Honors & Awards
AZKK Science Promotion Grant, Astra Zeneca (2013)
Single Cell Gene Expression Analysis Awards, WAT-NeW, TakaraBio and Fluidigm (2014)
Research grant, The Shin-Nihon Foundation of Advanced Medical Research (2018)
Research grant, Fukuoka Foundation for Sound Health Cancer Research Fund (2018)
Grant-in-Aid for Early-Career Scientists, Japan Society for the Promotion of Science (2019)
Paper of the year 2019, Department of Medicine and Biosystemic Science, Kyushu University (2019)
Overseas Research Fellow, Japan Society for the Promotion of Science (2020-2021)
Research Fellowship, The Uehara Memorial Foundation (2022)
School of Medicine Dean's Postdoctoral Fellowship, Stanford University School of Medicine (2022)
Boards, Advisory Committees, Professional Organizations
Board Certified Fellow, Japanese Society of Internal Medicine (2018 - Present)
Board Certified Fellow, Japanese Society of Medical Oncology (2018 - Present)
Ph.D., Kyushu University (2019)
Fellow, Kyushu University/National Kyushu Cancer Center, Oncology (2018)
Residency, Aso Iizuka Hospital (2011)
M.D., Kyushu University (2009)
Current Research and Scholarly Interests
Translation of discoveries in basic cancer research into clinical oncology
RHAMM marks proliferative subpopulation of human colorectal cancer stem cells.
The cancer stem cell (CSC) theory features typically rare self-renewing subpopulation that reconstitute the heterogeneous tumor. Identification of molecules which characterize the feature of CSCs is a key imperative for further understanding of tumor heterogeneity and for the development of novel therapeutic strategies. However, the use of conventional markers of CSCs is still insufficient for the isolation of bona fide CSCs. We investigated organoids which are miniature forms of tumor tissues with reconstructing cellular diversity to identify specific marker to characterize CSCs in heterogeneous tumors. Here, we report that receptor for hyaluronan-mediated motility (RHAMM) expresses in a subpopulation of CD44+ conventional human colorectal CSC fraction. Single-cell transcriptomics of organoids highlighted RHAMM positive proliferative cells that revealed distinct characteristics among the various cell types. Prospectively isolated RHAMM+ CD44+ cells from the human colorectal cancer tissues showed highly proliferative character with self-renewal ability in comparison with the other cancer cells. Furthermore, inhibition of RHAMM strongly suppressed organoids formation in vitro and inhibited the tumor growth in vivo. Our findings suggest that RHAMM is a potential therapeutic target because it is a specific marker of the proliferative subpopulation within the conventional CSC fraction.
View details for DOI 10.1111/cas.15795
View details for PubMedID 36945114
Macrophages are primed to transdifferentiate into fibroblasts in malignant ascites and pleural effusions.
Cancer-associated fibroblasts (CAFs) play an important role in cancer progression. However, the origin of CAFs remains unclear. This study shows that macrophages in malignant ascites and pleural effusions (cavity fluid-associated macrophages: CAMs) transdifferentiate into fibroblast-like cells. CAMs obtained from gastrointestinal cancer patients were sorted by flow cytometry and cultured in vitro. CD45+CD14+ CAMs transdifferentiated into CD45-CD90+ fibroblast-like cells that exhibited spindle shapes. Then, cDNA microarray analysis showed that the CD45-CD90+ fibroblast-like cells (macrophage-derived CAFs: MDCAFs) had a fibroblast-specific gene expression signature and produced growth factors for epithelial cell proliferation. Human colon cancer cells transplanted into immunodeficient mice with MDCAFs formed larger tumors than cancer cells alone. Gene ontology analyses showed the involvement of TGFβ signaling and cell-matrix adhesion in MDCAFs, and transdifferentiation of CAMs into MDCAFs was canceled by inhibiting TGFβ and cell adhesion. Furthermore, the acquired genetic alterations in hematopoietic stem cells (HSCs) were shared in CAMs and MDCAFs. Taken together, CAMs could be a source of CAFs and might originate from HSCs. We propose the transdifferentiation process of CAMs into MDCAFs as a new therapeutic target for fibrosis associated with gastrointestinal cancer.
View details for DOI 10.1016/j.canlet.2022.215597
View details for PubMedID 35150810
Organoid Models of Tumor Immunology.
