium, an antenna-like structure of cell membrane, detects various signals and regulates cellular functions such as proliferation and differentiation. The impairment of primary cilium is associated with the etiologies of diseases including cancer, obesity, and congenital anomalies. In this review, novel functions of trichoplein, a suppressor of ciliogenesis, on the regulation of adipose progenitors and fibro-adipogenic progenitors are focused. Trichoplein-knockout mice show resistance to high-fat diet-induced obesity and accelerated regeneration after skeletal muscle injury. The primary cilia of adipose progenitors from trichoplein-knockout mice are elongated, leading to the inhibitions of the accumulation of lipid raft to the base of primary cilia and the phosphorylation of AKT. The primary cilia of fibro-adipogenic progenitors from trichoplein-knockout mice are also elongated, causing the increased expression of IL-13 through IL-33 receptor signaling. These mechanisms are involved in the resistance to diet-induced obesity and improved regeneration. These findings suggest that targeting the primary cilia of specific cells may be a novel therapeutic approach through modulating cellular functions.

The epigenome can adequately regulate the on/off states of genes in response to external environmental factors and stress. In recent years, it has been observed that the epigenome, which is modulated through DNA methylation, histone modifications, and chromatin remodeling, changes with age. Alterations in the epigenome lead to the loss of cell-specific epigenome/identity, which in turn triggers a decline in tissue function. In mammals, postnatal epigenomic variations are not only caused by metabolic diseases, such as diabetes or DNA damage, but also by social stress and infectious diseases. Unlike Genome-Wide Association Studies (GWAS), dynamically changing epigenomes, along with their cellular roles, need to be established as objective biomarkers in conjunction with various biological signals, such as walking speed, brain waves, and clinical data. The biological age/aging clock, determined by methylated DNA, has attracted attention, and calorie restriction not only slows the progression of aging, but also seems to suppress it. However, as indicated by gene expression analysis in aging mice, aging is not a linear model, but is represented by nonlinear dynamic changes. Consequently, the development of experimental models and analytical methods that enhance temporal resolution through time-series analysis, tailored to spatial resolution, such as cell distribution and organ specificity, is progressing. Moreover, in recent years, in addition to anti-aging efforts targeting epigenomic variations, global attention has increasingly focused on research and development aimed at rejuvenating treatments, thus leading to the birth of many biotech companies. Aging Hallmarks such as inflammation, stem cells, metabolism, genomic instability, and autophagy, interact closely with the epigenome. Various postnatal and reversible epigenomic controls of aging, including Yamanaka factors (OKSM and OSK), are now entering a new phase. In the future, the development of aging control using diverse modalities, such as mRNA, artificial peptides, and genome editing, is expected, along with an improved molecular understanding of aging and identification of useful biomarkers.

The transcription factor GATA-1 is essential for erythroid differentiation. Recently, FAM210B, which encodes a mitochondrial inner membrane protein, has been identified as a novel target of GATA-1. To clarify the role of FAM210B, we depleted endogenous FAM210B in human iPS-derived erythroid progenitor (HiDEP-1) cells, and found that erythroid differentiation was more pronounced in the FAM210B depleted cells. Comprehensive metabolite analysis revealed a decline in mitochondrial function accompanied by increased lactate production, indicative of anaerobic glycolysis. Mass spectrometry revealed that FAM210B could interact with multiple subunits of mitochondrial ATP synthases, such as subunit alpha (ATP5A) and beta (ATP5B). Our results suggested that FAM210B contributes prominently to erythroid differentiation by regulating mitochondrial energy metabolism. This review will discuss the potential association between mitochondrial metabolism and erythropoiesis.

