Circ_0001602 aggravates the progression of acute myeloid leukemia by regulating the miR-192-5p/ZBTB20 axis.

BACKGROUND: Acute myeloid leukemia (AML) is a malignant blood cancer with a poor prognosis and complex pathogenesis. Recently, the critical role of circular RNAs (circRNAs) has been demonstrated in the malignant progression of AML. This study aimed to investigate the functional role and underlying mechanism of circ_0001602 in AML development. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) assay was conducted for detecting the expression of circ_0001602, CCND3, microRNA-192-5p (miR-192-5p), and Zinc Finger and BTB Domain-Containing Protein 20 (ZBTB20) mRNA. RNase R assay and Actinomycin D assay were implemented to determine the characteristics of circ_0001602. Cell counting Kit-8 (CCK-8) assay was performed to evaluate cell proliferation. Flow cytometry was employed for assessing cell cycle distribution and apoptosis. Dual-luciferase reporter assay and RIP assay were utilized for confirming the interactions between miR-192-5p and circ_0001602 or ZBTB20. RESULTS: Circ_0001602 and ZBTB20 were upregulated and miR-192-5p level was reduced in AML tissues and cells. Depletion of circ_0001602 repressed cell proliferation and induced cell cycle arrest and apoptosis in AML cells. Functionally, circ_0001602 was identified to be the sponge of miR-192-5p, and miR-192-5p silence restored the suppressive effects of circ_0001602 knockdown on AML cell progression. Furthermore, ZBTB20 was a target of miR-192-5p, and ZBTB20 overexpression neutralized the miR-192-5p-mediated inhibiting actions on the malignant phenotypes of AML cells. Besides, circ_0001602 could sponge miR-192-5p to positively regulate ZBTB20 expression. CONCLUSION: Circ_0001602 contributed to AML cell development at least partially through modulating the miR-192-5p/ZBTB20 axis, which provided new insights for AML treatment.

Clinical characterization of epilepsy in children with chromosomal aberration 47, XXY.

OBJECTIVE: The phenotype of the chromosomal aberration 47, XXY exhibits considerable heterogenicity. In addition, epilepsy is extremely uncommon in individuals with this chromosomal disorder. As a result, the clinical characteristics of epilepsy in these patients remain poorly understood. METHODS: Clinical data and the evolution of epilepsy in a boy diagnosed with chromosomal aberration 47, XXY were collected and analyzed. Furthermore, a systematic literature review was conducted to examine the relationship between chromosomal aberration 47, XXY and epilepsy in children. RESULTS: We identified a novel phenotype associated with the chromosomal anomaly 47, XXY in a 2-year-2-month-old boy who presented with self-limited epilepsy with autonomic seizures at onset, followed by developmental and/or epileptic encephalopathy with spike-wave activation in sleep (D/EE-SWAS), which was responsive to corticosteroid treatment. Including the present case, we analyzed 21 cases of children diagnosed with epilepsy due to the presence of the 47, XXY chromosomal anomaly. The most common types of epilepsy were focal combined generalized epilepsy (n = 9), epileptic spasms (n = 6), and generalized epilepsy (n = 4). There were six cases of infantile epileptic spasm syndrome (IESS) (n = 5) and developmental and epileptic encephalopathy (n = 1), one case of Lennox-Gastaut syndrome, and one case of D/EE-SWAS. Apart from corticosteroids in IESS, 15 antiseizure medications (ASMs) were prescribed to eight children in this cohort, with valproate (n = 5) being the most frequently used. CONCLUSIONS: The epilepsy types and syndromes associated with the chromosomal anomaly 47, XXY demonstrated considerable heterogeneity. Among the observed phenotypes, IESS and focal epilepsy, which displayed partial responsiveness to multiple ASMs, were the most prevalent.

Adjusting the Stacking Model of Two-Dimensional Covalent Organic Frameworks for Volatile Acid Sensing via Spatial Effects.

Covalent organic frameworks (COFs) are polymer networks with a precise structure and permanent porosity, making them an attractive platform for the detection of volatile analytes due to their chemical stability and accessible active sites. In this study, based on electron-rich N,N,N',N'-tetrakis(4-aminophenyl)-1,4-benzenediamine moiety, two 2D COFs with different topological structures and stacking models were designed by the strategy of spatial effect. The conductivity of the AB-stacked COF-NUST-20 was an order of magnitude higher than that of the AA-stacked COF-NUST-30. With the protonation of the imine bond, both COFs exhibited a strong, rapid, and reversible visible color change in response to corrosive HCl vapor. In addition, the AB-stacked COF-NUST-20, which facilitates both interlayer and intralayer charge transfer, shows better sensing performance. These findings demonstrate the usefulness of all-aromatic 2D COFs as real-time responsive chemosensors and provide insight into the design of sensing materials with high sensitivity.

