Single-cell sequencing unveils T-cell characteristic in acute myeloid leukemia.

Acute myeloid leukemia (AML) presents as a remarkably heterogeneous disease, and the intricate role of various T cell subtypes, including T helper (Th) cells and regulatory T (Treg) cells, in immune dysregulation and the promotion of leukemia cell proliferation and survival is not yet fully understood. In this study, we conducted a comparative analysis of transcriptome profiles in T cells derived from bone marrow samples of three leukemia patients, both before and after treatment, as well as from a relapse sample. This analysis was facilitated through the utilization of single-cell RNA sequencing. The T cell population was subcategorized into CD4 + T cells and CD8 + T cells. Intriguingly, the composition of CD8 + T cells exhibited a relatively stable pattern before and after treatment, while a substantial difference in composition was observed in CD4 + T cells, notably in Th17 and Treg cell populations. Pseudotime trajectory analysis of CD4 + T cell clusters provided further insights into the augmented transition between Th17-like and Treg cells in AML. This transition was characterized by changes in the expression of key genes, including STAT3, CCR6, IL23R, FOXP3, and CTLA4, along their developmental path. An increased cell-to-cell interaction between AML blast cells and all types of T cells appeared to contribute to the restoration of normal T cell proportions. Notably, the LGALS9-CD45 and LGALS9-CD44 pathways emerged as pivotal interactions between blast cells and Treg cells. Our findings unveil an imbalanced differentiation pattern in CD4 + T cells and elucidate the immunosuppressive profiles linked to leukemia cells, thereby enhancing our understanding of CD4 + T cell functionality in the context of AML.

Ectopic viral integration Site-1 oncogene promotes NRAS pathway through epigenetic silencing of microRNA-124 in acute myeloid leukemia.

BACKGROUND: Acute myeloid leukemia (AML) is an aggressive hematological malignancy characterized by genetic mutations that promote proliferation of myeloid progenitors and prevent their differentiation. Over-expression of Ectopic Viral Integration site-1(EVI-1) is related to the poor prognosis in myeloid leukemia, but the underlying mechanism remains unclear. METHODS: Using qRT-PCR and western blotting, we quantified expressions of EVI-1, NRAS and ERK/p-ERK in leukemia cell lines and PBMCs. Using WTS-8 and cell cycle analysis, we further investigated whether downregulation of EVI-1 by siRNA can inhibit cell proliferation. Microscopic observation of peripheral blood cells from EVI-1 transgenic zebrafish and WT control were analyzed by Wright Giemsa staining. Using miR-seq, qPCR, dual-luciferase reporter and coimmunoprecipitation assays, we revealed the relationship between EVI-1, miR-124 and NRAS. RESULTS: EVI-1 was highly expressed in both primary AML and leukemia cell lines (THP-1 and K562). In a transgenic zebrafish model, EVI-1 mediated higher mortality and induced immature hematopoietic cells in the blood circulation, suggesting its oncogenic role. Furthermore, our results suggested that EVI-1 upregulated NRAS expression, thereby activating the RAS/ERK pathway through epigenetic silencing of a potent NRAS suppressor, miR-124. In this study, we found that EVI1 physically interacts with Dnmt3a to form a protein complex that targets and binds to regulatory elements of miR-124. CONCLUSIONS: Overall, the current findings demonstrate that EVI-1 overexpression converges on the regulation of miR-124 promoter methylation and activation of the RAS/ERK pathway in AML carcinogenesis, and suggest EVI-1 and/or miR-124 as therapeutic targets for this dismal disease.

Homoharringtonine Synergized with Gilteritinib Results in the Downregulation of Myeloid Cell Leukemia-1 by Upregulating UBE2L6 in FLT3-ITD-Mutant Acute Myeloid (Leukemia) Cell Lines.

