Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023467 (acute myeloid leukemia)
 35,200 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Leukemia stem cells (LSCs) initiate and sustain the acute myeloid leukemia (AML) clonal hierarchy and possess biological properties rendering them resistant to conventional chemotherapy. The poor survival of AML patients raises expectations that LSC-targeted therapies might achieve durable remissions. We report that an anti-interleukin-3 (IL-3) receptor alpha chain (CD123)-neutralizing antibody (7G3) targeted AML-LSCs, impairing homing to bone marrow (BM) and activating innate immunity of nonobese diabetic/severe-combined immunodeficient (NOD/SCID) mice. 7G3 treatment profoundly reduced AML-LSC engraftment and improved mouse survival. Mice with pre-established disease showed reduced AML burden in the BM and periphery and impaired secondary transplantation upon treatment, establishing that AML-LSCs were directly targeted. 7G3 inhibited IL-3-mediated intracellular signaling of isolated AML CD34(+)CD38(-) cells in vitro and reduced their survival. These results provide clear validation for therapeutic monoclonal antibody (mAb) targeting of AML-LSCs and for translation of in vivo preclinical research findings toward a clinical application.
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PMID:Monoclonal antibody-mediated targeting of CD123, IL-3 receptor alpha chain, eliminates human acute myeloid leukemic stem cells. 1957 May 12

Xenotransplantation of human acute myeloid leukemia (AML) in immunocompromised animals has been critical for defining leukemic stem cells. However, existing immunodeficient strains of mice have short life spans and low levels of AML cell engraftment, hindering long-term evaluation of primary human AML biology. A recent study suggested that NOD/LtSz-scid IL2Rgammac null (NSG) mice have enhanced AML cell engraftment, but this relied on technically challenging neonatal injections. Here, we performed extensive analysis of AML engraftment in adult NSG mice using tail vein injection. Of the 35 AML samples analyzed, 66% showed bone marrow engraftment over 0.1%. Further, 37% showed high levels of engraftment (>10%), with some as high as 95%. A 2-44-fold expansion of AML cells was often seen. Secondary and tertiary recipients showed consistent engraftment, with most showing further AML cell expansion. Engraftment did not correlate with French-American-British subtype or cytogenetic abnormalities. However, samples with FLT3 mutations showed a higher probability of engraftment than FLT3 wild type. Importantly, animals developed organomegaly and a wasting illness consistent with advanced leukemia. We conclude that the NSG xenotransplantation model is a robust model for human AML cell engraftment, which will allow better characterization of AML biology and testing of new therapies.
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PMID:A robust xenotransplantation model for acute myeloid leukemia. 1962 50

In this study, we tested if FLT3/internal tandem duplication (ITD) in acute myeloid leukemia (AML) might occur at different hierarchical stages during leukemogenesis. In 56 AML cases, 10 showed FLT3/ITD (single ITD=5; multiple ITD=5). Myeloblasts from seven cases (CD34-selected=4; unselected=3) were transplanted into NOD/SCID mice. Five cases engrafted successfully into 14 mice. Two patients carried single FLT3/ITD subclones, which were maintained during primary and secondary transplantations. In three patients with multiple FLT3/ITD subclones, some subclones persisted or expanded while others diminished upon transplantation. Their different engraftment capabilities in NOD/SCID mice supported the proposition that FLT3/ITD might occur at different stages during leukemogenesis.
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PMID:FLT3/internal tandem duplication subclones in acute myeloid leukemia differ in their engraftment potential in NOD/SCID mice. 1968 12

To investigate human hematopoiesis and immunity in vivo, we have been making efforts to reconstitute these systems in mice by intravenously injecting purified human stem cells into NOD/SCID/IL2rgKO newborns. This xenogeneic transplantation system supports long-term engraftment, multi-lineage differentiation, and self-renewal capacity of human cord blood-derived hematopoietic stem cells (HSCs). We here introduce our recent application of the NOD/SCID/IL2rgKO newborn xenotransplant system to create in vivo models for human hematological malignancies and to understand pathophysiology of human AML.
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PMID:[Humanized model for acute myeloid leukemia]. 1986 Feb 2

Stem cells of acute myeloid leukemia (AML) have been identified as immunodeficient mouse-repopulating cells with a Lin(-)CD34(+)38(-) phenotype similar to normal hematopoietic stem cells. To identify the leukemia-propagating stem cell fraction of Philadelphia chromosome-positive (Ph(+)) leukemia, we serially transplanted human leukemia cells from patients with chronic myeloid leukemia blast crisis (n = 3) or Ph(+) acute lymphoblastic leukemia (n = 3) into NOD/SCID/IL-2Rgammac(-/-) mice. Engrafted cells were almost identical to the original leukemia cells as to phenotypes, IGH rearrangements, and karyotypes. CD34(+)CD38(-)CD19(+), CD34(+)38(+)CD19(+), and CD34(-)CD38(+)CD19(+) fractions could self-renew and transfer the leukemia, whereas the CD34(-)CD38(+)CD19(+) fraction did not stably propagate in NOD/SCID mice. These findings suggest that leukemia-repopulating cells in transformed Ph(+) leukemia are included in a lineage-committed but multilayered fraction, and that CD34(+) leukemia cells potentially emerge from CD34(-) populations.
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PMID:Irrespective of CD34 expression, lineage-committed cell fraction reconstitutes and re-establishes transformed Philadelphia chromosome-positive leukemia in NOD/SCID/IL-2Rgammac-/- mice. 2002 84