Intranasal influenza-vectored COVID-19 vaccine restrains the SARS-CoV-2 inflammatory response in hamsters.

The emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants and "anatomical escape" characteristics threaten the effectiveness of current coronavirus disease 2019 (COVID-19) vaccines. There is an urgent need to understand the immunological mechanism of broad-spectrum respiratory tract protection to guide broader vaccines development. Here we investigate immune responses induced by an NS1-deleted influenza virus vectored intranasal COVID-19 vaccine (dNS1-RBD) which provides broad-spectrum protection against SARS-CoV-2 variants in hamsters. Intranasal delivery of dNS1-RBD induces innate immunity, trained immunity and tissue-resident memory T cells covering the upper and lower respiratory tract. It restrains the inflammatory response by suppressing early phase viral load post SARS-CoV-2 challenge and attenuating pro-inflammatory cytokine (Il6, Il1b, and Ifng) levels, thereby reducing excess immune-induced tissue injury compared with the control group. By inducing local cellular immunity and trained immunity, intranasal delivery of NS1-deleted influenza virus vectored vaccine represents a broad-spectrum COVID-19 vaccine strategy to reduce disease burden.

Vaccination against COVID-19 and potential protective effects on seizure recurrence in children with epilepsy: A cross-sectional survey.

OBJECTIVE: Despite strong evidence on the safety and tolerability of the COVID-19 vaccine, data on vaccination in children with epilepsy, particular younger children with specific epilepsy syndromes, are limited. The protective effects of vaccination against seizure increase upon COVID-19 infection also remain to be elucidated. METHODS: Questionnaire surveys were distributed online via an established WeChat group for patient management as well as in our outpatient clinic. The data collected included demographics and clinical information related to COVID-19 vaccination and infection. Detailed information related to epilepsy diagnosis and treatment was also collected from our patient database. Logistic regression analysis was performed to determine the factors associated with non-vaccination. The characteristics of seizures following COVID-19 infection were described. RESULTS: In total, 354 suitable questionnaires were included in the study. The median age at survey was 6 years (interquartile range 4, 9). The most common epilepsy syndrome was self-limited epilepsy (n = 153, 43.2%), followed by developmental and/or epileptic encephalopathy (D/EE, n = 81, 22.9%) and genetic generalized epilepsy (n = 59, 16.7%). The vaccine uptake rate was 43.8% (n = 155), and all related side-effects (n = 11, 7.1%) remitted spontaneously. Younger age (odds ratio [OR] = 0.877, P = 0.001), D/EE (OR = 5.096, P = 0.008), and less than six months seizure-freedom before vaccination (OR = 3.026, P = 0.005) were associated with unwillingness to be vaccinated. There were no significant differences in the rate of COVID-19 infection (33.7% vs 32.7%, P = 0.879) and resultant increased seizure activity following infection between the vaccinated and unvaccinated groups after propensity score matching (9.1% vs 15.6%, P = 0.428).Three unvaccinated cases of Dravet syndrome developed status epilepticus following COVID-19 infection. SIGNIFICANCE: Vaccination against COVID-19 is safe and well tolerated in children, even in younger patients with D/EE. Although the risk of worsening seizures following COVID-19 infection may not be reduced by immunization, education focused on increased vaccination in pediatric epilepsy is still warranted.

[Gene Polymorphisms of Patients with Lymphoma-Associated Hemophagocytic Syndrome in Longyan area, Fujian Province].

OBJECTIVE: To analyze the gene polymorphisms of patients with lymphoma-associated hemophagocytic syndrome in Longyan area, Fujian province. METHODS: A total of 125 patients with lymphoma-associated hemophagocytic syndrome in Longyan, Fujian province, admitted to Longyan First Hospital from May 2017 to November 2020 were selected. Peripheral venous blood was collected from all the patients, and the genotypes of perforin 1 (PRF1) and interleukin-10 (IL-10) gene loci were detected by PCR-fluorescence probe method, and the correlation between PRF1 and IL-10 gene polymorphisms and lymphoma-associated hemophagocytic syndrome was analyzed. RESULTS: The mutation frequencies of PRF1 gene loci rs885821 (C>T), rs885822 (C>T), rs1889490 (G>A) in patients with lymphoma-associated hemophagocytic syndrome were 10.40%, 78.8% and 64.4%, respectively. The mutation frequencies of rs1800872 (A>C), rs1800871 (C>T) and rs1800896 (G>A) of IL-10 loci were 56.0%, 45.2% and 77.6%, respectively. CONCLUSION: PRF1 and IL-10 gene loci were polymorphic in patients with lymphoma-associated hemophagocytic syndrome in Longyan area, Fujian province. Alleles C and G of PRF1 and IL-10 were risk factors, and alleles T and A were protective factors.

