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Blood Cancer Journal May 2021Approximately 30% of patients with newly diagnosed acute myeloid leukemia (AML) harbor mutations in the fms-like tyrosine kinase 3 (FLT3) gene. While the adverse... (Review)
Review
Approximately 30% of patients with newly diagnosed acute myeloid leukemia (AML) harbor mutations in the fms-like tyrosine kinase 3 (FLT3) gene. While the adverse prognostic impact of FLT3-ITD in AML has been clearly proven, the prognostic significance of FLT3-TKD remains speculative. Current guidelines recommend rapid molecular testing for FLT3 at diagnosis and earlier incorporation of targeted agents to achieve deeper remissions and early consideration for allogeneic stem cell transplant (ASCT). Mounting evidence suggests that FLT3 can emerge at any timepoint in the disease spectrum emphasizing the need for repetitive mutational testing not only at diagnosis but also at each relapse. The approval of multi-kinase FLT3 inhibitor (FLT3i) midostaurin with induction therapy for newly diagnosed FLT3 AML, and a more specific, potent FLT3i, gilteritinib as monotherapy for relapsed/refractory (R/R) FLT3 AML have improved outcomes in patients with FLT3 AML. Nevertheless, the short duration of remission with single-agent FLT3i's in R/R FLT3 AML in the absence of ASCT, limited options in patients refractory to gilteritinib therapy, and diverse primary and secondary mechanisms of resistance to different FLT3i's remain ongoing challenges that compel the development and rapid implementation of multi-agent combinatorial or sequential therapies for FLT3 AML.
Topics: Aniline Compounds; Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Disease Management; Drug Resistance, Neoplasm; Humans; Leukemia, Myeloid, Acute; Mutation; Protein Kinase Inhibitors; Pyrazines; Staurosporine; fms-Like Tyrosine Kinase 3
PubMed: 34045454
DOI: 10.1038/s41408-021-00495-3 -
Gastroenterology Nov 2019Epithelial tight junctions are compromised in gastrointestinal disease. Processes that contribute to the resulting barrier loss include endocytic occludin removal from...
BACKGROUND & AIMS
Epithelial tight junctions are compromised in gastrointestinal disease. Processes that contribute to the resulting barrier loss include endocytic occludin removal from the tight junction and reduced occludin expression. Nevertheless, the relatively-normal basal phenotype of occludin knockout (KO) mice has been taken as evidence that occludin does not contribute to gastrointestinal barrier function. We asked whether stress could unmask occludin functions within intestinal epithelia.
METHODS
Wildtype (WT), universal and intestinal epithelial-specific occludin KO, and villin-EGFP-occludin transgenic mice as well as WT and occludin knockdown (KD) Caco-2 cell monolayers were challenged with DSS, TNBS, staurosporine, 5-FU, or TNF. Occludin and caspase-3 expression were assessed in patient biopsies.
RESULTS
Intestinal epithelial occludin loss limited severity of DSS- and TNBS-induced colitis due to epithelial resistance to apoptosis; activation of both intrinsic and extrinsic apoptotic pathways was blocked in occludin KO epithelia. Promoter analysis revealed that occludin enhances CASP3 transcription and, conversely, that occludin downregulation reduces caspase-3 expression. Analysis of biopsies from Crohn's disease and ulcerative colitis patients and normal controls demonstrated that disease-associated occludin downregulation was accompanied by and correlated with reduced caspase-3 expression. In vitro, cytokine-induced occludin downregulation resulted in reduced caspase-3 expression and resistance to intrinsic and extrinsic pathway apoptosis, demonstrating an overall protective effect of inflammation-induced occludin loss.
CONCLUSIONS
The tight junction protein occludin regulates apoptosis by enhancing caspase-3 transcription. These data suggest that reduced epithelial caspase-3 expression downstream of occludin downregulation is a previously-unappreciated anti-apoptotic process that contributes to mucosal homeostasis in inflammatory conditions.
