Asciminib antagonizes transplantable BCR::ABL1-positive lymphoid blast crisis in vivo by targeting malignant stem cells.

Philadelphia chromosome-positive (Ph+) lymphoid blast crisis (BC), emanating from chronic myeloid leukemia (CML), is a fatal disease with limited treatment options. Asciminib (ABL001) is a novel selective allosteric inhibitor of the ABL kinase with high efficacy against TKI-resistant BCR::ABL1. In this study, we demonstrate significant suppression of an aggressive B-lymphoblastic disease and restoration of normal hematopoiesis in an inducible transgenic mouse model of p210-BCR::ABL1-positive CML-BC.

Activating mutations in JAK2 and CALR differentially affect intracellular calcium flux in store operated calcium entry.

Background: Calcium (Ca) signaling regulates various vital cellular functions, including integrin activation and cell migration. Store-operated calcium entry (SOCE) via calcium release-activated calcium (CRAC) channels represents a major pathway for Ca influx from the extracellular space in multiple cell types. The impact of JAK2-V617F and CALR mutations which are disease initiating in myeloproliferative neoplasms (MPN) on SOCE, calcium flux from the endoplasmic reticulum (ER) to the cytosol, and related key signaling pathways in the presence or absence of erythropoietin (EPO) or thrombopoietin (TPO) is poorly understood.

Calreticulin and JAK2V617F driver mutations induce distinct mitotic defects in myeloproliferative neoplasms.

Myeloproliferative neoplasms (MPNs) encompass a diverse group of hematologic disorders driven by mutations in JAK2, CALR, or MPL. The prevailing working model explaining how these driver mutations induce different disease phenotypes is based on the decisive influence of the cellular microenvironment and the acquisition of additional mutations. Here, we report increased levels of chromatin segregation errors in hematopoietic cells stably expressing CALRdel52 or JAK2V617F mutations.

Proinflammatory phenotype of iPS cell-derived JAK2 V617F megakaryocytes induces fibrosis in 3D in vitro bone marrow niche.

The myeloproliferative disease polycythemia vera (PV) driven by the JAK2 V617F mutation can transform into myelofibrosis (post-PV-MF). It remains an open question how JAK2 V617F in hematopoietic stem cells induces MF. Megakaryocytes are major players in murine PV models but are difficult to study in the human setting.