A 41-year-old woman with right shoulder pain was found to have multiple tumors with osteolysis and M-proteinemia. Abnormal plasma cells (CD38+, CD138+, Igλ≫κ) were detected in 1.4% of bone marrow nucleated cells, and G-banding analysis revealed a 46,XX,t (8;14), (q24;q32) karyotype in 4 of 20 cells analyzed. A biopsy specimen from an extramedullary lesion had a packed proliferation of aberrant plasmacytoid cells with positive IgH::MYC fusion signals on fluorescence in situ hybridization. The patient was diagnosed with symptomatic multiple myeloma and treated with the BLd regimen, which significantly reduced M protein levels. Extramedullary lesions were initially reduced, but increased again after four cycles. The lesions disappeared with subsequent EPOCH chemotherapy and radiation, and complete remission was confirmed. The patient was then treated with high-dose chemotherapy with autologous peripheral blood stem cell transplantation. Complete remission was maintained for over one year with lenalidomide maintenance therapy. A solitary IgH::MYC chromosomal translocation is extremely rare in multiple myeloma and may be associated with high tumor proliferative capacity, multiple extramedullary lesions, and poor prognosis. Combined therapeutic modalities with novel and conventional chemotherapy and radiation might be a promising treatment strategy for patients with this type of multiple myeloma.

Recent advances in cancer therapy have significantly improved the survival rate of patients with cancer. In contrast, anti-cancer drug-induced adverse effects, especially cardiotoxicity, have come to affect patients' prognosis and quality of life. Therefore, there is a growing need to understand the anti-cancer drug-induced cardiotoxicity. Human induced pluripotent stem (iPS) cell-derived cardiomyocytes (hiPSC-CMs) have been used to assess drug-induced cardiotoxicity by improving the predictability of clinical cardiotoxicity and the principles of the 3Rs (replacement, reduction and refinement). To predict the anti-cancer drug-induced cardiotoxicity, we developed a novel method to assess drug-induced proarrhythmia risk using hiPSC-CMs by participating in the international validation. In addition, we established the chronic contractility toxicity assessment by image-based motion analysis. The compound BMS-986094, which was withdrawn from clinical trials, inhibited contractility velocity and relaxation velocity in hiPSC-CMs. Currently, we are trying to investigate the predictability of the contractility assay by comparing the hiPSC-CM data with adverse events reports from real-world database. In this review, we would like to introduce the novel imaging-based contractility method using hiPSC-CMs and future perspectives in anti-cancer drug-induced cardiotoxicity.

Cardiotoxicity induced by anti-cancer drugs is a significant concern for patients undergoing cancer treatment. Some anti-cancer drugs can damage cardiac muscle cells directly or indirectly, potentially leading to severe heart failure. Various risk factors, including the type and dosage of chemotherapy agents as well as patient background, contribute to the development of cardiotoxicity. Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), which enable patient-specific toxicity prediction, hold great promise in this regard. However, the practical implementation of hiPSC-CMs-based prediction of anti-cancer drug-induced cardiotoxicity still faces hurdles. One major challenge involves establishing and optimizing experimental systems for evaluating contractile dysfunction, the ultimate output of heart failure, using hiPSC-CMs. Such efforts are currently underway globally, focusing on tailoring functional evaluation systems to the characteristics of hiPSC-CMs. In this paper, we provide an overview of the contraction mechanisms of cardiac cells and introduce a method of measuring contraction that we have developed, and discuss the current status of contractile function evaluation methods using hiPSC-CMs.

Cardiotoxicity is a serious adverse effect of anti-cancer drugs. Anti-cancer drug-induced cardiotoxicity are arrhythmia, cardiac contractile dysfunction, coronary artery disease, and hypertension, which affect to the quality of life in patients with cancer. In particular, cardiac contractile dysfunction is a life-threatening symptom leading to heart failure, suggesting that it is very important to predict the risk of developing the contractile dysfunction by anti-cancer drugs. Recently, human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) can be used to assess the risk of drug-induced arrhythmias. This prompts us to evaluate other cardiotoxic effects such as contractility dysfunction and structural toxicity with hiPSC-CMs. Since anti-cancer drug-induced contractility dysfunction are considered to be induced by chronic exposure, we have developed a method to assess chronic contractility dysfunction by imaging analysis of hiPSC-CMs. BMS-986094, which failed in clinical trials due to the occurrence of heart failure, was used as a positive compound. We found that chronic exposure to BMS-986094 decreased the contraction and relaxation velocity in hiPSC-CMs. Doxorubicin was observed to decrease cytotoxicity and both contraction and relaxation velocities in hiPSC-CMs. We are currently further evaluating other anti-cancer drugs with different mode-of-actions using hiPSC-CMs and assess the predictivity and utility of contractile assessment using hiPSC-CMs by comparing with real-world data. Here, we introduce our novel method to assess the chronic contractility of hiPSC-CMs by imaging analysis and discuss the future perspectives for assessing the anti-cancer drug-induced cardiotoxicity.