Topics: Animals; Apoptosis; Caco-2 Cells; Case-Control Studies; Caspase 3; Colitis; Colitis, Ulcerative; Colon; Crohn Disease; Dextran Sulfate; Disease Models, Animal; Epithelial Cells; Humans; Intestinal Mucosa; Mice, Inbred C57BL; Mice, Knockout; Occludin; Signal Transduction; Trinitrobenzenesulfonic Acid; Zonula Occludens-1 Protein
PubMed: 31401143
DOI: 10.1053/j.gastro.2019.07.058 -
Blood Apr 2020Systemic mastocytosis (SM) has greatly benefited from the broad application of precision medicine techniques to hematolymphoid neoplasms. Sensitive detection of the... (Review)
Review
Systemic mastocytosis (SM) has greatly benefited from the broad application of precision medicine techniques to hematolymphoid neoplasms. Sensitive detection of the recurrent KIT D816V mutation and use of next-generation sequencing (NGS) panels to profile the genetic landscape of SM variants have been critical adjuncts to the diagnosis and subclassification of SM, and development of clinical-molecular prognostic scoring systems. Multilineage KIT involvement and multimutated clones are characteristic of advanced SM (advSM), especially SM with an associated hematologic neoplasm (AHN). A major challenge is how to integrate conventional markers of mast cell disease burden (percentage of bone marrow mast cell infiltration and serum tryptase levels) with molecular data (serial monitoring of both KIT D816V variant allele frequency and NGS panels) to lend more diagnostic and prognostic clarity to the heterogeneous clinical presentations and natural histories of advSM. The approval of the multikinase/KIT inhibitor midostaurin has validated the paradigm of KIT inhibition in advSM, and the efficacy and safety of second-generation agents, such as the switch-control inhibitor ripretinib (DCC-2618) and the D816V-selective inhibitor avapritinib (BLU-285) are being further defined in ongoing clinical trials. Looking forward, perhaps the most fruitful marriage of the advances in molecular genetics and treatment will be the design of adaptive basket trials that combine histopathology and genetic profiling to individualize treatment approaches for patients with diverse AHNs and relapsed/refractory SM.
Topics: Animals; Chromosome Aberrations; Hematopoietic Stem Cell Transplantation; Humans; Mastocytosis, Systemic; Mutation; Prognosis; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-kit; Pyrazoles; Pyrroles; Staurosporine; Triazines
PubMed: 32106312
DOI: 10.1182/blood.2019000932 -
Blood Jun 2021In the international randomized phase 3 RATIFY (Randomized AML Trial In FLT3 in patients less than 60 Years old) trial, the multikinase inhibitor midostaurin... (Clinical Trial)
Clinical Trial
In the international randomized phase 3 RATIFY (Randomized AML Trial In FLT3 in patients less than 60 Years old) trial, the multikinase inhibitor midostaurin significantly improved overall and event-free survival in patients 18 to 59 years of age with FLT3-mutated acute myeloid leukemia (AML). However, only 59% of patients in the midostaurin arm achieved protocol-specified complete remission (CR), and almost half of patients achieving CR relapsed. To explore underlying mechanisms of resistance, we studied patterns of clonal evolution in patients with FLT3-internal tandem duplications (ITD)-positive AML who were entered in the RATIFY or German-Austrian Acute Myeloid Leukemia Study Group 16-10 trial and received treatment with midostaurin. To this end, paired samples from 54 patients obtained at time of diagnosis and at time of either relapsed or refractory disease were analyzed using conventional Genescan-based testing for FLT3-ITD and whole exome sequencing. At the time of disease resistance or progression, almost half of the patients (46%) became FLT3-ITD negative but acquired mutations in signaling pathways (eg, MAPK), thereby providing a new proliferative advantage. In cases with FLT3-ITD persistence, the selection of resistant ITD clones was found in 11% as potential drivers of disease. In 32% of cases, no FLT3-ITD mutational change was observed, suggesting either resistance mechanisms bypassing FLT3 inhibition or loss of midostaurin inhibitory activity because of inadequate drug levels. In summary, our study provides novel insights into the clonal evolution and resistance mechanisms of FLT3-ITD-mutated AML under treatment with midostaurin in combination with intensive chemotherapy.