Metformin attenuates multiple myeloma cell proliferation and encourages apoptosis by suppressing METTL3-mediated m6A methylation of THRAP3, RBM25, and USP4.

Based on the results of epidemiological and preclinical studies, metformin can improve the prognosis of patients with malignant tumors. Studies have confirmed that metformin inhibits multiple myeloma (MM) cell proliferation and promotes apoptosis. Nevertheless, the specific mechanism remains to be elucidated. MM cells were intervened with different doses of metformin to detect cell proliferation and apoptosis. Western blotting and RT-qPCR were employed to assess the expression of METTL3, METTL14, WTAP, FTO, and ALKBH5 after metformin intervention. The microarray dataset GSE29023 was retrieved from the Gene Expression Omnibus (GEO) database and calculated using the R language (limma package) to authenticate differentially expressed genes (DEGs). The database for annotation, visualization, and integrated discovery (David) was applied for GO annotation analysis of DEGs. Subsequently, the string database and Cytoscape software were applied to construct protein-protein interaction (PPI) and DEM hub gene networks. Bioinformatics analysis and MeRIP were applied to predict and test METTL3-mediated m6A levels on mRNA of THRAP3, RBM25, and USP4 in METTL3 knocked-down cells. Then rescue experiments were performed to explore effects of METTL3 and THRAP3, RBM25, or USP4 on cell proliferation and apoptosis. The effect on MM cell xenograft tumor growth was observed by injection of metformin or/and overexpression of METTL3 in in vivo experiments. Metformin decreased cell proliferation and encouraged cell apoptosis in a dose-dependent manner. Global m6A modification was elevated in MM cells compared to normal cells, which was counteracted by metformin treatment. Furthermore, THRAP3, RBM25, and USP4 were identified as possible candidate genes for metformin treatment by GSE29023 data mining. METTL3 interference impaired m6A modification on mRNA of THRAP3, RBM25, and USP4 as well as expression levels. The mRNA stability and expression of THRAP3, RBM25, and USP4 was decreased after metformin treatment, which was reversed by METTL3 overexpression. THRAP3, RBM25 or USP4 knockdown reversed the assistance of METTL3 overexpression on the malignant behavior of MM cells. Finally, upregulation of METTL3 was shown to exert facilitative effects on xenograft tumor growth by blocking metformin injection. The present study demonstrates that metformin can repress the expression of THRAP3, RBM25, and USP4 by inhibiting METTL3-mediated m6A modification, which in turn hamper cell proliferation and promotes cell apoptosis.Abbreviations: multiple myeloma (MM), Gene Expression Omnibus (GEO), differentially expressed genes (DEGs), database for annotation, visualization and integrated discovery (David), protein-protein interaction (PPI), epithelial­mesenchymal transition (EMT), methyltransferase like 3 (METTL3), methyltransferase like 14 (METTL14), wilms tumor 1-associated protein (WTAP), methyltransferase like 16 (METTL16), acute myeloid leukemia (AML), non-small lung cancer (NSCLC), glioma stem cells (GSCs), normal bone marrow-derived plasma cells (nPCs), false discovery rate (FDR), biological process (BP), optical density (OD), horseradish peroxidase (HRP), M6A RNA immunoprecipitation assay (MeRIP).

Development of alkaline phosphatase-scFv and its use for one-step enzyme-linked immunosorbent assay for His-tagged protein detection.

