title: RepSox slows decay of CD34+ acute myeloid leukemia cells and decreases T cell immunoglobulin mucin-3 expression.
abstract: Despite initial response to therapy, most acute myeloid leukemia (AML) patients relapse. To eliminate relapse-causing leukemic stem/progenitor cells (LPCs), patient-specific immune therapies may be required. In vitro cellular engineering may require increasing the "stemness" or immunogenicity of tumor cells and activating or restoring cancer-impaired immune-effector and antigen-presenting cells. Leukapheresis samples provide the cells needed to engineer therapies: LPCs to be targeted, normal hematopoietic stem cells to be spared, and cancer-impaired immune cells to be repaired and activated. This study sought to advance development of LPC-targeted therapies by exploring nongenetic ways to slow the decay and to increase the immunogenicity of primary CD34(+) AML cells. CD34(+) AML cells generally displayed more colony-forming and aldehyde dehydrogenase activity than CD34(-) AML cells. Along with exposure to bone marrow stromal cells and low (1%-5%) oxygen, culture with RepSox (a reprogramming tool and inhibitor of transforming growth factor-β receptor 1) consistently slowed decline of CD34(+) AML and myelodysplastic syndrome (MDS) cells. RepSox-treated AML cells displayed higher CD34, CXCL12, and MYC mRNA levels than dimethyl sulfoxide-treated controls. RepSox also accelerated loss of T cell immunoglobulin mucin-3 (Tim-3), an immune checkpoint receptor that impairs antitumor immunity, from the surface of AML and MDS cells. Our results suggest RepSox may reduce Tim-3 expression by inhibiting transforming growth factor-β signaling and slow decay of CD34(+) AML cells by increasing CXCL12 and MYC, two factors that inhibit AML cell differentiation. By prolonging survival of CD34(+) AML cells and reducing Tim-3, RepSox may promote in vitro immune cell activation and advance development of LPC-targeted therapies.
authors.affiliation: Alexander B. Osborn Hematopoietic Malignancy and Transplantation Program of the Mary Babb Randolph Cancer Center, Cancer Cell Biology Program, and Departments of Pathology, Neurobiology and Anatomy, and Microbiology, Immunology and Cell Biology, Robert C. Byrd Health Sciences Center, West Virginia University School of Medicine, Morgantown, West Virginia, USA.
authors.forename: Audrey N
authors.initials: AN
authors.lastname: Jajosky
authors.affiliation: Alexander B. Osborn Hematopoietic Malignancy and Transplantation Program of the Mary Babb Randolph Cancer Center, Cancer Cell Biology Program, and Departments of Pathology, Neurobiology and Anatomy, and Microbiology, Immunology and Cell Biology, Robert C. Byrd Health Sciences Center, West Virginia University School of Medicine, Morgantown, West Virginia, USA.
authors.forename: James E
authors.initials: JE
authors.lastname: Coad
authors.affiliation: Alexander B. Osborn Hematopoietic Malignancy and Transplantation Program of the Mary Babb Randolph Cancer Center, Cancer Cell Biology Program, and Departments of Pathology, Neurobiology and Anatomy, and Microbiology, Immunology and Cell Biology, Robert C. Byrd Health Sciences Center, West Virginia University School of Medicine, Morgantown, West Virginia, USA.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Vos
authors.affiliation: Alexander B. Osborn Hematopoietic Malignancy and Transplantation Program of the Mary Babb Randolph Cancer Center, Cancer Cell Biology Program, and Departments of Pathology, Neurobiology and Anatomy, and Microbiology, Immunology and Cell Biology, Robert C. Byrd Health Sciences Center, West Virginia University School of Medicine, Morgantown, West Virginia, USA.
authors.forename: Karen H
authors.initials: KH
authors.lastname: Martin
authors.affiliation: Alexander B. Osborn Hematopoietic Malignancy and Transplantation Program of the Mary Babb Randolph Cancer Center, Cancer Cell Biology Program, and Departments of Pathology, Neurobiology and Anatomy, and Microbiology, Immunology and Cell Biology, Robert C. Byrd Health Sciences Center, West Virginia University School of Medicine, Morgantown, West Virginia, USA.
authors.forename: Jamie R
authors.initials: JR
authors.lastname: Senft
authors.affiliation: Alexander B. Osborn Hematopoietic Malignancy and Transplantation Program of the Mary Babb Randolph Cancer Center, Cancer Cell Biology Program, and Departments of Pathology, Neurobiology and Anatomy, and Microbiology, Immunology and Cell Biology, Robert C. Byrd Health Sciences Center, West Virginia University School of Medicine, Morgantown, West Virginia, USA.
authors.forename: Sharon L
authors.initials: SL
authors.lastname: Wenger
authors.affiliation: Alexander B. Osborn Hematopoietic Malignancy and Transplantation Program of the Mary Babb Randolph Cancer Center, Cancer Cell Biology Program, and Departments of Pathology, Neurobiology and Anatomy, and Microbiology, Immunology and Cell Biology, Robert C. Byrd Health Sciences Center, West Virginia University School of Medicine, Morgantown, West Virginia, USA lgibson@hsc.wvu.edu.
authors.forename: Laura F
authors.initials: LF
authors.lastname: Gibson
mesh_terms: D000444:Aldehyde Dehydrogenase / Q000378:metabolism; D018952:Antigens, CD34 / Q000235:genetics / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D065150:Cellular Reprogramming / Q000187:drug effects*; D054377:Chemokine CXCL12 / Q000235:genetics / Q000378:metabolism; D018920:Coculture Techniques; D004305:Dose-Response Relationship, Drug; D061252:Feeder Cells; D015973:Gene Expression Regulation, Leukemic / Q000187:drug effects; D000072597:Hepatitis A Virus Cellular Receptor 2; D006801:Humans; D007937:Leukapheresis; D015470:Leukemia, Myeloid, Acute / Q000235:genetics / Q000276:immunology / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D014411:Neoplastic Stem Cells / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D010100:Oxygen / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics / Q000378:metabolism; D011720:Pyrazoles / Q000494:pharmacology*; D011725:Pyridines / Q000494:pharmacology*; D000077293:Receptor, Transforming Growth Factor-beta Type I; D018125:Receptors, Transforming Growth Factor beta / Q000037:antagonists & inhibitors / Q000378:metabolism; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D013997:Time Factors; D014407:Tumor Cells, Cultured; D019139:Tumor Escape
chemical_list: D018952:Antigens, CD34; D014408:Biomarkers, Tumor; C515255:CXCL12 protein, human; D054377:Chemokine CXCL12; C448908:HAVCR2 protein, human; D000072597:Hepatitis A Virus Cellular Receptor 2; C489427:MYC protein, human; D008565:Membrane Proteins; D016271:Proto-Oncogene Proteins c-myc; D011720:Pyrazoles; D011725:Pyridines; D018125:Receptors, Transforming Growth Factor beta; C550621:RepSox; D000444:Aldehyde Dehydrogenase; D017346:Protein Serine-Threonine Kinases; D000077293:Receptor, Transforming Growth Factor-beta Type I; D010100:Oxygen
keywords: Acute myeloid leukemia; CD34+; Cancer stem cells; Immunogenicity; Immunotherapy; Tim-3