Topics: Adolescent; Adult; Aged; Clonal Evolution; Female; Humans; Leukemia, Myeloid, Acute; Male; Middle Aged; Mutation; Staurosporine; Tandem Repeat Sequences; Exome Sequencing; fms-Like Tyrosine Kinase 3
PubMed: 33598693
DOI: 10.1182/blood.2020007626 -
Journal of Cachexia, Sarcopenia and... Oct 2022Several studies have examined gut microbiota and sarcopenia using 16S ribosomal RNA amplicon sequencing; however, this technique may not be able to identify altered... (Observational Study)
Observational Study
BACKGROUND
Several studies have examined gut microbiota and sarcopenia using 16S ribosomal RNA amplicon sequencing; however, this technique may not be able to identify altered specific species and functional capacities of the microbes. We performed shotgun metagenomic sequencing to compare the gut microbiome composition and function between individuals with and without sarcopenia.
METHODS
Participants were from a community-based observational study conducted among the residents of rural areas in China. Appendicular skeletal muscle mass was assessed using direct segmental multi-frequency bioelectrical impedance and grip strength using a Jamar Hydraulic Hand dynamometer. Physical performance was evaluated using the Short Physical Performance Battery, 5-time chair stand test and gait speed with the 6 m walk test. Sarcopenia and its severity were diagnosed according to the Asian Working Group for Sarcopenia 2019 algorithm. The gut microbiome was profiled by shotgun metagenomic sequencing to determine the microbial composition and function. A gut microbiota-based model for classification of sarcopenia was constructed using the random forest model, and its performance was assessed using the area under receiver-operating characteristic curve (AUC).
RESULTS
The study sample included 1417 participants (women: 58.9%; mean age: 63.3 years; sarcopenia prevalence: 10.0%). β-diversity indicated by Bray-Curtis distance (genetic level: P = 0.004; taxonomic level of species: P = 0.020), but not α-diversity indicated by Shannon index (genetic level: P = 0.962; taxonomic level of species: P = 0.922), was significantly associated with prevalent sarcopenia. After adjusting for potential confounders, participants with sarcopenia had higher relative abundance of Desulfovibrio piger (P = 0.003, Q = 0.090), Clostridium symbiosum (P < 0.001, Q = 0.035), Hungatella effluvii (P = 0.003, Q = 0.090), Bacteroides fluxus (P = 0.002, Q = 0.089), Absiella innocuum (P = 0.002, Q = 0.072), Coprobacter secundus (P = 0.002, Q = 0.085) and Clostridium citroniae (P = 0.001, Q = 0.060) than those without sarcopenia. The relative abundance of six species (Desulfovibrio piger, Clostridium symbiosum, Hungatella effluvii, Bacteroides fluxus, Absiella innocuum, and Clostridium citroniae) was also positively associated with sarcopenia severity. A differential species-based model was constructed to separate participants with sarcopenia from controls. The value of the AUC was 0.852, suggesting that model has a decent discriminative performance. Desulfovibrio piger ranked the highest in this model. Functional annotation analysis revealed that the phenylalanine, tyrosine, and tryptophan biosynthesis were depleted (P = 0.006, Q = 0.071), while alpha-Linolenic acid metabolism (P = 0.008, Q = 0.094), furfural degradation (P = 0.001, Q = 0.029) and staurosporine biosynthesis (P = 0.006, Q = 0.072) were enriched in participants with sarcopenia. Desulfovibrio piger was significantly associated with staurosporine biosynthesis (P < 0.001).
CONCLUSIONS
This large population-based observational study provided empirical evidence that alterations in the gut microbiome composition and function were observed among individuals with sarcopenia.
Topics: Bacteroides; Clostridiaceae; Clostridiales; Desulfovibrio; Female; Furaldehyde; Gastrointestinal Microbiome; Humans; Middle Aged; Phenylalanine; RNA, Ribosomal, 16S; Sarcopenia; Staurosporine; Tryptophan; Tyrosine; alpha-Linolenic Acid
PubMed: 35851765
DOI: 10.1002/jcsm.13037 -
Blood Jan 2020The acute myeloid leukemia (AML) treatment landscape has changed substantially since 2017. New targeted drugs have emerged, including venetoclax to target B-cell...