A histidine (His)-tag is composed of six His residues and typically exerts little influence on the structure and solubility of expressed recombinant fusion proteins. Purification methods for recombinant proteins containing His-tags are relatively well-established, thus His-tags are widely used in protein recombination technology. We established a one-step enzyme-linked immunosorbent assay (ELISA) for His-tagged recombinant proteins. We analyzed variable heavy and light chains of the anti-His-tag monoclonal antibody 4C9 and used BLAST analyses to determine variable zones in light (VL) and heavy chains (VH). VH, VL, and alkaline phosphatase (ALP) regions were connected via a linker sequence and ligated into the pGEX-4T-1 expression vector. Different recombinant proteins with His tags were used to evaluate and detect ALP-scFv activity. Antigen and anti-His-scFv-ALP concentrations for direct ELISA were optimized using the checkerboard method. ZIKV-NS1, CHIKV-E2, SCRV-N, and other His-tag fusion proteins demonstrated specific reactions with anti-His-scFv-ALP, which were accurate and reproducible when the antigen concentration was 50 µg mL-1 and the antibody concentration was 6.25 µg mL-1. For competitive ELISA, we observed a good linear relationship when coating concentrations of recombinant human anti-Müllerian hormone (hAMH) were between 0.78 and 12.5 µg mL-1. Our direct ELISA method is simple, rapid, and accurate. The scFv antibody can be purified using a prokaryotic expression system, which provides uniform product quality and reduces variations between batches.

A live attenuated virus-based intranasal COVID-19 vaccine provides rapid, prolonged, and broad protection against SARS-CoV-2.

Remarkable progress has been made in developing intramuscular vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); however, they are limited with respect to eliciting local immunity in the respiratory tract, which is the primary infection site for SARS-CoV-2. To overcome the limitations of intramuscular vaccines, we constructed a nasal vaccine candidate based on an influenza vector by inserting a gene encoding the receptor-binding domain (RBD) of the spike protein of SARS-CoV-2, named CA4-dNS1-nCoV-RBD (dNS1-RBD). A preclinical study showed that in hamsters challenged 1 d after single-dose vaccination or 9 months after booster vaccination, dNS1-RBD largely mitigated lung pathology, with no loss of body weight. Moreover, such cellular immunity is relatively unimpaired for the most concerning SARS-CoV-2 variants, especially for the latest Omicron variant. In addition, this vaccine also provides cross-protection against H1N1 and H5N1 influenza viruses. The protective immune mechanism of dNS1-RBD could be attributed to the innate immune response in the nasal epithelium, local RBD-specific T cell response in the lung, and RBD-specific IgA and IgG response. Thus, this study demonstrates that the intranasally delivered dNS1-RBD vaccine candidate may offer an important addition to the fight against the ongoing coronavirus disease 2019 pandemic and influenza infection, compensating limitations of current intramuscular vaccines.

Function of Host Protein Staufen1 in Rabies Virus Replication.

Rabies virus is a highly neurophilic negative-strand RNA virus with high lethality and remains a huge public health problem in developing countries to date. The double-stranded RNA-binding protein Staufen1 (STAU1) has multiple functions in RNA virus replication, transcription, and translation. However, its function in RABV infection and its mechanism of action are not clear. In this study, we investigated the role of host factor STAU1 in RABV infection of SH-SY-5Y cells. Immunofluorescence, TCID50 titers, confocal microscopy, quantitative real-time PCR and Western blotting were carried out to determine the molecular function and subcellular distribution of STAU1 in these cell lines. Expression of STAU1 in SH-SY-5Y cells was down-regulated by RNA interference or up-regulated by transfection of eukaryotic expression vectors. The results showed that N proficiently colocalized with STAU1 in SH-SY-5Y at 36 h post-infection, and the expression level of STAU1 was also proportional to the time of infection. Down-regulation of STAU1 expression increased the number of Negri body-like structures, enhanced viral replication, and a caused 10-fold increase in viral titers. Meanwhile, N protein and G protein mRNA levels also accumulated gradually with increasing infection time, which implied that STAU1 inhibited rabies virus infection of SH-SY-5Y cells in vitro. In conclusion, our results provide important clues for the detailed replication mechanism of rabies virus and the discovery of therapeutic targets.

miRNA-425-5p enhances diffuse large B cell lymphoma growth by targeting PTEN.

