Defined, serum/feeder-free conditions for expansion and drug screening of primary B-acute lymphoblastic leukemia

// Zhiwu Jiang 1, 2, 3 , Di Wu 1, 2 , Wei Ye 1, 2 , Jianyu Weng 4 , Peilong Lai 4 , Pengcheng Shi 5 , Xutao Guo 5 , Guohua Huang 6 , Qiuhua Deng 6 , Yanlai Tang 7 , Hongyu Zhao 8 , Shuzhong Cui 9 , Simiao Lin 1, 2 , Suna Wang 1, 2 , Baiheng Li 1, 2 , Qiting Wu 1, 2 , Yangqiu Li 10 , Pentao Liu 11 , Duanqing Pei 1, 2 , Xin Du 4 , Yao Yao 1, 2, 3 and Peng Li 1, 2, 3 1 Key Laboratory of Regenerative Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China 2 Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China 3 Department of Abdominal Surgery, Affiliated Cancer Hospital and Institute of Guangzhou Medical University of Guangzhou Medical University, Guangzhou Medical University, Guangzhou, Guangdong 510095, China 4 Department of Hematology, Guangdong Provincial People’s Hospital, Guangzhou 510500, China 5 Department of Hematology, Nanfang Hospital, Guangzhou 510500, China 6 Department of Respiratory Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China 7 Department of Hematology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510500, China 8 The First Affiliated Hospital, University of Zhengzhou, Zhengzhou 450000, China 9 Affiliated Caner Hospital and Institute of Guangzhou Medical University, Guangzhou 510095, China 10 Department of Hematology, Medical College, Jinan University, Guangzhou 510632, China 11 Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1HH, England, UK Correspondence to: Peng Li, email: li_peng@gibh.ac.cn Yao Yao, email: yao_yao@gibh.ac.cn Keywords: B-ALL; microenvironment; growth factors; drug screening; kinase inhibitors Abbreviations: B-ALL: B Acute lymphoblastic leukemia; OP9TA: OP9-derived adipocytes; CDK: cyclin-dependent kinase; FBS: fetal bovine serum; NSI: NOD/SCID/IL2Rg −/− mice Received: June 21, 2017 Accepted: October 28, 2017 Published: November 15, 2017 ABSTRACT Functional screening for compounds represents a major hurdle in the development of rational therapeutics for B-acute lymphoblastic leukemia (B-ALL). In addition, using cell lines as valid models for evaluating responses to novel drug therapies raises serious concerns, as cell lines are prone to genotypic/phenotypic drift and loss of heterogeneity in vitro . Here, we reported that OP9 cells, not OP9-derived adipocytes (OP9TA), support the growth of primary B-ALL cells in vitro . To identify the factors from OP9 cells that support the growth of primary B-ALL cells, we performed RNA-Seq to analyze the gene expression profiles of OP9 and OP9TA cells. We thus developed a defined, serum/feeder-free condition (FI76V) that can support the expansion of a range of clinically distinct primary B-ALL cells that still maintain their leukemia-initiating ability. We demonstrated the suitability of high-throughput drug screening based on our B-ALL cultured conditions. Upon screening 378 kinase inhibitors, we identified a cluster of 17 kinase inhibitors that can efficiently kill B-ALL cells in vitro . Importantly, we demonstrated the synergistic cytotoxicity of dinaciclib/BTG226 to B-ALL cells. Taken together, we developed a defined condition for the ex vivo expansion of primary B-ALL cells that is suitable for high-throughput screening of novel compounds.