scholarly journals Low DICER1 expression is associated with attenuated neutrophil differentiation and autophagy of NB4 APL cells

2015 ◽  
Vol 98 (3) ◽  
pp. 357-363 ◽  
Author(s):  
Julian Wampfler ◽  
Elena A. Federzoni ◽  
Bruce E. Torbett ◽  
Martin F. Fey ◽  
Mario P. Tschan
Leukemia ◽  
2021 ◽  
Author(s):  
Xiao Fang ◽  
Song’en Xu ◽  
Yiyue Zhang ◽  
Jin Xu ◽  
Zhibin Huang ◽  
...  

AbstractASXL1 is one of the most frequently mutated genes in malignant myeloid diseases. In patients with myeloid malignancies, ASXL1 mutations are usually heterozygous frameshift or nonsense mutations leading to C-terminal truncation. Current disease models have predominantly total loss of ASXL1 or overexpressed C-terminal truncations. These models cannot fully recapitulate leukemogenesis and disease progression. We generated an endogenous C-terminal-truncated Asxl1 mutant in zebrafish that mimics human myeloid malignancies. At the embryonic stage, neutrophil differentiation was explicitly blocked. At 6 months, mutants initially exhibited a myelodysplastic syndrome-like phenotype with neutrophilic dysplasia. At 1 year, about 13% of mutants further acquired the phenotype of monocytosis, which mimics chronic myelomonocytic leukemia, or increased progenitors, which mimics acute myeloid leukemia. These features are comparable to myeloid malignancy progression in humans. Furthermore, transcriptome analysis, inhibitor treatment, and rescue assays indicated that asxl1-induced neutrophilic dysplasia was associated with reduced expression of bmi1a, a subunit of polycomb repressive complex 1 and a reported myeloid leukemia-associated gene. Our model demonstrated that neutrophilic dysplasia caused by asxl1 mutation is a foundation for the progression of myeloid malignancies, and illustrated a possible effect of the Asxl1-Bmi1a axis on regulating neutrophil development.


Blood ◽  
2003 ◽  
Vol 101 (2) ◽  
pp. 711-721 ◽  
Author(s):  
Laura L. W. Cooling ◽  
De Sheng Zhang ◽  
Stanley J. Naides ◽  
Theodore A. W. Koerner

Glycosphingolipids (GSLs) are complex macromolecules on cell membranes that have been shown to play a role in neutrophil differentiation, activation, phagocytosis, and adhesion to both microorganisms and vascular endothelium. Because GSLs are often cryptic antigens on cell membranes, little is known regarding GSL expression in early myelopoiesis. To study the latter, myeloblasts were collected from patients with acute nonlymphocytic leukemia (ANLL) who required therapeutic leukocytopheresis for hyperleukocytosis. The neutral GSLs were isolated and identified by high-performance thin-layer chromatography (HPTLC), HPTLC immunostaining, gas chromatography, nuclear magnetic resonance, and fast atom bombardment–mass spectrometry. Like mature peripheral blood neutrophils, myeloblasts expressed glucosylceramide, lactosylceramide, and the neolacto-family GSLs, lactotriaosylceramide and neolactotetraosylceramide. Unlike neutrophils and chronic myeloid leukemia, most ANLL samples also expressed the globo-series GSLs, globotriaosylceramide and globotetraosylceramide. Globo GSL expression was strongly associated with a myeloblastic (ANLL M0-M2) and monoblastic phenotype (M5). A weak association was also noted with expression of either lymphoid (P < .10) or early hematopoietic markers (terminal deoxynucleotidyl transferase [TdT], CD34; P < .10). Globo-positive ANLL samples bound both shiga toxin and parvovirus B19 on HPTLC immunostaining. Based on these findings, we propose that neolacto and globo GSLs are expressed during early myeloid differentiation. Globotriaosylceramide expression on myeloblasts, and possibly myeloid stem cells, may have important implications for the use of shiga toxin as an ex vivo purging agent in autologous stem cell transplantation. Expression of globotetraosylceramide, the parvovirus B19 receptor, on myeloblasts may also explain the association between B19 infection, aplastic anemia, and chronic neutropenia of childhood.


Hematology ◽  
2009 ◽  
Vol 2009 (1) ◽  
pp. 344-350 ◽  
Author(s):  
Christoph Klein

Abstract Congenital neutropenia comprises a variety of genetically heterogeneous phenotypic traits. Molecular elucidation of the underlying genetic defects has yielded important insights into the physiology of neutrophil differentiation and function. Non-syndromic variants of congenital neutropenia are caused by mutations in ELA2, HAX1, GFI1, or WAS. Syndromic variants of congenital neutropenia may be due to mutations in genes controlling glucose metabolism (SLC37A4, G6PC3) or lysosomal function (LYST, RAB27A, ROBLD3/p14, AP3B1, VPS13B). Furthermore, defects in genes encoding ribosomal proteins (SBDS, RMRP) and mitochondrial proteins (AK2, TAZ) are associated with congenital neutropenia syndromes. Despite remarkable progress in the field, many patients with congenital neutropenia cannot yet definitively be classified by genetic terms. This review addresses diagnostic and therapeutic aspects of congenital neutropenia and covers recent molecular and pathophysiological insights of selected congenital neutropenia syndromes.


