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Genes, Chromosomes & Cancer Oct 2023The promyelocytic leukemia-retinoic acid receptor-α (PML::RARA) fusion is the hallmark of acute promyelocytic leukemia (APL) and is observed in over 95% of APL cases....
The promyelocytic leukemia-retinoic acid receptor-α (PML::RARA) fusion is the hallmark of acute promyelocytic leukemia (APL) and is observed in over 95% of APL cases. RARA and homologous receptors RARB and RARG are occasionally fused to other gene partners, which differentially affect sensitivity to targeted therapies. Most APLs without RARA fusions have rearrangements involving RARG or RARB, both of which frequently show resistance to all-trans-retinoic acid (ATRA) and/or multiagent chemotherapy for acute myeloid leukemia (AML). We present a 13-year-old male diagnosed with variant APL with a novel FNDC3B::RARB in-frame fusion that showed no response to ATRA but responded well to conventional AML therapy. While FNDC3B has been identified as a rare RARA translocation partner in ATRA-sensitive variant APL, it has never been reported as a fusion partner with RARB and it is only the second known fusion partner with RARB in variant APL. We also show that this novel fusion confers an RNA expression signature that is similar to APL, despite clinical resistance to ATRA monotherapy.
Topics: Male; Humans; Adolescent; Leukemia, Promyelocytic, Acute; Translocation, Genetic; Tretinoin; Leukemia, Myeloid, Acute; Retinoic Acid Receptor alpha; Genomics; Oncogene Proteins, Fusion; Fibronectins
PubMed: 37283355
DOI: 10.1002/gcc.23180 -
PLoS Biology Nov 2023Throughout life, hematopoietic stem cells (HSCs), residing in bone marrow (BM), continuously regenerate erythroid/megakaryocytic, myeloid, and lymphoid cell lineages....
The miR-221/222 cluster regulates hematopoietic stem cell quiescence and multipotency by suppressing both Fos/AP-1/IEG pathway activation and stress-like differentiation to granulocytes.
Throughout life, hematopoietic stem cells (HSCs), residing in bone marrow (BM), continuously regenerate erythroid/megakaryocytic, myeloid, and lymphoid cell lineages. This steady-state hematopoiesis from HSC and multipotent progenitors (MPPs) in BM can be perturbed by stress. The molecular controls of how stress can impact hematopoietic output remain poorly understood. MicroRNAs (miRNAs) as posttranscriptional regulators of gene expression have been found to control various functions in hematopoiesis. We find that the miR-221/222 cluster, which is expressed in HSC and in MPPs differentiating from them, perturbs steady-state hematopoiesis in ways comparable to stress. We compare pool sizes and single-cell transcriptomes of HSC and MPPs in unperturbed or stress-perturbed, miR-221/222-proficient or miR-221/222-deficient states. MiR-221/222 deficiency in hematopoietic cells was induced in C57BL/6J mice by conditional vav-cre-mediated deletion of the floxed miR-221/222 gene cluster. Social stress as well as miR-221/222 deficiency, alone or in combination, reduced HSC pools 3-fold and increased MPPs 1.5-fold. It also enhanced granulopoisis in the spleen. Furthermore, combined stress and miR-221/222 deficiency increased the erythroid/myeloid/granulocytic precursor pools in BM. Differential expression analyses of single-cell RNAseq transcriptomes of unperturbed and stressed, proficient HSC and MPPs detected more than 80 genes, selectively up-regulated in stressed cells, among them immediate early genes (IEGs). The same differential single-cell transcriptome analyses of unperturbed, miR-221/222-proficient with deficient HSC and MPPs identified Fos, Jun, JunB, Klf6, Nr4a1, Ier2, Zfp36-all IEGs-as well as CD74 and Ly6a as potential miRNA targets. Three of them, Klf6, Nr4a1, and Zfp36, have previously been found to influence myelogranulopoiesis. Together with increased levels of Jun, Fos forms increased amounts of the heterodimeric activator protein-1 (AP-1), which is known to control the expression of the selectively up-regulated expression of the IEGs. The comparisons of single-cell mRNA-deep sequencing analyses of socially stressed with miR-221/222-deficient HSC identify 5 of the 7 Fos/AP-1-controlled IEGs, Ier2, Jun, Junb, Klf6, and Zfp36, as common activators of HSC from quiescence. Combined with stress, miR-221/222 deficiency enhanced the Fos/AP-1/IEG pathway, extended it to MPPs, and increased the number of granulocyte precursors in BM, inducing selective up-regulation of genes encoding heat shock proteins Hspa5 and Hspa8, tubulin-cytoskeleton-organizing proteins Tuba1b, Tubb 4b and 5, and chromatin remodeling proteins H3f3b, H2afx, H2afz, and Hmgb2. Up-regulated in HSC, MPP1, and/or MPP2, they appear as potential regulators of stress-induced, miR-221/222-dependent increased granulocyte differentiation. Finally, stress by serial transplantations of miR-221/222-deficient HSC selectively exhausted their lymphoid differentiation capacities, while retaining their ability to home to BM and to differentiate to granulocytes. Thus, miR-221/222 maintains HSC quiescence and multipotency by suppressing Fos/AP-1/IEG-mediated activation and by suppressing enhanced stress-like differentiation to granulocytes. Since miR-221/222 is also expressed in human HSC, controlled induction of miR-221/222 in HSC should improve BM transplantations.
