CD9 shapes glucocorticoid sensitivity in pediatric B-cell precursor acute lymphoblastic leukemia

作者：Chi Zhang, Kathy Yuen Yee Chan, Wing Hei Ng, John Tak Kit Cheung, Qiwei Sun, Han Wang, Po Yee Chung, Frankie Wai Tsoi Cheng, Alex Wing Kwan Leung, Xiao‐Bing Zhang, Po Yi Lee, Siu Ping Fok, Guanglan Lin, Ellen Poon, Jianhua Feng, Yan‐Lai Tang, Xue‐Qun Luo, Libin Huang, Wei Kang, Patrick Ming‐Kuen Tang, Junbin Huang, Chun Chen, Junchao Dong, Ester Mejstříková, Jiaoyang Cai, Yu Liu, Shuhong Shen, Jun J. Yang, Patrick Man Pan Yuen, Chi Kong Li, Kam Tong Leung · 发表于：Haematologica · 年份：2024 · DOI：10.3324/haematol.2023.282952 · 被引用次数：2 · 研究领域：Immune Cell Function and Interaction、Lung Cancer Research Studies、Acute Lymphoblastic Leukemia research

Resistance to glucocorticoids (GC), the common agents for remission induction in pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL), poses a significant therapeutic hurdle. Therefore, dissecting the mechanisms shaping GC resistance could lead to new treatment modalities. Here, we showed that CD9- BCP-ALL cells were preferentially resistant to prednisone and dexamethasone over other standard cytotoxic agents. Concordantly, we identified significantly more poor responders to the prednisone prephase among BCP-ALL patients with a CD9- phenotype, especially for those with adverse presenting features including older age, higher white cell count and BCR-ABL1. Furthermore, gain- and loss-offunction experiments dictated a definitive functional linkage between CD9 expression and GC susceptibility, as demonstrated by the reversal and acquisition of relative GC resistance in CD9low and CD9high BCP-ALL cells, respectively. Despite physical binding to the GC receptor NR3C1, CD9 did not alter its expression, phosphorylation or nuclear translocation but potentiated the induction of GC-responsive genes in GC-resistant cells. Importantly, the MEK inhibitor trametinib exhibited higher synergy with GC against CD9- than CD9+ lymphoblasts to reverse drug resistance in vitro and in vivo. Collectively, our results elucidate a previously unrecognized regulatory function of CD9 in GC sensitivity, and inform new strategies for management of children with resistant BCP-ALL.