Blood ◽  
2006 ◽  
Vol 107 (8) ◽  
pp. 3330-3338 ◽  
Author(s):  
Beatrice U. Mueller ◽  
Thomas Pabst ◽  
José Fos ◽  
Vibor Petkovic ◽  
Martin F. Fey ◽  
...  

Abstract Tightly regulated expression of the transcription factor PU.1 is crucial for normal hematopoiesis. PU.1 knockdown mice develop acute myeloid leukemia (AML), and PU.1 mutations have been observed in some populations of patients with AML. Here we found that conditional expression of promyelocytic leukemia-retinoic acid receptor α (PML-RARA), the protein encoded by the t(15;17) translocation found in acute promyelocytic leukemia (APL), suppressed PU.1 expression, while treatment of APL cell lines and primary cells with all-trans retinoic acid (ATRA) restored PU.1 expression and induced neutrophil differentiation. ATRA-induced activation was mediated by a region in the PU.1 promoter to which CEBPB and OCT-1 binding were induced. Finally, conditional expression of PU.1 in human APL cells was sufficient to trigger neutrophil differentiation, whereas reduction of PU.1 by small interfering RNA (siRNA) blocked ATRA-induced neutrophil differentiation. This is the first report to show that PU.1 is suppressed in acute promyelocytic leukemia, and that ATRA restores PU.1 expression in cells harboring t(15;17).


Immunity ◽  
2017 ◽  
Vol 47 (3) ◽  
pp. 466-480.e5 ◽  
Author(s):  
Thomas Riffelmacher ◽  
Alexander Clarke ◽  
Felix C. Richter ◽  
Amanda Stranks ◽  
Sumeet Pandey ◽  
...  

2008 ◽  
Vol 3 ◽  
pp. BMI.S600 ◽  
Author(s):  
S. Chiosea ◽  
M. Acquafondata ◽  
J. Luo ◽  
SF. Kuan ◽  
RR. Seethala

Differential microRNA expression in colon adenocarcinoma (CA) was previously reported. MicroRNA biogenesis and function requires a set of proteins designated as the microRNA machinery, which includes DICER1 and PRKRA. Loss of heterozygosity at 14q32.13 DICER1 locus was detected in up to 60% of CA cases. The in silico gene array analysis of CA showed down-regulation of DICER1 and an up-regulation of PRKRA. Immunohistochemically, DICER1 expression was abnormal in 65% of CA (95 of 147 cases). PRKRA was deregulated in 70% of CA (32 of 46 cases). Expression of DICER1 and PRKRA was correlated with clinicopathologic features of CA. DICER1 up-regulation was seen more commonly in women. Only 10 of 46 cases immunostained for both DICER1 and PRKRA showed normal levels of both DICER1 and PRKRA. Microsatellite status of 32 cases was determined. Microsatellite instable cases showed DICER1 up-regulation more commonly when compared to microsatellite stable cases; however, this trend was not statistically significant. Abnormal DICER1 and/or PRKRA expression might explain the observed changes in microRNA profile. The status of the endogenous DICER1 and PRKRA in CA may help to predict the response to future RNA interference-based therapy.


2018 ◽  
Vol 47 (5) ◽  
pp. 1936-1950 ◽  
Author(s):  
Ayako Tanimura ◽  
Keiko Miyoshi ◽  
Taigo Horiguchi ◽  
Hiroko Hagita ◽  
Koichi Fujisawa ◽  
...  

Background/Aims: Endoplasmic reticulum (ER) stress and unfolded protein response (UPR) are involved in hematopoietic differentiation. However, the mechanistic linkage between ER stress/UPR and hematopoietic differentiation remains unclear. Methods: We used bipotent HL-60 cells as an in vitro hematopoietic differentiation system to investigate the role of ER stress and UPR activity in neutrophil and macrophage differentiation. Results: The in vitro differentiation analysis revealed that ER stress decreased during both neutrophil and macrophage differentiations, and the activities of PERK and ATF6 were decreased and that of IRE1α was increased during neutrophil differentiation in a stage-specific manner. By contrast, the activities of ATF6 and ATF4 decreased during macrophage differentiation. When the cells were treated with oligomycin, the expression of CD11b, a myelocytic differentiation marker, and morphological differentiation were suppressed, and XBP-1 activation was inhibited during neutrophil differentiation, whereas CD11b expression was maintained, and morphological differentiation was not obviously affected during macrophage differentiation. Conclusion: In this study, we demonstrated that neutrophil differentiation is regulated by ER stress/UPR that is supported by mitochondrial ATP supply, in which IRE1α-XBP1 activation is essential. Our findings provide the evidence that mitochondrial energy metabolism may play a critical role in neutrophil differentiation.


2014 ◽  
Author(s):  
Mario P. Tschan ◽  
Aladin Haimovici ◽  
Daniel Brigger ◽  
Anna M. Schläfli ◽  
Deborah Shan ◽  
...  

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