The acute myeloid leukemia (AML) treatment landscape has changed substantially since 2017. New targeted drugs have emerged, including venetoclax to target B-cell lymphoma 2, midostaurin and gilteritinib to target FLT3, and ivosidenib and enasidenib to target mutant isocitrate dehydrogenase 1 and 2, respectively. Other additions include reapproval of gemtuzumab ozogomycin to target CD33, glasdegib to target the hedgehog pathway, and a liposomal formulation of daunorubicin and cytarabine (CPX-351). Genomically heterogeneous AML has a tendency to evolve, particularly under selective treatment pressure. For decades, treatment decisions have largely centered around chemotherapy drug intensity. Physicians now have access to an increasing number of drugs with novel mechanisms of action and distinctive side-effect profiles. Key issues faced by hematologists in this era of new drugs include (1) the timely identification of actionable mutations at diagnosis and at relapse; (2) deciding which drug to use among several therapeutic options; and (3) increasing awareness of how to anticipate, mitigate, and manage common complications associated with these new agents. This article will use 3 case presentations to discuss some of the new treatment challenges encountered in AML management, with the goal of providing practical guidance to aid the practicing physician.
Topics: Adult; Aged; Aminopyridines; Aniline Compounds; Antineoplastic Agents; Biomarkers, Tumor; Bridged Bicyclo Compounds, Heterocyclic; Cytarabine; Daunorubicin; Female; Glycine; Humans; Isocitrate Dehydrogenase; Leukemia, Myeloid, Acute; Male; Molecular Targeted Therapy; Mutation; Prognosis; Pyrazines; Pyridines; Sialic Acid Binding Ig-like Lectin 3; Staurosporine; Sulfonamides; Triazines; fms-Like Tyrosine Kinase 3
PubMed: 31765470
DOI: 10.1182/blood.2019001239 -
Cell Death & Disease Oct 2023An important pathophysiological process of acute kidney injury (AKI) is mitochondrial fragmentation in renal tubular epithelial cells, which leads to cell death....
An important pathophysiological process of acute kidney injury (AKI) is mitochondrial fragmentation in renal tubular epithelial cells, which leads to cell death. Pyruvate kinase M2 (PKM2) is an active protein with various biological functions that participates in regulating glycolysis and plays a key role in regulating cell survival. However, the role and mechanism of PKM2 in regulating cell survival during AKI remain unclear. Here, we found that the phosphorylation of PKM2 contributed to the formation of the PKM2 dimer and translocation of PKM2 into the mitochondria after treatment with staurosporine or cisplatin. Mitochondrial PKM2 binds myosin heavy chain 9 (MYH9) to promote dynamin-related protein 1 (DRP1)-mediated mitochondrial fragmentation. Both in vivo and in vitro, PKM2-specific loss or regulation PKM2 activity partially limits mitochondrial fragmentation, alleviating renal tubular injury and cell death, including apoptosis, necroptosis, and ferroptosis. Moreover, staurosporine or cisplatin-induced mitochondrial fragmentation and cell death were reversed in cultured cells by inhibiting MYH9 activity. Taken together, our results indicate that the regulation of PKM2 abundance and activity to inhibit mitochondrial translocation may maintain mitochondrial integrity and provide a new therapeutic strategy for treating AKI.
Topics: Humans; Acute Kidney Injury; Cisplatin; Homeostasis; Mitochondria; Pyruvate Kinase; Staurosporine
PubMed: 37816709
DOI: 10.1038/s41419-023-06195-z -
Autophagy Mar 2020Macroautophagy/autophagy is generally regarded as a cytoprotective mechanism, and it remains a matter of controversy whether autophagy can cause cell death in mammals....