Topics: Animals; Humans; Mice; Cell Differentiation; Granulocytes; Hematopoietic Stem Cells; Mice, Inbred C57BL; MicroRNAs; Transcription Factor AP-1
PubMed: 37983263
DOI: 10.1371/journal.pbio.3002015 -
EMBO Molecular Medicine Jun 2024Clear-cell renal cell carcinoma (ccRCC), the major subtype of RCC, is frequently diagnosed at late/metastatic stage with 13% 5-year disease-free survival. Functional...
Clear-cell renal cell carcinoma (ccRCC), the major subtype of RCC, is frequently diagnosed at late/metastatic stage with 13% 5-year disease-free survival. Functional inactivation of the wild-type p53 protein is implicated in ccRCC therapy resistance, but the detailed mechanisms of p53 malfunction are still poorly characterized. Thus, a better understanding of the mechanisms of disease progression and therapy resistance is required. Here, we report a novel ccRCC dependence on the promyelocytic leukemia (PML) protein. We show that PML is overexpressed in ccRCC and that PML depletion inhibits cell proliferation and relieves pathologic features of anaplastic disease in vivo. Mechanistically, PML loss unleashed p53-dependent cellular senescence thus depicting a novel regulatory axis to limit p53 activity and senescence in ccRCC. Treatment with the FDA-approved PML inhibitor arsenic trioxide induced PML degradation and p53 accumulation and inhibited ccRCC expansion in vitro and in vivo. Therefore, by defining non-oncogene addiction to the PML gene, our work uncovers a novel ccRCC vulnerability and lays the foundation for repurposing an available pharmacological intervention to restore p53 function and chemosensitivity.
Topics: Promyelocytic Leukemia Protein; Carcinoma, Renal Cell; Humans; Tumor Suppressor Protein p53; Cellular Senescence; Animals; Kidney Neoplasms; Cell Line, Tumor; Cell Proliferation; Arsenic Trioxide; Mice
PubMed: 38730056
DOI: 10.1038/s44321-024-00077-3 -
International Journal of Biological... Dec 2023For the potential health benefits and nutritional value, polyphenols are one of the secondary metabolites of plants that have received extensive research. It has... (Review)
Review
Protective effects of macromolecular polyphenols, metals (zinc, selenium, and copper) - Polyphenol complexes, and different organs with an emphasis on arsenic poisoning: A review.
For the potential health benefits and nutritional value, polyphenols are one of the secondary metabolites of plants that have received extensive research. It has anti-inflammatory and cytotoxicity-reducing properties in addition to a high antioxidant content. Macromolecular polyphenols and polysaccharides are biologically active natural polymers with antioxidant and anti-inflammatory potential. Arsenic is an ecologically toxic metalloid. Arsenic in drinking water is the most common way people come into contact with this metalloid. While arsenic is known to cause cancer, it is also used to treat acute promyelocytic leukemia (APL). The treatment's effectiveness is hampered by the adverse effects it can cause on the body. Oxidative stress, inflammation, and the inability to regulate cell death cause the most adverse effects. Polyphenols and other macromolecules like polysaccharides act as neuroprotectants by mitigating free radical damage, inhibiting nitric oxide (NO) production, lowering A42 fibril formation, boosting antioxidant levels, and controlling apoptosis and inflammation. To prevent the harmful effects of toxins, polyphenols and pectin lower oxidative stress, boost antioxidant levels, improve mitochondrial function, control apoptosis, and suppress inflammation. Therefore, it prevents damage to the heart, liver, kidneys, and reproductive system. This review aims to identify the effects of the polyphenols in conjugation with polysaccharides as an ameliorative strategy for arsenic-induced toxicity in various organs.