The patient was a 21-year-old man who had been diagnosed with Crohn's disease and received infliximab and azathioprine six years earlier. He was admitted with fever and fatigue. Peripheral blood examination showed LDH 2,473 U/l and thrombocytopenia, and contrast-enhanced computed tomography (CT) showed hepatosplenomegaly. Bone marrow biopsy and liver biopsy showed CD4+CD56+TCRγδ＋CD8- atypical cells, leading to a diagnosis of hepatosplenic T-cell lymphoma (HSTCL). The patient was refractory to CHOP and DA-EPOCH, and therefore received cord blood transplantation with myeloablative conditioning. CT showed reduced in hepatosplenomegaly and peripheral blood examination showed LDH 165 U/l and plt 180,000/µl, so the patient was discharged on day117. HSTCL is a tumor of immature γδT cells with a Vδ1 mutation in the spleen, and immunodeficiency has been implicated in its pathogenesis. Patients with inflammatory bowel disease treated with azathioprine are known to have an increased risk of lymphoproliferative disease. In this case, use of immunosuppressive drugs for Crohn's disease may have caused malignant transformation of γδ cells in the intestinal epithelium. Although the patient was refractory to chemotherapy, he was able to achieve remission with early cord blood transplantation and long-term survival is expected.

A 64-year-old woman presented with fine motor impairment in both hands. MRI revealed a contrast-enhanced lesion in the medulla oblongata. Lymphoid cells with abnormal blebs were observed and a CD4+/CD8+ double positive (DP) T cell population was detected by flow cytometry (FCM) in the bone marrow (BM) and the peripheral blood (PB). CLEC16A::IL2 fusion gene was identified by whole exome sequencing with DNA prepared from DP T cells. Clonal rearrangement of the T-cell receptor gene and expression of TCL1A protein were detected. This led to a diagnosis of T-cell prolymphocytic leukemia (T-PLL) with central nervous system (CNS) infiltration. Abnormal cells in BM and PB became undetectable on microscopy and FCM, and the CNS lesion disappeared on MRI after second-line therapy with alemtuzumab. Meanwhile, the CLEC16A::IL2 fusion mRNA remained detectable in PB. Allogeneic hematopoietic stem-cell transplantation was performed, and the fusion mRNA has now been undetectable for more than 5 years since transplantation. This is the first report of a T-PLL case with a CLEC16A::IL2 fusion gene.

Aggressive types of adult T-cell leukemia-lymphoma (ATL), namely, the acute type, lymphoma type, and chronic type with poor prognostic factors, have a poor prognosis. Although allogeneic hematopoietic stem cell transplantation (HSCT) may improve prognosis, relapse is common. In June 2021, tucidinostat was approved for relapsed or refractory ATL in Japan. We report a case of a 62-year-old man with relapsed ATL after allogeneic HSCT. In March 2017, he was diagnosed with ATL (acute type) and received two courses of mLSG-15 therapy. ATL cells reappeared in his peripheral blood, so he underwent allogeneic bone marrow transplantation in September 2017. In June 2021, his soluble interleukin-2 receptor (sIL-2R) level increased, and he began experiencing sensory abnormalities in his face and legs. In September, he developed respiratory failure and was diagnosed with relapse of ATL. He was again treated with mLSG-15. His sIL-2R normalized and the sensory abnormalities decreased, but sIL-2R rose again in February 2022. After tucidinostat treatment was initiated, sIL-2R normalized and the patient's general condition improved. Tucidinostat shows promise as an effective treatment for ATL that has relapsed after allogeneic HSCT.