Trends in immunology
Cellular interactions in the tumor microenvironment (TME) significantly govern cancer progression and drug response. The efficacy of clinical immunotherapies has fostered an exponential interest in the tumor immune microenvironment, which in turn has engendered a pressing need for robust experimental systems modeling patient-specific tumor-immune interactions. Traditional 2D in vitro tumor immunotherapy models have reconstituted immortalized cancer cell lines with immune components, often from peripheral blood. However, newly developed 3D in vitro organoid culture methods now allow the routine culture of primary human tumor biopsies and increasingly incorporate immune components. Here, we present a viewpoint on recent advances, and propose translational applications of tumor organoids for immuno-oncology research, immunotherapy modeling, and precision medicine.
View details for DOI 10.1016/j.it.2020.06.010
View details for PubMedID 32654925
Organoids as Oracles for Precision Medicine in Rectal Cancer.
Cell stem cell
2020; 26 (1): 4-6
Two recent papers in Cell Stem Cell and Nature Medicine (Yao et al.  and Ganesh et al. ) demonstrate the successful use of rectal cancer patient-derived organoids to predict patient responses to neoadjuvant chemoradiation therapy, paving the way toward a new paradigm for precision medicine.
View details for DOI 10.1016/j.stem.2019.12.003
View details for PubMedID 31951587
Dedifferentiation process driven by TGF-beta signaling enhances stem cell properties in human colorectal cancer
2019; 38 (6): 780–93
Cancer stem cells (CSCs) possess the capacity for self-renewal and the potential to differentiate into non-CSCs. The recent discoveries of dynamic equilibrium between CSCs and non-CSCs revealed the significance of acquiring CSC-like properties in non-CSCs as an important process in progression of cancer. The mechanism underlying acquisition of CSC-like properties has mainly been investigated in the context of epithelial-mesenchymal transition. Here, we demonstrate the dedifferentiation process may be an alternative mechanism in acquisition of CSC-like properties in human colorectal cancer cells. By exploring the single-cell gene expression analysis of organoids developed from CD44+ CSCs, we identified TWIST1 as a key molecule for maintaining the undifferentiated state of cancer cells. Consistent with the finding, we found that TGF-beta signaling pathway, a regulator of TWIST1, was specifically activated in the undifferentiated CD44+ CSCs in human colorectal cancer using microarray-based gene expression analysis and quantitative pathology imaging system. Furthermore, we showed that external stimulation with TGF-beta and the induction of TWIST1 converted CD44- non-CSCs into the undifferentiated CD44+ CSCs, leading to the significant increment of CSCs in xenograft models. This study strongly suggests dedifferentiation driven by TGF-beta signaling enhances stem cell properties in human colorectal cancer.
View details for DOI 10.1038/s41388-018-0480-0
View details for Web of Science ID 000458006300002
View details for PubMedID 30181548
Epithelial-mesenchymal transition is activated in CD44-positive malignant ascites tumor cells of gastrointestinal cancer
2018; 109 (11): 3461–70
Disseminated cancer cells in malignant ascites possess unique properties that differ from primary tumors. However, the biological features of ascites tumor cells (ATC) have not been fully investigated. By analyzing ascites fluid from 65 gastrointestinal cancer patients, the distinguishing characteristics of ATC were identified. High frequency of CD44+ cells was observed in ATC using flow cytometry (n = 48). Multiplex quantitative PCR (n = 15) showed higher gene expression of epithelial-mesenchymal transition (EMT)-related genes and transforming growth factor beta (TGF-beta)-related genes in ATC than in the primary tissues. Immunohistochemistry (n = 10) showed that ATC also had much higher expression of phosphorylated SMAD2 than that in the corresponding primary tissues. TGF-beta 1 was detected in all cases of malignant ascites by enzyme-linked immunoassay (n = 38), suggesting the possible interaction of ATC and the ascites microenvironment. In vitro experiments revealed that these ATC properties were maintained by TGF-beta 1 in cultured ATC(n = 3). Here, we showed that ATCrevealed high frequencies of CD44 and possessed distinct EMT features from primary tissues that were mainly maintained by TGF-beta 1 in the ascites.