Topics: Humans; Antioxidants; Selenium; Arsenic; Copper; Arsenic Poisoning; Polyphenols; Zinc; Oxidative Stress; Inflammation; Pectins; Anti-Inflammatory Agents
PubMed: 37673136
DOI: 10.1016/j.ijbiomac.2023.126715 -
PloS One 2023In myelodysplastic syndromes (MDS), neoplastic myeloblast (CD34+CD13+CD33+ cells) numbers often increase over time, leading to secondary acute myeloid leukemia (AML). In...
OBJECTIVES
In myelodysplastic syndromes (MDS), neoplastic myeloblast (CD34+CD13+CD33+ cells) numbers often increase over time, leading to secondary acute myeloid leukemia (AML). In recent studies, blasts in some MDS patients have been found to express a megakaryocyte-lineage molecule, CD41, and such patients show extremely poor prognosis. This is the first study to evaluate whether myeloblasts transition to CD41+ blasts over time and to investigate the detailed immunophenotypic features of CD41+ blasts in MDS.
METHODS
We performed a retrospective cohort study, in which time-dependent changes in blast immunophenotypes were analyzed using multidimensional flow cytometry (MDF) in 74 patients with MDS and AML (which progressed from MDS).
RESULTS
CD41+ blasts (at least 20% of CD34+ blasts expressing CD41) were detected in 12 patients. In five of these 12 patients, blasts were CD41+ from the first MDF analysis. In the other seven patients, myeloblasts (CD34+CD33+CD41- cells) transitioned to megakaryoblasts (CD34+CD41+ cells) over time, which was often accompanied by disease progression (including leukemic transformation). These CD41+ patients were more frequently observed among patients with monosomal and complex karyotypes. CD41+ blasts were negative for the erythroid antigen, CD235a, and positive for CD33 in all cases, but CD33 expression levels were lower in three cases when compared with CD34+CD41- blasts. Among the five CD41+ patients who underwent extensive immunophenotyping, CD41+ blasts all expressed CD61, but two cases had reduced CD42b expression, three had reduced/absent CD13 expression, and three also expressed CD7.
CONCLUSIONS
Myeloblasts become megakaryoblastic over time in some MDS patients, and examining the megakaryocyte lineage (not only as a diagnostic work-up but also as follow-up) is needed to detect CD41+ MDS. The immunophenotypic features revealed in this study may have diagnostic relevance for CD41+ MDS patients.
Topics: Humans; Granulocyte Precursor Cells; Immunophenotyping; Megakaryocyte Progenitor Cells; Retrospective Studies; Antigens, CD34; Myelodysplastic Syndromes
PubMed: 37729123
DOI: 10.1371/journal.pone.0291662 -
Cureus Sep 2023In the last decade, advancements in understanding the genetic and molecular mechanisms of acute myeloid leukemia (AML) have significantly improved treatment options....
In the last decade, advancements in understanding the genetic and molecular mechanisms of acute myeloid leukemia (AML) have significantly improved treatment options. Techniques such as immunophenotyping, cytogenetics, and next-generation sequence (NGS) testing are now standard practices for patient assessments, allowing for personalized therapies based on individual patient needs. Our study aimed to evaluate the impact of cytogenetics and NGS on initial treatment decisions for AML at our institution. We analyzed the frequency of alternative therapy choices that could have been made with complete molecular and cytogenetic information and compared overall survival rates between patient groups. We also analyzed the turnaround time for result generation. Our retrospective study evaluated 39 AML patients treated at our university hospital from June 2020 to June 2022, excluding classic acute promyelocytic leukemia cases. Patients with incomplete data or concurrent hematological malignancies were excluded. We collected data on admission blood counts, European LeukemiaNet (ELN) risk stratification, Charlson score, treatment type, and timing of cytogenetics and NGS results. Patients were categorized into 'standard' or 'other therapy' groups based on their molecular and cytogenetic profiles in accordance with NCCN guidelines. Our main goal was to determine how often NGS and cytogenetics results could have influenced induction therapy choices. Secondary objectives included comparing overall survival rates and analyzing report turnaround times for NGS and cytogenetics. Our study found that out of the 39 AML patients, 17 were in the "standard" group, and 22 were in the "other therapy" group. The standard group had an average age of 62.59 years, an average time to chemotherapy initiation of 8.29 days, and an overall survival (OS) rate of 428.12 days. The other therapy group had an average age of 61.86 years, an average time to chemotherapy initiation of six days, and an OS rate of 258.64 days. There was a significant difference in survival rates between the two groups (p=0.009). According to the ELN stratification, the standard group had 11 patients at intermediate risk and six at adverse risk. In contrast, the other therapy group had seven at intermediate risk, four at good risk, and 11 at adverse risk. NGS revealed mutations in 58.97% of patients. Our study suggests that almost half of the patients could have been treated differently if complete molecular and cytogenetic information had been available before therapy initiation, highlighting the potential for more personalized treatments. Additionally, our results showed significant differences in overall survival rates between standard treatment and alternative therapy groups. Our findings emphasize the importance of timely NGS and cytogenetics result generation, guiding institutions to allocate resources for effective patient care.