Although miR-29b levels in peritoneal exosomes was markedly reduced in patients with peritoneal metastases(PM), their role has not been fully clarified. Bone marrow derived mesenchymal stem cells(BMSC)were transfected with miR-29b- integrating lentivirus and exosomes isolated from culture supernatants using ultracentrifugation. The effects of the exosomes on human peritoneal mesothelial cells(HPMC)were examined in vitro. The in vivo effect of murine BMSC-derived exosomes was examined with a syngeneic PM model. Culture of HPMC with TGF-β1 decreased expression of E-cadherin and calretinin with increased expression of vimentin, totally restored by adding miR-29b-rich exosomes. The exosomes inhibited proliferation and migration of HPMC, and inhibited adhesion of gastric cancer cells to HPMC. Intraperitoneal(IP)transfer of miR- 29b-rich exosomes every 3 days markedly reduced the number of PM of a murine gastric cancer cell, YTN16P, on the mesentery of C57/BL6 mice. IP administration of miR-29b-containing exosome suppresses the development of PM of gastric cancer.

Persister cells constitute a subset of cancer cells that exhibit resistance to anticancer therapies. They evade anticancer drug-induced cell death by slowing down the cell cycle and transiently adapting to the drugs through multiple pathways. Subsequently, these persister cells function as reservoirs, leading cancer cells towards diverse and irreversible mechanisms of drug resistance. The causes of treatment resistance in persister cells have been reported to be primarily epigenetic changes, rather than irreversible genetic mutations. Acquisition of stem-like features, epithelial-to-mesenchymal transition, alterations in survival and apoptosis signaling, changes in metabolism, variations in the tumor microenvironment, and acquisition of immune escape mechanisms are reported to be involved in the survival of persister cells. Although various therapeutic interventions have been explored for each of these aspects, few have been clinically applied. In this article, we place a particular emphasis on EGFR lung cancer and persister cells. We discuss the reasons why EGFR tyrosine kinase inhibitors fail to achieve curative outcomes and consider the biological characteristics of persister cells. We also review an overview of potential therapeutic strategies to overcome persister cell-induced resistance.

Adenosine-5'-triphosphate (ATP) is an important intracellular energy currency, but it is released extracellularly in response to various stimuli and acts as an intercellular signaling molecule by stimulating various P2 receptors. ATP and ADP are stored in synaptic vesicles and secretory granules, and are released extracellularly upon stimulation, playing important roles in neurotransmission and platelet aggregation. Furthermore, considerable amount of ATP is released by mechanical stimuli such as skin scraping or by cell damage, which in turn activates immune cells to promote inflammatory responses. Mast cells (MCs) are derived from hematopoietic stem cells and play a central role in type I allergic reactions. MCs are activated by IgE-mediated antigen recognition, leading to type I allergic reactions. MCs express P2X7 receptors that are activated by high concentrations of ATP (>0.5 ‍mM), and reported to aggravate inflammatory bowel disease and dermatitis. In contrast, role of MC P2 receptors that respond to lower concentrations of ATP remains to be investigated. We investigated in detail the effects of ATP in mouse bone marrow-derived MCs, and found that lower concentrations of ATP (<100 ‍μM) promotes IgE-dependent and GPCR-mediated degranulation via the ionotropic P2X4 receptor. In mouse allergic models, P2X4 receptor signal promote MC-mediated allergic responses through comprehensively increasing the sensitivity of MCs to different stimuli. Since ATP is known to be released from various cells upon mechanical stimuli such as cell damage or scratching, inhibition of P2X4 receptor signaling may represent a novel strategy to abrogate allergic reaction.