Macroautophagy/autophagy is generally regarded as a cytoprotective mechanism, and it remains a matter of controversy whether autophagy can cause cell death in mammals. Here, we show that chronic restraint stress suppresses adult hippocampal neurogenesis in mice by inducing autophagic cell death (ACD) of hippocampal neural stem cells (NSCs). We generated NSC-specific, inducible conditional knockout mice and found that they had an intact number of NSCs and neurogenesis level under chronic restraint stress and were resilient to stress- or corticosterone-induced cognitive and mood deficits. Corticosterone treatment of adult hippocampal NSC cultures induced ACD via SGK3 (serum/glucocorticoid regulated kinase 3) without signs of apoptosis. Our results demonstrate that ACD is biologically important in a mammalian system and would be an attractive target for therapeutic intervention for psychological stress-induced disorders.: AAV: adeno-associated virus; ACD: autophagic cell death; ACTB: actin, beta; Atg: autophagy-related; ASCL1/MASH1: achaete-scute family bHLH transcription factor 1; BafA: bafilomycin A; BrdU: Bromodeoxyuridine/5-bromo-2'-deoxyuridine; CASP3: caspase 3; cKO: conditional knockout; CLEM: correlative light and electron microscopy; CORT: corticosterone; CRS: chronic restraint stress; DAB: 3,3'-diaminobenzidine; DCX: doublecortin; DG: dentate gyrus; GC: glucocorticoid; GFAP: glial fibrillary acidic protein; HCN: hippocampal neural stem; i.p.: intraperitoneal; MAP1LC3B: microtubule-associated protein 1 light chain 3 beta; MKI67/Ki67: antigen identified by monoclonal antibody Ki 67; MWM: Morris water maze; Nec-1: necrostatin-1; NES: nestin; NR3C1/GR: nuclear receptor subfamily 3, group C, member 1; NSC: neural stem cell; PCD: programmed cell death; PFA: paraformaldehyde; PX: Phox homology; PtdIns3P: phosphatidylinositol-3-phosphate; RBFOX3/NeuN: RNA binding protein, fox-1 homolog (C. elegans) 3; SGK: serum/glucocorticoid-regulated kinases; SGZ: subgranular zone; SOX2: SRY (sex determining region Y)-box 2; SQSTM1: sequestosome 1; STS: staurosporine; TAM: tamoxifen; Ulk1: unc-51 like kinase 1; TUNEL: terminal deoxynucleotidyl transferase dUTP nick end labeling; VIM: vimentin; WT: wild type; ZFYVE1: zinc finger, FYVE domain containing 1; Z-VAD/Z-VAD-FMK: pan-caspase inhibitor.
Topics: Animals; Anxiety; Apoptosis; Autophagy; Autophagy-Related Protein 7; Cognition Disorders; Corticosterone; Depression; Doublecortin Protein; Gene Deletion; Gene Silencing; Hippocampus; Immediate-Early Proteins; Mice, Knockout; Necroptosis; Neural Stem Cells; Neurogenesis; Protein Serine-Threonine Kinases; Stress, Physiological
PubMed: 31234698
DOI: 10.1080/15548627.2019.1630222 -
Blood Advances Sep 2022We conducted a single-arm, phase 2 trial (German-Austrian Acute Myeloid Leukemia Study Group [AMLSG] 16-10) to evaluate midostaurin with intensive chemotherapy followed...