PubMed: 37885525
DOI: 10.7759/cureus.45917 -
Nucleic Acids Research Nov 2023The promyelocytic leukemia (PML) protein organizes nuclear aggregates known as PML nuclear bodies (PML-NBs), where many transcription factors localize to be regulated....
The promyelocytic leukemia (PML) protein organizes nuclear aggregates known as PML nuclear bodies (PML-NBs), where many transcription factors localize to be regulated. In addition, associations of PML and PML-NBs with chromatin are described in various cell types, further implicating PML in transcriptional regulation. However, a complete understanding of the functional consequences of PML association to DNA in cellular contexts where it promotes relevant phenotypes is still lacking. We examined PML chromatin association in triple-negative breast cancer (TNBC) cell lines, where it exerts important oncogenic functions. We find that PML associates discontinuously with large heterochromatic PML-associated domains (PADs) that contain discrete gene-rich euchromatic sub-domains locally depleted of PML. PML promotes heterochromatic organization in PADs and expression of pro-metastatic genes embedded in these sub-domains. Importantly, this occurs outside PML-NBs, suggesting that nucleoplasmic PML exerts a relevant gene regulatory function. We also find that PML plays indirect regulatory roles in TNBC cells by promoting the expression of pro-metastatic genes outside PADs. Our findings suggest that PML is an important transcriptional regulator of pro-oncogenic metagenes in TNBC cells, via transcriptional regulation and epigenetic organization of heterochromatin domains that embed regions of local transcriptional activity.
Topics: Humans; Cell Nucleus; Chromatin; Epigenesis, Genetic; Nuclear Proteins; Promyelocytic Leukemia Protein; Transcription Factors; Triple Negative Breast Neoplasms; Cell Line, Tumor
PubMed: 37823593
DOI: 10.1093/nar/gkad819 -
BioRxiv : the Preprint Server For... Nov 2023The development of a telomere maintenance mechanism is essential for immortalization in human cancer. While most cancers elongate their telomeres by expression of...
The development of a telomere maintenance mechanism is essential for immortalization in human cancer. While most cancers elongate their telomeres by expression of telomerase, 10-15% of human cancers use a pathway known as alternative lengthening of telomeres (ALT). In this work, we developed a genetically engineered primary mouse model of sarcoma in CAST/EiJ mice which displays multiple molecular features of ALT activation after CRISPR/Cas9 introduction of oncogenic and loss of function mutations of and . In this model, we demonstrate that the loss of contributes to the development of ALT in an autochthonous tumor, and this process occurs independently of telomerase function by variation of mTR alleles. Furthermore, we find that telomere shortening from the loss of telomerase leads to higher chromosomal instability while loss of and activation of ALT lead to an increase in telomeric instability, telomere sister chromatid exchange, c-circle production, and formation of ALT-associated promyelocytic leukemia bodies (APBs). The development of this primary mouse model of ALT could enable future investigations into therapeutic vulnerabilities of ALT activation and its mechanism of action.
PubMed: 37986934
DOI: 10.1101/2023.11.06.565874 -
The Journal of Investigative Dermatology Jul 2024The pathological hallmark of psoriasis is the infiltration of neutrophils into the skin. Some neutrophil-derived microRNAs (miRNAs) serve as biomarkers for various...