View details for DOI 10.1111/cas.13777
View details for Web of Science ID 000449711400011
View details for PubMedID 30142697
View details for PubMedCentralID PMC6215886
PD-1+TIM-3+T cells in malignant ascites predict prognosis of gastrointestinal cancer
2018; 109 (9): 2986–92
The liquid biopsy of ascites fluid could be an excellent source of tumor and microenvironment for the study of prognostic biomarkers because of its accessibility. Tumor-infiltrating lymphocytes (TILs) can predict prognosis in multiple malignancies, including the response to immune checkpoint inhibitors, a breakthrough cancer therapy. However, TILs' profiles from malignant ascites have not been extensively studied. Using flow cytometric analysis, we quantified the proportion of exhausted T cells and memory/naive/effector T-cell subsets, among the CD4+ and CD8+ T-cell populations of paired TILs and peripheral blood T cell samples (n = 22). The correlation between CD4+ and CD8+ subset profiles suggested that the combined analysis of CD4+ and CD8+ cells in malignant ascites was clinically significant. We found that cells positive for the exhaustion markers programmed cell death-1 (PD-1), and T-cell immunoglobulin and mucin domain 3 (TIM-3), and cells coexpressing PD-1 and TIM-3 abundantly exist among malignant ascites TILs. Furthermore, patients with high frequency of PD-1+ TIM-3+ cells among the CD4+ and CD8+ T-cell population showed worse clinical outcome in multivariate analysis (n = 27). We propose that exhausted ascites TILs represent a clinically significant prognostic biomarker in advanced gastrointestinal cancer and represent an important target for immune checkpoint inhibitors.
View details for DOI 10.1111/cas.13723
View details for Web of Science ID 000443802900035
View details for PubMedID 30187676
View details for PubMedCentralID PMC6125472
Pemetrexed combined with platinum-based chemotherapy for advanced malignant peritoneal mesothelioma: retrospective analysis of six cases.
2014; 34 (1): 215-20
Malignant peritoneal mesothelioma (PM) is an extremely rare disease. Pemetrexed and platinum have been used for advanced PM following malignant pleural mesothelioma (PLM). Because PM differs considerably from PLM in clinical features, the efficacy and safety of these therapies have yet to be established.Six Japanese patients with PM who had been treated with pemetrexed-based chemotherapy in four Institutions were retrospectively identified. Treatment response, progression-free survival, and overall survival were examined. Toxicities of therapy were also evaluated.Three patients with mild ascites achieved clinical benefits (one with partial response and two with stable disease). Treatments with reduced cisplatin or carboplatin for patients with massive ascites were safely performed. Median PFS and OS were 7.2 and 13.1 months, respectively. Grade 3 hematological toxicities appeared in two patients with massive ascites.Selection of chemotherapy based on the patient's condition, such as ascites, might be important for advanced PM.
View details for PubMedID 24403465
- Complete Remission of Widely Metastatic Human Epidermal Growth Factor Receptor 2-Amplified Pancreatic Adenocarcinoma After Precision Immune and Targeted Therapy With Description of Sequencing and Organoid Correlates. JCO precision oncology 2023; 7: e2100489
Immune organoids: from tumor modeling to precision oncology.
Trends in cancer
Cancer immunotherapies, particularly immune checkpoint inhibitors, are rapidly becoming standard-of-care for many cancers. The ascendance of immune checkpoint inhibitor treatment and limitations in the accurate prediction of clinical response thereof have provided significant impetus to develop preclinical models that can guide therapeutic intervention. Traditional organoid culture methods that exclusively grow tumor epithelium as patient-derived organoids are under investigation as a personalized platform for drug discovery and for predicting clinical efficacy of chemotherapies and targeted agents. Recently, the patient-derived tumor organoid platform has evolved to contain more complex stromal and immune compartments needed to assess immunotherapeutic efficacy. We review the different methodologies for developing a more holistic patient-derived tumor organoid platform and for modeling the native immune tumor microenvironment.
View details for DOI 10.1016/j.trecan.2022.06.001
View details for PubMedID 35773148
An expanded universe of cancer targets.
2021; 184 (5): 1142–55
The characterization of cancer genomes has provided insight into somatically altered genes across tumors, transformed our understanding of cancer biology, and enabled tailoring of therapeutic strategies. However, the function of most cancer alleles remains mysterious, and many cancer features transcend their genomes. Consequently, tumor genomic characterization does not influence therapy for most patients. Approaches to understand the function and circuitry of cancer genes provide complementary approaches to elucidate both oncogene and non-oncogene dependencies. Emerging work indicates that the diversity of therapeutic targets engendered by non-oncogene dependencies is much larger than the list of recurrently mutated genes. Here we describe a framework for this expanded list of cancer targets, providing novel opportunities for clinical translation.
