Tumour necrosis factor receptor-associated factor 7 drives leukaemogenesis through the TWIST1-P2RX1-Ca2+ axis in a mouse model of acute myeloid leukaemia

Tumour necrosis factor receptor-associated factor 7 (TRAF7), an E3 ubiquitin ligase, regulates multiple signalling pathways through posttranslational modifications. However, its role in acute myeloid leukaemia (AML) remains controversial and poorly understood. Analysis of public AML datasets and validation using in-house samples were conducted to evaluate TRAF7 expression in bone marrow samples from AML patients and to assess its potential as a prognostic marker. Gain- and loss-of-function studies were performed in AML cell lines, primary CD34+ cells and a xenograft mouse model to characterize the role of TRAF7 in AML. RNA sequencing was employed to elucidate the mechanisms underlying the pro-leukaemic activity of TRAF7, and a ubiquitination assay was used to identify the substrate of TRAF7. TRAF7 is highly expressed in AML, particularly in the M5 subtype, and its upregulation serves as a novel independent prognostic marker for poor clinical outcomes. Functional studies demonstrate that TRAF7 promotes AML cell proliferation in vitro and leukaemogenesis in a human AML xenograft model. Mechanistically, TRAF7 interacts with TWIST1 and mediates its K63-linked polyubiquitination, enhancing TWIST1 nuclear localization. TWIST1 directly transcriptionally activates P2RX1, which increases mitochondrial calcium levels, respiratory activity, and ATP production, thereby fuelling leukaemic growth. Taken together, our study identifies TRAF7 as a novel tumour promoter in AML via the TWIST1–P2RX1-calcium axis, highlighting its role as a prognostic biomarker. Although TRAF7 represents a potential therapeutic target, its clinical applicability remains hypothetical in the absence of direct inhibitor studies.