FMS-like tyrosine kinase 3 (FLT3) mutant acute myeloid leukemia (AML) occurs in approximately 30% of all AML patients and still has a poor prognosis. This study is directed to investigate gilteritinib in combination with homoharringtonine (HHT) on FLT3-ITD-mutant AML cell lines. In our study, we found that cell proliferation was dramatically suppressed by the combination of gilteritinib and HHT. This combination therapy decreased the mitochondrial membrane potential, finally inducing apoptosis. We demonstrated that gilteritinib downregulated the expression of FLT3 and downstream signaling, further decreased the mRNA level of myeloid cell leukemia-1 (Mcl-1). HHT and combination therapy could upregulate UBE2L6, which induced the degradation of Mcl-1 via ubiquitin-proteasome system. Knockdown of UBE2L6 could protect Mcl-1 from deprivation through the ubiquitin-proteasome system. These findings may provide a novel theoretical basis for the treatment of AML patients with FLT3-ITD mutations.

Serum Calcium Levels and Parkinson's Disease: A Mendelian Randomization Study.

BACKGROUND: Though increasing epidemiological studies have evaluated the correlation between serum calcium contents and Parkinson's disease (PD), the results are inconsistent. At present, whether there is a causal association between serum calcium content and PD remains undetermined. OBJECTIVE AND METHODS: This study was designed to explore the relationship between increased serum calcium contents and PD risk. In this present study, a Mendelian randomization trial was carried out using a large-scale serum calcium genome-wide association study (GWAS) dataset (N = 61,079, Europeans) and a large-scale PD GWAS dataset (N = 8,477, Europeans including 4,238 PD patients and 4,239 controls). Here, a total of four Mendelian randomization methods comprising weighted median, inverse-variance weighted meta-analysis (IVW), MR-Egger, and MR-PRESSO were used. RESULTS: Our data concluded that genetically higher serum calcium contents were not significantly related to PD. CONCLUSION: In conclusion, we provided genetic evidence that there was no direct causal relationship between serum calcium contents and PD. Hence, calcium supplementation may not result in reduced PD risk.

Arsenic trioxide potentiates Gilteritinib-induced apoptosis in FLT3-ITD positive leukemic cells via IRE1a-JNK-mediated endoplasmic reticulum stress.

BACKGROUND: Acute myeloid leukemia (AML) patients with FMS-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) have a high relapse rate and poor prognosis. This study aims to explore the underlying mechanism of combining Gilteritinib with ATO at low concentration in the treatment of FLT3-ITD positive leukemias. METHODS: We used both in vitro and in vivo studies to investigate the effects of combination of Gilteritinib with ATO at low concentration on FLT3-ITD positive leukemias, together with the underlying molecular mechanisms of these processes. RESULTS: Combination of Gilteritinib with ATO showed synergistic effects on inhibiting proliferation, increasing apoptosis and attenuating invasive ability in FLT3-ITD-mutated cells and reducing tumor growth in nude mice. Results of western blot indicated that Gilteritinib increased a 160KD form of FLT3 protein on the surface of cell membrane. Detection of endoplasmic reticulum stress marker protein revealed that IRE1a and its downstream signal phosphorylated JNK were suppressed in Gilteritinib-treated FLT3-ITD positive cells. The downregulation of IRE1a induced by Gilteritinib was reversed with addition of ATO. Knockdown of IRE1a diminished the combinatorial effects of Gilteritinib plus ATO treatment and combination of tunicamycin (an endoplasmic reticulum pathway activator) with Gilteritinib achieved the similar effect as treatment with Gilteritinib plus ATO. CONCLUSIONS: Thus, ATO at low concentration potentiates Gilteritinib-induced apoptosis in FLT3-ITD positive leukemic cells via IRE1a-JNK signal pathway, targeting IRE1a to cooperate with Gilteritinib may serve as a new theoretical basis on FLT3-ITD mutant AML treatment.

Modulation of FLT3 through decitabine-activated C/EBPa-PU.1 signal pathway in FLT3-ITD positive cells.