View details for DOI 10.1016/j.cell.2021.02.020
View details for PubMedID 33667368
Activation of central/effector memory T cells and T-helper 1 polarization in malignant melanoma patients treated with anti-programmed death-1 antibody
2018; 109 (10): 3032–42
Human anti-programmed death-1 (PD-1) antibody possesses the capability to revitalize host T cells and has been an effective therapy for metastatic malignant melanoma (MM). The precise subsets of T cells predominantly activated by anti-PD-1, however, have not yet been clarified. In this study, peripheral blood mononuclear cells obtained from MM patients scheduled to receive anti-PD-1 (nivolumab) therapy, and healthy subjects (HS), were systematically examined on flow cytometry to identify changes in the proportion of immune cell subsets. Compared with HS, MM patients prior to therapy had an increased proportion of activated CD8+ T cells with effector memory phenotypes (Tem), and PD-1 positive subsets of CD4+ central memory T cells (Tcm) and T-helper (Th)17 cells. After a single course of anti-PD-1 therapy, MM patients had an increase in activated Tem and Tcm subsets of CD4+ and CD8+ T cells, and activated Th1 plus T-helper follicular 1 cells. There was no consistent change in the proportion of Tfh cells, B cells, natural killer cells, or dendritic cells. The observed activated phenotypes were attenuated during the course of therapy, but regulatory T cells belonging to the CD3+CD4+CD45RO+CD25high fraction increased at disease progression. Taken together, anti-PD-1 therapy modulates systemic immune reactions and exerts anti-tumor effects, not only by revitalizing Tem and Tcm of CD4+ and CD8+ T cells, but also via a shift to a Th1 phenotype.
View details for DOI 10.1111/cas.13758
View details for Web of Science ID 000446319600005
View details for PubMedID 30066977
View details for PubMedCentralID PMC6172076
E-cadherin regulates proliferation of colorectal cancer stem cells through NANOG
2018; 40 (2): 693–703
Cancer stem cells (CSCs) possess a self‑renewal ability and display tumorigenic potential in immunodeficient mice. Colorectal CSCs are thought to be a uniform population and no functionally distinct subpopulations have been identified. Because E‑cadherin is an essential molecule for self‑renewal of embryonic stem cells, we examined E‑cadherin expression, which may play a role in maintaining the properties of CSCs, in EpCAMhigh/CD44+ colorectal CSCs from human primary colorectal cancers. We obtained 18 surgical specimens of human primary colorectal cancer. CD44, EpCAM, and E‑cadherin expression were analyzed by fluorescence‑activated cell sorting. Sorted EpCAMhigh/CD44+ colorectal CSCs were injected into immunodeficient mice to estimate the tumorigenic potential. Genetic profiles were analyzed by cDNA microarray. Notably, colorectal CSCs could be divided into two populations based on the E‑cadherin expression status, and they exhibited different pathological characteristics. Compared to E‑cadherin‑negative colorectal CSCs, E‑cadherin‑positive (EC+) colorectal CSCs demonstrated higher tumor growth potential in vivo. EC+ colorectal CSCs revealed a higher expression of the pluripotency factor NANOG, which contributed to the higher tumor growth potential of EC+ colorectal CSCs through control of cyclin D1 expression. These findings are the first demonstration of functionally distinct subpopulations of colorectal CSCs in human clinical samples.
View details for DOI 10.3892/or.2018.6464
View details for Web of Science ID 000440585500012
View details for PubMedID 29845283
View details for PubMedCentralID PMC6072297
Genome-wide CRISPR-Cas9 Screen Identifies Leukemia-Specific Dependence on a Pre-mRNA Metabolic Pathway Regulated by DCPS
2018; 33 (3): 386-+
To identify novel targets for acute myeloid leukemia (AML) therapy, we performed genome-wide CRISPR-Cas9 screening using AML cell lines, followed by a second screen in vivo. Here, we show that the mRNA decapping enzyme scavenger (DCPS) gene is essential for AML cell survival. The DCPS enzyme interacted with components of pre-mRNA metabolic pathways, including spliceosomes, as revealed by mass spectrometry. RG3039, a DCPS inhibitor originally developed to treat spinal muscular atrophy, exhibited anti-leukemic activity via inducing pre-mRNA mis-splicing. Humans harboring germline biallelic DCPS loss-of-function mutations do not exhibit aberrant hematologic phenotypes, indicating that DCPS is dispensable for human hematopoiesis. Our findings shed light on a pre-mRNA metabolic pathway and identify DCPS as a target for AML therapy.
View details for DOI 10.1016/j.ccell.2018.01.012
View details for Web of Science ID 000427419400008
View details for PubMedID 29478914
View details for PubMedCentralID PMC5849534