The pathological hallmark of psoriasis is the infiltration of neutrophils into the skin. Some neutrophil-derived microRNAs (miRNAs) serve as biomarkers for various diseases, but none have been reported for psoriasis. In this study, we investigated the involvement of miRNAs released from neutrophils in psoriasis pathogenesis. We compared the expression of miRNAs in the sera of patients with psoriasis with that in healthy individuals and found that the expression of 2 miRNAs-miR-223 and miR-1290-was significantly upregulated in the sera of patients with psoriasis. The serum levels of these miRNAs positively correlated with the PASI and CRP levels. We used all-trans retinoic acid to induce the differentiation of human promyelocytic leukemia HL-60 cells into neutrophil-like cells and found that the release of both miRNAs increased during differentiation. Furthermore, the release of miR-1290 was increased by TNF-α in neutrophil-like cells and human neutrophils. Treatment with the miR-1290 precursor promoted the proliferation of human keratinocytes, increased the proportion of S-phase cells, and upregulated the phosphorylation of extracellular signal-regulated kinase 1/2. These results suggest that miR-1290 plays a vital role in regulating neutrophil differentiation and keratinocyte proliferation and could be a serum marker of psoriasis severity.
Topics: Humans; Psoriasis; MicroRNAs; Keratinocytes; Cell Proliferation; Neutrophils; Male; Female; Cell Differentiation; HL-60 Cells; Middle Aged; Adult; Biomarkers; Up-Regulation; Case-Control Studies; Tumor Necrosis Factor-alpha
PubMed: 38157932
DOI: 10.1016/j.jid.2023.10.042 -
Cell Communication and Signaling : CCS Oct 2023Neutrophils depend heavily on glycolysis for energy production under normal conditions. In contrast, neutrophils require energy supplied by mitochondrial oxidative...
LRRK2 is involved in the chemotaxis of neutrophils and differentiated HL-60 cells, and the inhibition of LRRK2 kinase activity increases fMLP-induced chemotactic activity.
BACKGROUND
Neutrophils depend heavily on glycolysis for energy production under normal conditions. In contrast, neutrophils require energy supplied by mitochondrial oxidative phosphorylation (OXPHOS) during chemotaxis. However, the mechanism by which the energy supply changes from glycolysis to OXPHOS remains unknown. Leucine-rich repeat kinase 2 (LRRK2) is partially present in the outer mitochondrial membrane fraction. Lrrk2-deficient cells show mitochondrial fragmentation and reduced OXPHOS activity. We have previously reported that mitofusin (MFN) 2 is involved in chemotaxis and OXPHOS activation upon chemoattractant N-formyl-Met-Leu-Phe (fMLP) stimulation in differentiated HL-60 (dHL-60) cells. It has been previously reported that LRRK2 binds to MFN2 and partially colocalizes with MFN2 at the mitochondrial membranes. This study investigated the involvement of LRRK2 in chemotaxis and MFN2 activation in neutrophils and dHL-60 cells.
METHODS
Lrrk2 knockout neutrophils and Lrrk2 knockdown dHL-60 cells were used to examine the possible involvement of LRRK2 in chemotaxis. Lrrk2 knockdown dHL-60 cells were used a tetracycline-inducible small hairpin RNA (shRNA) system to minimize the effects of LRRK2 knockdown during cell culture. The relationship between LRRK2 and MFN2 was investigated by measuring the GTP-binding activity of MFN2 in Lrrk2 knockdown dHL-60 cells. The effects of LRRK2 kinase activity on chemotaxis were examined using the LRRK2 kinase inhibitor MLi-2.
RESULTS
fMLP-induced chemotactic activity was reduced in Lrrk2 knockout neutrophils in vitro and in vivo. Lrrk2 knockdown in dHL-60 cells expressing Lrrk2 shRNA also reduced fMLP-induced chemotactic activity. Lrrk2 knockdown dHL-60 cells showed reduced OXPHOS activity and suppressed mitochondrial morphological change, similar to Mfn2 knockdown dHL-60 cells. The amount of LRRK2 in the mitochondrial fraction and the GTP-binding activity of MFN2 increased upon fMLP stimulation, and the MFN2 GTP-binding activity was suppressed in Lrrk2 knockdown dHL-60 cells. Furthermore, the kinase activity of LRRK2 and Ser935 phosphorylation of LRRK2 were reduced upon fMLP stimulation, and LRRK2 kinase inhibition by MLi-2 increased the migration to fMLP.
CONCLUSIONS
LRRK2 is involved in neutrophil chemotaxis and the GTP-binding activity of MFN2 upon fMLP stimulation. On the other hand, the kinase activity of LRRK2 shows a negative regulatory effect on fMLP-induced chemotactic activity in dHL-60 cells. Video Abstract.
Topics: Humans; Chemotaxis; Neutrophils; HL-60 Cells; Oxidative Phosphorylation; RNA, Small Interfering; Guanosine Triphosphate; Leucine-Rich Repeat Serine-Threonine Protein Kinase-2
PubMed: 37904222
DOI: 10.1186/s12964-023-01305-y