FMS-like tyrosine kinase 3 (FLT3)-mutant acute myeloid leukemia (AML) which occurs in approximately 30% of all AML patients still has a poor prognosis. This study aimed to examine the effect of decitabine (DAC) on FLT3-ITD positive AML. In our study, we found that expression of FLT3 and its downstream targets was decreased in FLT3-ITD mutant cell lines treated with DAC. DAC treatment could increase the percentage of apoptotic cells and CD11b positive cells tested by flow cytometry and upregulate the expression of cleaved caspase3, cleaved PARP, C/EBPa and PU.1 detected by western blot. To explore the effect of increased expression of PU.1 on FLT3 protein, we transiently transfected MOLM13 and MV4-11 cells with siRNA against PU.1 and a siRNA control. In both FLT3-ITD positive cells, the effect of DAC on downregulation of FLT3 was diminished in PU.1-konckdown MOLM13 and MV4-11 cells and there was a decrease of CD11b expression after PU.1 knockdown. Furthermore, the percentage of apoptotic cells was also decreased in PU.1-konckdown cells compared with siRNA control-expressing cells with the same dose of DAC. These findings indicated that DAC upregulated PU.1 to induce downregulation of FLT3 to trigger apoptosis. DAC was also found efficacious in mouse xenograft models of FLT3-ITD AML in our study. These findings may provide a novel theoretical basis for treatment of FLT3-ITD positive AML patients.

A Chiral and Polar Single-Molecule Magnet: Synthesis, Structure, and Tracking of Its Formation Using Mass Spectrometry.

The solvothermal reaction of cobalt(II) sulfate with S, S-1,2- bis(1-methyl-1 H-benzo[ d]imidazol-2-yl)ethane-1,2-diol, (H2L), neutralized with triethylamine (Et3N) in a mixture of methanol and water (2:1), resulted in triangular red crystals of [CoII7(L)3(SO4)3(OH)2(H2O)9]·4H2O·3CH3OH (Co7). It is formed of chiral and polar clusters crystallizing in the R3 space group. Co7 consists of apex-shared asymmetric dicubane units where all of the metals adopt an octahedral coordination and the three ligands wrap diagonally around the unit. One end of the cluster is bonded by six water molecules and the other end by three monodentate sulfates. The head-to-tail packing through extended H-bonds leads to polar chains. The ligand has lost two protons, adopts a cis-conformation, and is coordinated to five metals around the waist of the dicubane. Electrospray ionization mass spectrometry (ESI-MS) of solutions of the reaction as a function of time reveals the possible step-by-step assembly process of the cluster: the initial product [CoII(HL)(SO4)]2- combines with CoSO4, forming [CoII2(HL)(SO4)2]2-, and then, upon addition of Et3N, dimerizes through a [OH]- bridge to [CoII4(HL)2(OH)(CH3OH)2(SO4)3]- followed by capture of one Co2+ and one CoSO4 to form [CoII6(L)2(OH)(CH3O)(SO4)4]2- before eventually binding to CoL to form [CoII7(L)3(OH)2(SO4)4]2-. These results allow us to propose a possible process for the formation of Co7, which is a good example for chiral multidentate chelating ligand-controlled assembly of clusters. Magnetization measurements as a function of the temperature, field, and ac-frequency reveal ferromagnetic coupled moments and single-molecule magnetism (SMM).

Identification of Shared Genes Between Ischemic Stroke and Parkinson's Disease Using Genome-Wide Association Studies.

Ischemic stroke (IS) and Parkinson's disease (PD) are two neurological diseases that often strike individuals of advanced age. Although thought of as a disease of old age, PD can occur in younger patients. In many of these cases, genetic mutations underlie the disease. As with PD, stroke can also have a genetic component. Although many of the risk factors for IS are considered to be modifiable, a significant portion is not, suggesting that some of stroke risk factors may have a genetic origin. Large-scale genome-wide association studies (GWAS) have identified several IS and PD gene variants recently. Converging epidemiologic and pathological evidence suggests that IS and PD may be linked. However, it is still unclear whether these two conditions share a common mechanism. Here, we sought to determine the genetic mechanism underlying the possible association between IS and PD. We conducted a multi-step systemic analysis comprising (1) identification of IS and PD variants validated by known GWAS, (2) two separate gene-based tests using Versatile Gene-based Association Study 2 (VEGAS2) and PLINK, (3) a transcriptome-wide association study (TWAS), and (4) analyses of gene expression using an online tool in Gene Expression Omnibus. Our investigation revealed that IS and PD have in common five shared genes: GPX7, LBH, ZCCHC10, DENND2A, and NUDT14, which pass gene-based tests. Functionally, these genes are expressed differentially in IS and PD patients compared to neurologically healthy control subjects. This genetic overlap may provide clues on how IS and PD are linked mechanistically. This new genetic insight into these two diseases may be very valuable for narrowing the focus of future studies on the genetic basis of IS and PD and for developing novel therapies.

