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Dual blockade with ERBB2 and BCL2 inhibitors triggers additional reductions of BCL2 phosphorylation and myeloid cell leukemia-1 (MCL1) expression compared with single drug treatment. Dual therapy was synergistic at all tested doses, with a dose reduction index of up to 29 for lapatinib + venetoclax compared with venetoclax alone. Notably, these agents operated together and shifted cancer cells to a pro-apoptotic phenotype, resulting in increased mitochondrial cytochrome c release and activated caspase-3-mediated cell death. IMPLICATIONS These findings warrant study of ERBB2 and BCL2 combination therapy in patients with MDS and AML. VISUAL OVERVIEW http//mcr.aacrjournals.org/content/molcanres/19/5/886/F1.large.jpg.Anaplastic large cell lymphoma (ALCL) is an aggressive type of non-Hodgkin lymphoma. More than three-fourths of anaplastic lymphoma kinase (ALK)-positive ALCL cases express the nucleophosmin 1 (NPM1)-ALK fusion gene as a result of t(2;5) chromosomal translocation. The homodimerization of NPM1-ALK fusion protein mediates constitutive activation of the chimeric tyrosine kinase activity and downstream signaling pathways responsible for lymphoma cell proliferation and survival. Bafilomycin A1 research buy Gilteritinib is a tyrosine kinase inhibitor recently approved by the FDA for the treatment of FMS-like tyrosine kinase mutation-positive acute myeloid leukemia. In this study, we demonstrate for the first time gilteritinib-mediated growth inhibitory effects on NPM1-ALK-driven ALCL cells. We utilized a total of five ALCL model cell lines, including both human and murine. Gilteritinib treatment inhibits NPM1-ALK fusion kinase phosphorylation and downstream signaling, resulting in induced apoptosis. Gilteritinib-mediated apoptosis was associated with caspase 3/9, PARP cleavage, the increased expression of proapoptotic protein BAD, and decreased expression of antiapoptotic proteins, survivin and MCL-1. We also found downregulation of fusion kinase activity resulted in decreased c-Myc protein levels. Furthermore, cell-cycle analysis indicated gilteritinib induced G0-G1-phase cell-cycle arrest and reduced CD30 expression. In summary, our preclinical studies explored the novel therapeutic potential of gilteritinib in the treatment of ALCL cells expressing NPM1-ALK and potentially in other ALK or ALK fusion-driven hematologic or solid malignancies. IMPLICATIONS Our preclinical results explore the use of gilteritinib for the treatment of NPM1-ALK-driven ALCL cells and pave a path for developing future clinical trials. VISUAL OVERVIEW http//mcr.aacrjournals.org/content/molcanres/19/5/913/F1.large.jpg.Reference genome fidelity is critically important for genome wide association studies, yet most vary widely from the study population. A typical whole genome sequencing approach implies short-read technologies resulting in fragmented assemblies with regions of ambiguity. Further information is lost by economic necessity when genotyping populations, as lower resolution technologies such as genotyping arrays are commonly used. Here, we present a phased reference genome for Canis lupus familiaris using high molecular weight DNA-sequencing technologies. We tested wet laboratory and bioinformatic approaches to demonstrate a minimum workflow to generate the 2.4 gigabase genome for a Labrador Retriever. The de novo assembly required eight Oxford Nanopore R9.4 flowcells (∼23X depth) and running a 10X Genomics library on the equivalent of one lane of an Illumina NovaSeq S1 flowcell (∼88X depth), bringing the cost of generating a nearly complete reference genome to less than $10K (USD). Mapping of short-read data from 10 Labrador Retrievers against this reference resulted in 1% more aligned reads versus the current reference (CanFam3.1, P less then 0.001), and a 15% reduction of variant calls, increasing the chance of identifying true, low-effect size variants in a genome-wide association studies. We believe that by incorporating the cost to produce a full genome assembly into any large-scale genotyping project, an investigator can improve study power, decrease costs, and optimize the overall scientific value of their study.By extending synthesis opposite from a diverse array of DNA lesions, DNA polymerase (Pol) ζ performs a crucial role in translesion synthesis (TLS). In yeast and cancer cells, Rev1 functions as an indispensable scaffolding component of Polζ and it imposes highly error-prone TLS upon Polζ. However, for TLS that occurs during replication in normal human cells, Rev1 functions instead as a scaffolding component of Pols η, ι, and κ and Rev1-dependent TLS by these Pols operates in a predominantly error-free manner. The lack of Rev1 requirement for Polζ function in TLS in normal cells suggested that some other protein substitutes for this Rev1 role. Here, we identify a novel role of Polλ as an indispensable scaffolding component of Polζ. TLS studies opposite a number of DNA lesions support the conclusion that as an integral component, Polλ adapts Polζ-dependent TLS to operate in a predominantly error-free manner in human cells, essential for genome integrity and cellular homeostasis.Highly sensitive approaches to target insulin-expressing cells would allow more effective imaging, sorting, and analysis of pancreatic β-cells. Here, we introduce the use of a reaction-based probe, diacetylated Zinpyr1 (DA-ZP1), to image pancreatic β-cells and β-like cells derived from human pluripotent stem cells. We harness the high intracellular zinc concentration of β-cells to induce a fluorescence signal in cells after administration of DA-ZP1. Given its specificity and rapid uptake by cells, we used DA-ZP1 to purify live stem cell-derived β-like cells as confirmed by immunostaining analysis. We tested the ability of DA-ZP1 to image transplanted human islet grafts and endogenous mouse pancreatic islets in vivo after its systemic administration into mice. Thus, DA-ZP1 enables purification of insulin-secreting β-like cells for downstream applications, such as functional studies, gene-expression, and cell-cell interaction analyses and can be used to label engrafted human islets and endogenous mouse islets in vivo.