Cancer stem cells have been proposed to be important for initiation, maintenance and recurrence of various malignancies, including acute myeloid leukemia (AML). We have previously reported that CD34+CD38- human primary AML stem cells residing in the endosteal region of the bone marrow are relatively chemotherapy resistant. Using a NOD/SCID/IL2rgamma(null) mouse model of human AML, we now show that the AML stem cells in the endosteal region are cell cycle quiescent and that these stem cells can be induced to enter the cell cycle by treatment with granulocyte colony-stimulating factor (G-CSF). In combination with cell cycle-dependent chemotherapy, G-CSF treatment significantly enhances induction of apoptosis and elimination of human primary AML stem cells in vivo. The combination therapy leads to significantly increased survival of secondary recipients after transplantation of leukemia cells compared with chemotherapy alone.
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PMID:Induction of cell cycle entry eliminates human leukemia stem cells in a mouse model of AML. 2036 32

Acute myeloid leukemia (AML) is maintained by rare leukemia-initiating cells (L-ICs). FLT3 and/or PI3K pathways are often dysregulated in AML and may be important for L-IC survival. The presence of PI3K pathway intermediate integrin linked kinase (ILK), and FLT3 was confirmed in five L-IC-enriched AML patient samples. Treatment of AML cells with QLT0267, an inhibitor of ILK and FLT3, decreased survival of long-term suspension culture-initiating cells and NOD/SCID mouse L-IC. In contrast, little toxicity toward normal bone marrow progenitors was observed, demonstrating that candidate leukemic stem cells can be eliminated by inhibition of these targets while normal hematopoietic counterparts are spared.
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PMID:Targeting integrin linked kinase and FMS-like tyrosine kinase-3 is cytotoxic to acute myeloid leukemia stem cells but spares normal progenitors. 2019 63

We have evaluated the carbohydrate antigen Lewis(Y) (Le(Y)) as a potential target for T-cell immunotherapy of hematological neoplasias. Analysis of 81 primary bone marrow samples revealed moderate Le(Y) expression on plasma cells of myeloma patients and myeloblasts of patients with acute myeloid leukemia (AML) (52 and 46% of cases, respectively). We developed a retroviral vector construct encoding a chimeric T-cell receptor that recognizes the Le(Y) antigen in a major histocompatibility complex-independent manner and delivers co-stimulatory signals to achieve T-cell activation. We have shown efficient transduction of peripheral blood-derived T cells with this construct, resulting in antigen-restricted interferon-gamma secretion and cell lysis of Le(Y)-expressing tumor cells. In vivo activity of gene-modified T cells was demonstrated in the delayed growth of myeloma xenografts in NOD/SCID mice, which prolonged survival. Therefore, targeting Le(Y)-positive malignant cells with T cells expressing a chimeric receptor recognizing Le(Y) was effective both in vitro and in a myeloma mouse model. Consequently, we plan to use T cells manufactured under Good Manufacturing Practice conditions in a phase I immunotherapy study for patients with Le(Y)-positive myeloma or AML.
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PMID:Gene-modified T cells as immunotherapy for multiple myeloma and acute myeloid leukemia expressing the Lewis Y antigen. 2020 May 63

Meisoindigo, a derivative of Indigo naturalis, has been used in China for chronic myeloid leukemia. In vitro cell line studies have shown that this agent might induce apoptosis and myeloid differentiation of acute myeloid leukemia (AML). In this study, we explored its mechanisms and potential in AML. NB4, HL-60, and U937 cells and primary AML cells were used to examine its effects and the NOD/SCID animal model was used to evaluate its in vivo activity. Meisoindigo inhibited the growth of leukemic cells by inducing marked apoptosis and moderate cell-cycle arrest at the G(0)/G(1) phase. It down-regulated anti-apoptotic Bcl-2, and up-regulated pro-apoptotic Bak and Bax and cell-cycle related proteins, p21and p27. Furthermore, it induced myeloid differentiation, as demonstrated by morphologic changes, up-regulation of CD11b, and increased nitroblue tetrazolium reduction activity in all cell lines tested. In addition, meisoindigo down-regulated the expression of human telomerase reverse transcriptase and enhanced the cytotoxicity of conventional chemotherapeutic agents, cytarabine and idarubicin. As with the results from cell lines, meisoindigo also induced apoptosis, up-regulated p21 and p27, and down-regulated Bcl-2 in primary AML cells. The in vivo anti-leukemic activity of meisoindigo was also demonstrated by decreased spleen size in a dose-dependent manner. Taking these results together, meisoindigo is a potential agent for AML.
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PMID:Meisoindigo is a promising agent with in vitro and in vivo activity against human acute myeloid leukemia. 2023 51

Human mesenchymal stem cells form the supportive structure in which the functional cells of a differentiated tissue reside. We describe the creation of ectopic niches within polyurethane scaffolds coated with human mesenchymal stem cells. When implanted subcutaneously in NOD/SCID mice, these niches supported engraftment of primary human acute myeloid leukemia cells. The scaffolds showed vascularization and presence of osteoclasts and adipocytes, suggestive of an organizing human bone marrow microenvironment in the murine host. The chemokine stromal-derived factor-1 (SDF-1 or CXCL12) and its receptor CXCR4 are critical for homing and migration of acute myeloid leukemia. We found that a CXCR4 antagonist could disrupt homing to the ectopic niches, possibly by modulation of the mesenchymal stroma. We believe that these scaffold niches provide a new and powerful tool to study the leukemia stem cell microenvironment and may be useful for identification of novel drug targets.
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PMID:Ectopic human mesenchymal stem cell-coated scaffolds in NOD/SCID mice: an in vivo model of the leukemia niche. 2058 11


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