Sulfur- or nitrogen-containing compounds from medicinal plants exhibit various biological activities such as anticancer potential. Developing efficient strategies to isolate or synthesize these compounds or their derivatives is a remarkable achievement. We have isolated several sulfur-containing compounds such as tetrahydro-2H-difuro[3,2-b:2',3'-c]furan-5(5aH)-one derivatives from Allium plants. We have devised a unique approach for the rapid preparation of thiopyranones using the regioselective sequential double Diels-Alder reaction; we used a naturally-occurring chemically-unstable intermediate such as thioacrolein, which is produced from allicin, a major component in garlic. The cytotoxicity of the synthetic thiopyranones against cancer stem cells (CSCs) was equal to or higher than that of (Z)-ajoene, the reference compound.

We report the case of a 65-year-old man who was diagnosed with Bickerstaff brainstem encephalitis prior to central nervous system (CNS) relapse of diffuse large B-cell lymphoma (DLBCL). He was diagnosed with DLBCL of the paranasal sinus in June 2022. After treatment with 6 cycles of R-GCVP (rituximab, gemcitabine, cyclophosphamide, vincristine, prednisolone) and 2 cycles of high-dose methotrexate (HD-MTX), complete remission was confirmed. In June 2023, the patient developed dizziness and was admitted to our hospital. MRI showed FLAIR high-intensity areas extending from the medial part of each thalamus to the pons. Cerebrospinal fluid (CSF) showed increased mononuclear cells, but they were predominantly T-cells. Impairment of consciousness progressed, and thus the patient was treated with HD-MTX based on a presumptive diagnosis of CNS relapse of DLBCL. However, there was no improvement. An anti-GQ1b IgG antibody test was positive, leading to a diagnosis of Bickerstaff encephalitis, and 6 sessions of plasma exchange were performed. Neurological symptoms improved after these treatments, but 2 months later, the left blepharoptosis and ophthalmoparesis reappeared. CSF analysis revealed B-cell clonality, and the patient was diagnosed with CNS relapse. Autoimmune encephalitis should be considered as a differential diagnosis even in patients with lymphoma who are at high risk of CNS invasion.

B-cell non-Hodgkin's lymphoma is a very heterogonous malignancy with diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL) as the most common subtypes. Recent advances in chimeric antigen receptor T-cell (CAR-T) therapy are changing the current landscape for management of relapsed or refractory (R/R) DLBCL and R/R FL, which have a poor prognosis. Pivotal trials leading to the FDA approval of three CD19 CAR-T cells (Yescarta®, Kymriah® and Breyanzi®) showed complete response (CR) rates of 40-60%, with a significant subset of patients achieving long-term disease remission. Real-world studies have also confirmed this data. Notable toxicities include cytokine release syndrome and neurologic toxicities, which are usually treatable and reversible, as well as cytopenias and hypogammaglobulinemia. Salvage chemoimmunotherapy followed by high-dose chemotherapy and autologous stem cell rescue is the standard of care for chemo-sensitive and transplant-eligible R/R DLBCL. This review highlights the approved CAR-T constructs, including their efficacy, adverse effects, and real-world data.

Most drugs are metabolized and detoxified in the liver. Therefore, human hepatocytes are essential for pharmacokinetic and toxicity tests in pharmaceutical research. Although primary human hepatocytes (PHHs) are the main cell source used as a human liver model, major drawbacks include the limited supply of PHHs and their functional deterioration due to long-term culture. Many studies have been conducted to overcome these problems or develop new hepatocyte sources. In particular, stem cells with cell proliferative potential are expected to be useful in pharmaceutical research, as they can supply many homogeneous specific somatic cells through differentiation and maturation. Here, we describe recent advances in the use of hepatocyte-like cells derived from human embryonic stem (ES) cells or induced pluripotent stem (iPS) cells and human liver organoids. The hepatocyte differentiation method from human ES/iPS cells by some strategies has been improved. However, the hepatic functions in human hepatocyte-like cells derived from ES/iPS cells are still lower than those in PHHs. Similarly, although human liver organoids show long-term proliferation, their hepatic functions remain low. Human ES/iPS cells and liver organoids could overcome the limited supply of PHHs, but improving their hepatic function is essential. We believe that stem cell culture technology will be useful for generating a functional hepatocyte source for medical applications.