Kusterer Mira, Lahnalampi Mari, Voutilainen Minna, Brand Alexandra, Pennisi Sandra, Norona Johana, Gentile Gaia, Herzog Heike, Greve Gabriele, Lübbert Michael, Sipola Mikko, Kaartinen Emma, Sankowski Roman, Prinz Marco, Killmer Saskia, Lago Marilyn S, Bengsch Bertram, Cysar Stepan R, Aumann Konrad, Werner Martin, Duyster Justus, Lohi Olli, Heinäniemi Merja, Duque-Afonso Jesús
Department of Hematology, Oncology, Stem Cell Transplantation Faculty of Medicine, University of Freiburg Medical Center Freiburg Germany.
Institute of Biomedicine School of Medicine, University of Eastern Finland Kuopio Finland.
Hemasphere. 2025 Feb 3;9(2):e70071. doi: 10.1002/hem3.70071. eCollection 2025 Feb.
Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. The translocation t(1;19), encoding the TCF3-PBX1 fusion, is associated with intermediate risk and central nervous system (CNS) infiltration at relapse. Using our previously generated TCF3-PBX1 conditional knock-in mice, we established a model to study relapsed clones after in vivo chemotherapy treatment, CNS infiltration, and clonal dynamic evolution of phenotypic diversity at the single cell-level using next-generation sequencing technologies and mass cytometry. Mice transplanted with TCF3-PBX1 leukemia cells and treated with vehicle succumbed to disease, whereas 40% of treated mice with prednisolone or daunorubicin survived. Bulk and single-cell RNA sequencing of FACS-sorted GFP+ cells from TCF3-PBX1 leukemias arising after chemotherapy treatment revealed that apoptosis, interleukin-, and TGFβ-signaling pathways were regulated in CNS-infiltrating leukemic cells. Across tissues, upregulation of the MYC signaling pathway was detected in persisting leukemic cells and its downregulation by BRD3/4 inhibition increased sensitivity to chemotherapy. In TCF3-PBX1 leukemia cells collected after chemotherapy treatment, mass cytometry identified increased phosphorylation of STAT3/5 upon preBCR stimulation, which was susceptible to inhibition by the proteasome inhibitor bortezomib. In summary, we developed a TCF3-PBX1 ALL mouse model and characterized relapsed disease after in vivo chemotherapy and cell phenotype dependence on microenvironment. Transcriptomics and phospho-proteomics revealed distinct pathways that may underlie chemotherapy resistance and might be suitable for pharmacological interventions in human ALL.
急性淋巴细胞白血病（ALL）是儿童期最常见的癌症。编码TCF3-PBX1融合蛋白的t(1;19)易位与复发时的中危及中枢神经系统（CNS）浸润相关。利用我们之前构建的TCF3-PBX1条件性敲入小鼠，我们建立了一个模型，用于研究体内化疗治疗后的复发克隆、CNS浸润以及使用下一代测序技术和质谱流式细胞术在单细胞水平上的表型多样性的克隆动态进化。移植了TCF3-PBX1白血病细胞并接受载体处理的小鼠死于疾病，而40%接受泼尼松龙或柔红霉素治疗的小鼠存活。对化疗治疗后出现的TCF3-PBX1白血病中通过荧光激活细胞分选（FACS）分选的GFP+细胞进行大量和单细胞RNA测序，结果显示CNS浸润的白血病细胞中凋亡、白细胞介素和TGFβ信号通路受到调控。在各个组织中，在持续存在的白血病细胞中检测到MYC信号通路的上调，而通过抑制BRD3/4使其下调可增加对化疗的敏感性。在化疗治疗后收集的TCF3-PBX1白血病细胞中，质谱流式细胞术确定前B细胞受体（preBCR）刺激后STAT3/5的磷酸化增加，这对蛋白酶体抑制剂硼替佐米敏感。总之，我们开发了一种TCF3-PBX1 ALL小鼠模型，并对体内化疗后的复发性疾病以及细胞表型对微环境的依赖性进行了表征。转录组学和磷酸蛋白质组学揭示了可能是化疗耐药基础的不同通路，这些通路可能适用于人类ALL的药物干预。
