title: Discovery of novel INK4C small-molecule inhibitors to promote human and murine hematopoietic stem cell ex vivo expansion.
abstract: Hematopoietic stem cells (HSCs) have emerged as promising therapeutic cell sources for high-risk hematological malignancies and immune disorders. However, their clinical use is limited by the inability to expand these cells ex vivo. Therefore, there is an urgent need to identify specific targets and effective probes that can expand HSCs. Here we report a novel class of INK4C (p18(INK4C) or p18) small molecule inhibitors (p18SMIs), which were initially found by in silico 3D screening. We identified a lead p18 inhibitor, XIE18-6, confirmed its p18-targeting specificity and bioactivity of promoting HSCs expansion, and then performed structure-activity relationship (SAR) studies by synthesizing a series of analogs of XIE18-6. Among these, compound 40 showed the most potent bioactivity in HSCs expansion (ED50 = 5.21 nM). We confirmed that compound 40 promoted expansion of both murine and human HSCs, and also confirmed its p18-targeting specificity. Notably, compound 40 did not show significant cytotoxicity toward 32D cells or HSCs, nor did it augment leukemia cell proliferation. Taken together, our newly discovered p18SMIs represent novel chemical agents for murine and human HSCs ex vivo expansion and also can be used as valuable chemical probes for further HSC biology research towards promising utility for therapeutic purposes.
authors.affiliation: Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy; NIH National Center of Excellence for Computational Drug Abuse Research; Drug Discovery Institute; Departments of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
authors.forename: Xiang-Qun
authors.initials: XQ
authors.lastname: Xie
authors.affiliation: Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy; NIH National Center of Excellence for Computational Drug Abuse Research; Drug Discovery Institute; Departments of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
authors.forename: Peng
authors.initials: P
authors.lastname: Yang
authors.affiliation: Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300020, P. R. China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy; NIH National Center of Excellence for Computational Drug Abuse Research; Drug Discovery Institute; Departments of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.affiliation: Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy; NIH National Center of Excellence for Computational Drug Abuse Research; Drug Discovery Institute; Departments of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
authors.forename: Liping
authors.initials: L
authors.lastname: Wang
authors.affiliation: Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300020, P. R. China.
authors.forename: Yahui
authors.initials: Y
authors.lastname: Ding
authors.affiliation: Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300020, P. R. China.
authors.forename: Ming
authors.initials: M
authors.lastname: Yang
authors.affiliation: Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy; NIH National Center of Excellence for Computational Drug Abuse Research; Drug Discovery Institute; Departments of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
authors.forename: Qin
authors.initials: Q
authors.lastname: Tong
authors.affiliation: Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy; NIH National Center of Excellence for Computational Drug Abuse Research; Drug Discovery Institute; Departments of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
authors.forename: Haizi
authors.initials: H
authors.lastname: Cheng
authors.affiliation: Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300020, P. R. China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Ji
authors.affiliation: Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy; NIH National Center of Excellence for Computational Drug Abuse Research; Drug Discovery Institute; Departments of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
authors.forename: Terence
authors.initials: T
authors.lastname: McGuire
authors.affiliation: Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300020, P. R. China.
authors.forename: Weiping
authors.initials: W
authors.lastname: Yuan
authors.affiliation: Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300020, P. R. China.
authors.forename: Tao
authors.initials: T
authors.lastname: Cheng
authors.affiliation: Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300020, P. R. China.
authors.forename: Yingdai
authors.initials: Y
authors.lastname: Gao
mesh_terms: D000818:Animals; D001665:Binding Sites; D001854:Bone Marrow Cells / Q000166:cytology / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D003374:Coumarins / Q000737:chemistry* / Q000378:metabolism / Q000633:toxicity; D051358:Cyclin-Dependent Kinase 4 / Q000378:metabolism; D051361:Cyclin-Dependent Kinase 6 / Q000378:metabolism; D050763:Cyclin-Dependent Kinase Inhibitor p18 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D062105:Molecular Docking Simulation; D017434:Protein Structure, Tertiary; D054852:Small Molecule Libraries / Q000737:chemistry* / Q000378:metabolism / Q000633:toxicity; D013329:Structure-Activity Relationship; D013425:Sulfanilic Acids / Q000737:chemistry* / Q000378:metabolism / Q000633:toxicity
chemical_list: D003374:Coumarins; D050763:Cyclin-Dependent Kinase Inhibitor p18; D054852:Small Molecule Libraries; D013425:Sulfanilic Acids; C000611987:XIE18-6 compound; D051358:Cyclin-Dependent Kinase 4; D051361:Cyclin-Dependent Kinase 6