Shared genes between Alzheimer's disease and ischemic stroke.

AIMS: Although converging evidence from experimental and epidemiological studies indicates Alzheimer's disease (AD) and ischemic stroke (IS) are related, the genetic basis underlying their links is less well characterized. Traditional SNP-based genome-wide association studies (GWAS) have failed to uncover shared susceptibility variants of AD and IS. Therefore, this study was designed to investigate whether pleiotropic genes existed between AD and IS to account for their phenotypic association, although this was not reported in previous studies. METHODS: Taking advantage of large-scale GWAS summary statistics of AD (17,008 AD cases and 37,154 controls) and IS (10,307 IS cases and 19,326 controls), we performed gene-based analysis implemented in VEGAS2 and Fisher's meta-analysis of the set of overlapped genes of nominal significance in both diseases. Subsequently, gene expression analysis in AD- or IS-associated expression datasets was conducted to explore the transcriptional alterations of pleiotropic genes identified. RESULTS: 16 AD-IS pleiotropic genes surpassed the cutoff for Bonferroni-corrected significance. Notably, MS4A4A and TREM2, two established AD-susceptibility genes showed remarkable alterations in the spleens and brains afflicted by IS, respectively. Among the prioritized genes identified by virtue of literature-based knowledge, most are immune-relevant genes (EPHA1, MS4A4A, UBE2L3 and TREM2), implicating crucial roles of the immune system in the pathogenesis of AD and IS. CONCLUSIONS: The observation that AD and IS had shared disease-associated genes offered mechanistic insights into their common pathogenesis, predominantly involving the immune system. More importantly, our findings have important implications for future research directions, which are encouraged to verify the involvement of these candidates in AD and IS and interpret the exact molecular mechanisms of action.

EVI-1 modulates arsenic trioxide induced apoptosis through JNK signalling pathway in leukemia cells.

High expression of the oncogene ecotropic viral integration site-1 (EVI-1) is an independent negative prognostic indicator of survival in leukemia patients. This study aimed to examine the effects of arsenic trioxide (ATO) on EVI-1 in acute myeloid leukemia (AML). Mononuclear cells were isolated from the bone marrow and peripheral blood of AML patients and healthy donors. EVI-1 expression in hematopoietic cells was evaluated by RT-qPCR and Western blot analysis. EVI-1 was highly expressed in both primary AML and leukemia cell lines (THP-1 and K562). ATO down-regulated EVI-1 mRNA in zebrafish in vivo as well as in primary leukemia cells and THP-1 and K562 cells in vitro. Additionally, ATO treatment induced apoptosis, down-regulated both EVI-1 mRNA and oncoprotein expression, increased the expression of pro-apoptosis proteins, and decreased the expression of anti-apoptotic proteins in leukemia cells in vitro. EVI-1 expression in leukemia cells (THP-1 and K562) transduced with EVI-1 siRNA was significantly reduced. Silencing EVI-1 had a significant effect on the activation of the JNK pathway and the induction of leukemia cell apoptosis. ATO may downregulate EVI-1 mRNA and oncoprotein levels and block the inhibitory effects of EVI-1 on the JNK pathway, which activates the JNK apoptotic pathway, thereby leading to the apoptosis of EVI-1 in AML patients.

Shared Biological Pathways Between Alzheimer's Disease and Ischemic Stroke.