We conducted a single-arm, phase 2 trial (German-Austrian Acute Myeloid Leukemia Study Group [AMLSG] 16-10) to evaluate midostaurin with intensive chemotherapy followed by allogeneic hematopoietic-cell transplantation (HCT) and a 1-year midosta urin maintenance therapy in adult patients with acute myeloid leukemia (AML) and fms-related tyrosine kinase 3 (FLT3) internal tandem duplication (ITD). Patients 18 to 70 years of age with newly diagnosed FLT3-ITD-positive AML were eligible. Primary and key secondary endpoints were event-free survival (EFS) and overall survival (OS). Results were compared with a historical cohort of 415 patients treated on 5 prior AMLSG trials; statistical analysis was performed using a double-robust adjustment with propensity score weighting and covariate adjustment. Results were also compared with patients (18-59 years) treated on the placebo arm of the Cancer and Leukemia Group B (CALGB) 10603/RATIFY trial. The trial accrued 440 patients (18-60 years, n = 312; 61-70 years, n = 128). In multivariate analysis, EFS was significantly in favor of patients treated within the AMLSG 16-10 trial compared with the AMLSG control (hazard ratio [HR], 0.55; P < .001); both in younger (HR, 0.59; P < .001) and older patients (HR, 0.42; P < .001). Multivariate analysis also showed a significant beneficial effect on OS compared with the AMLSG control (HR, 0.57; P < .001) as well as to the CALGB 10603/RATIFY trial (HR, 0.71; P = .005). The treatment effect of midostaurin remained significant in sensitivity analysis including allogeneic HCT as a time-dependent covariate. Addition of midostaurin to chemotherapy was safe in younger and older patients. In comparison with historical controls, the addition of midostaurin to intensive therapy led to a significant improvement in outcome in younger and older patients with AML and FLT3-ITD. This trial is registered at clinicaltrialsregistry.eu as Eudra-CT number 2011-003168-63 and at clinicaltrials.gov as NCT01477606.
Topics: Adolescent; Adult; Aged; Hematopoietic Stem Cell Transplantation; Humans; Leukemia, Myeloid, Acute; Middle Aged; Protein-Tyrosine Kinases; Staurosporine; Young Adult; fms-Like Tyrosine Kinase 3
PubMed: 35486475
DOI: 10.1182/bloodadvances.2022007223 -
Theranostics 2020Peritoneal metastasis predicts poor prognosis of gastric cancer (GC) patients, and the underlying mechanisms are poorly understood. The 2-DIGE, MALDI-TOF/TOF MS and...
Peritoneal metastasis predicts poor prognosis of gastric cancer (GC) patients, and the underlying mechanisms are poorly understood. The 2-DIGE, MALDI-TOF/TOF MS and single-cell transcriptome were used to detect differentially expressed proteins among normal gastric mucosa, primary GC and peritoneal metastatic tissues. Lentiviruses carrying shRNA and transcription activator-like effector nuclease technology were used to knock down myosin heavy chain 9 (MYH9) expression in GC cell lines. Immunofluorescence, immune transmission electron microscopy, chromatin fractionation, co-immunoprecipitation, and assays for chromatin immunoprecipitation, dual luciferase reporter, agarose-oligonucleotide pull-down, flow cytometry and cell anoikis were performed to uncover nuclear MYH9-induced β-catenin () transcription . Nude mice and conditional transgenic mice were used to investigate the findings . We observed that MYH9 was upregulated in metastatic GC tissues and was associated with a poor prognosis of GC patients. Mechanistically, we confirmed that MYH9 was mainly localized in the GC cell nuclei by four potential nuclear localization signals. Nuclear MYH9 bound to the promoter through its DNA-binding domain, and interacted with myosin light chain 9, β-actin and RNA polymerase II to promote transcription, which conferred resistance to anoikis in GC cells and . Staurosporine reduced nuclear MYH9 S1943 phosphorylation to inhibit transcription, Wnt/β-catenin signaling activation and GC progression in both orthotropic xenograft GC nude mouse and transgenic GC mouse models. This study identified that nuclear MYH9-induced CTNNB1 expression promotes GC metastasis, which could be inhibited by staurosporine, indicating a novel therapy for GC peritoneal metastasis.
Topics: Animals; Anoikis; Cell Line, Tumor; Cell Movement; Cell Nucleus; Cell Proliferation; Chemotherapy, Adjuvant; Female; Gastrectomy; Gene Expression Regulation, Neoplastic; Gene Knockdown Techniques; Humans; Lung Neoplasms; Male; Mice; Mice, Transgenic; Myosin Heavy Chains; Phosphorylation; Promoter Regions, Genetic; Staurosporine; Stomach; Stomach Neoplasms; Transcriptional Activation; Up-Regulation; Wnt Signaling Pathway; Xenograft Model Antitumor Assays; beta Catenin
PubMed: 32685004
DOI: 10.7150/thno.46001