Alzheimer's disease (AD) and ischemic stroke (IS) are an immense socioeconomic burden worldwide. There is a possibility that shared genetic factors lead to their links at epidemiological and pathophysiological levels. Although recent genome-wide association studies (GWAS) have provided profound insights into the genetics of AD and IS, no shared genetic variants have been identified to date. This prompted us to initiate this study, which sought to identify shared pathways linking AD and IS. We took advantage of large-scale GWAS summary data of AD (17,008 AD cases and 37,154 controls) and IS (10,307 cases and 19,326 controls) to conduct pathway analyses using genetic pathways from multiple well-studied databases, including GO, KEGG, PANTHER, Reactome, and Wikipathways. Collectively, we discovered that AD and IS shared 179 GO categories (56 biological processes, 95 cellular components, and 28 molecular functions); and the following pathways: six KEGG pathways; two PANTHER pathways; four Reactome pathways; and one in Wikipathways pathway. The more fine-grained GO terms were mainly summarized into different functional categories: transcriptional and post-transcriptional regulation, synapse, endocytic membrane traffic through the endosomal system, signaling transduction, immune process, multi-organism process, protein catabolic metabolism, and cell adhesion. The shared pathways were roughly classified into three categories: immune system; cancer (NSCLC and glioma); and signal transduction pathways involving the cadherin signaling pathway, Wnt signaling pathway, G-protein signaling and downstream signaling mediated by phosphoinositides (PIPs). The majority of these common pathways linked to both AD and IS were supported by convincing evidence from the literature. In conclusion, our findings contribute to a better understanding of common biological mechanisms underlying AD and IS and serve as a guide to direct future research.

The reciprocal link between EVI1 and miRNAs in human malignancies.

Ecotropic virus integration site-1 (EVI1) is an oncogenic transcription factor which locus on chromosome 3(3q26.2). Alterations in EVI1 functions correspond with poor prognosis in different cancers, underscoring their status for the clinical cancer phenotype. MicroRNAs(MiR)are a class of small non-coding RNA sequences. They post-transcriptionally influence mRNA sequence through imperfect pairing with the 3'-UTR. Moreover, a growing body of studies showed that miRNAs could regulate initiation and progression of human malignancies. Current studies have been described that identifies numerous microRNAs that can be modulated by EVI1. Interestingly, the expression level of EVI1 can also be regulated by microRNAs, thus forming a reciprocal link. Recent understanding of the functional roles of EVI1, microRNAs, and their interactions in human cancers are summarized. This review will help to define a relationship between EVI1 and microRNAs in human malignancies and develop novel therapeutic strategies.

Upregulation of Microglial ZEB1 Ameliorates Brain Damage after Acute Ischemic Stroke.

Microglia are a key immune-competent cell type that respond to environmental and physiological changes during ischemic stroke. However, the molecular mechanisms controlling post-ischemic microglia activity are unclear. Understanding these mechanisms may ultimately reduce disease burden and allow the manipulation of microglia responses to shape the outcomes of stroke. Here, we report that, after experimentally induced stroke, ZEB1 is highly expressed in ipsilateral cerebral hemisphere, where it is upregulated mainly in microglia. Using a conditional transgenic mouse, we found that ZEB1 upregulation in microglia regulates immune responses in the CNS and alleviates brain injury after ischemic stroke. Our data indicate that ZEB1 overexpression mediates microglia responses and, in turn, inhibits the production of astrocytic CXCL1 through the TGF-ß1-dependent pathway. Reduced CXCL1 leads to a decline in neutrophil infiltration into the brain, thereby reducing CNS inflammation. Our results demonstrate the importance of ZEB1 in microglia-orchestrated neuroinflammation and suggest a potential means for reducing stroke-induced neurological injury.

Shared Gene Expression Between Multiple Sclerosis and Ischemic Stroke.

Patients with multiple sclerosis (MS) appear to have an increased risk of ischemic stroke (IS). Although MS and IS have very different phenotypes, gene-based and pathway-based analyses of large-scale genome-wide association studies (GWAS) have increasingly enhanced our understanding of these two diseases. Whether there are common molecular mechanisms connecting MS and IS is still unclear. Here, we describe the outcome of gene-based test and pathway-based analysis of GWAS datasets that explored potential gene expression links between MS and IS. After identifying significant gene sets individually of MS and IS, we performed pathway-based analysis in four biological pathway databases (KEGG, PANTHER, REACTOME, and WikiPathways) and GO categories. We discovered that there were 9 shared pathways between MS and IS in KEGG, 2 in PANTHER, 14 in REACTOME, 1 in WikiPathways, and 194 in GO annotations (p < 0.05). These results provide an improved understanding about possible shared mechanisms and treatments strategies for MS and IS. They also provide some basis for further studies of how these two diseases are linked at the molecular level.