BACKGROUND: At present, cancer is one of the greatest threats to mankind, and is associated with the highest rates of morbidity and comorbidity. Recently, the advancements in molecular biology have led to an in-depth understanding of the underlying pathophysiology, which may further impact the lead time in the context of early discovery and effective therapy of cancer. Therefore, the present study proposes a better understanding of the role of micro(miR)-425-5p in diffuse large B-cell lymphoma (DLBC). METHODS: qRT-PCR was carried out to detect the relevant proteins, miRNA and mRNA RNA gene expression in DLBC cells. The effect of miR-425-5p on DLBC growth was examined by CCK-8 and colony formation assays. The binding relationship between genes was verified by dual-luciferase reporter gene assay. RESULTS: We demonstrated how the over-expression of miR-425-5p can lead to increased progression of DLBC by increasing the cellular proliferation rate and colony-forming ability. Additionally, we also found that the expression of miR-425-5p could be significantly inhibited on the basis of phosphatase and tensin homolog (PTEN) signaling pathways. CONCLUSIONS: The present study concludes that miR-425-5p is responsible for the oncogenic progression and relapse of DLBC tumorigenesis via PTEN/PI3K signaling, which can thus be effectively used to achieve better therapeutic outcomes.

LOC441178 Overexpression Inhibits the Proliferation and Migration of Esophageal Carcinoma Cells via Methylation of miR-182.

BACKGROUND: Long noncoding RNAs (lncRNAs) have been shown to play an important role in the development and progression of esophageal carcinoma (EC). Recently, lncRNA LOC441178 was shown to be dysregulated in many cancer types; however, the role of LOC441178 in EC remains unclear. MATERIALS AND METHODS: Flow cytometry, transwell and wound healing assays were used to measure the apoptosis and migration in esophageal squamous cell carcinoma (ESCC) cells. RT-qPCR was used to detect the level of miR-182 in LOC441178-overexpressed EC cells. In addition, DNA methylation status of miR-182 promoter in LOC441178-overexpressed ESCC cells was detected by methylation-specific PCR (MSP) and bisulfite sequencing PCR. RESULTS: In this study, we found that LOC441178 negatively regulated miR-182 expression in ESCC cells. In addition, overexpression of LOC441178 inhibited the proliferation and migration and induced apoptosis in ESCC cells via downregulation of miR-182. Moreover, overexpression of LOC441178 markedly inhibited the phosphorylation of Akt and phosphorylation FOXO3a and increased the expression of FOXO3a in ESCC cells via downregulation of miR-182. Mechanistically, LOC441178 overexpression epigenetically suppressed miR-182 expression via DNA methylation. In vivo experiments revealed that overexpression of LOC441178 inhibited ESCC tumor growth in mouse xenograft model. CONCLUSION: Collectively, our data suggested that LOC441178 overexpression epigenetically inhibited tumorigenesis of ESCC via DNA methylation of miR-182. These data indicated that the LOC441178/miR-182 axis might represent a novel therapeutic option for the treatment of ESCC.

[Preparation and application of anti-Mullerian hormone immunomagnetic beads].

Objective To prepare human anti-Mullerian hormone (AMH) immunomagnetic beads and HRP-labeled antibodies and establish a rapid double-antibody sandwich ELISA based on nanometer magnetic beads. Methods The expression vector of human AMH protein was constructed, and the recombinant AMH protein was expressed and purified. BALB/c mice were immunized with the recombinant protein to prepare the polyclonal antibody. Spleen cells were fused with myeloma Sp2/0 cells by PEG. Hybridoma cell lines which could stably secret monoclonal antibodies against AMH were screened out by ELISA. Monoclonal antibodies were produced from the ascites fluid of mice injected intraperitoneally with hybridoma cells and evaluated by Western blotting. Polyclonal antibodies purified from protein A were coupled to nano-magnetic' beads and used as capture antibodies, while HRP-labeled monoclonal antibody was prepared by sodium periodate method and used as probe antibody. A double antibody sandwich ELISA based on the nano-magnetic beads was established and optimized. Results A monoclonal antibody with good specificity for AMH was obtained,' and its subtype was IgG2b. The titers of purified polyclonal antibodies and monoclonal antibodies were up to 1:51 200. The capture antibody coupled with magnetic beads and the probe antibody labeled with HRP kept their good activity. The established method could detect AMH antigen within 1 hour and the detection limit was 50 ng/mL. Conclusion The prepared AMH immunomagnetic beads can be used for the fast and visualized detection of recombinant AMH.

Instrument-Free and Visual Detection of Salmonella Based on Magnetic Nanoparticles and an Antibody Probe Immunosensor.

Salmonella, a common foodborne pathogen, causes many cases of foodborne illness and poses a threat to public health worldwide. Immunological detection systems can be combined with nanoparticles to develop sensitive and portable detection technologies for timely screening of Salmonella infections. Here, we developed an antibody-probe-based immuno-N-hydroxysuccinimide (NHS) bead (AIB) system to detect Salmonella. After adding the antibody probe, Salmonella accumulated in the samples on the surfaces of the immuno-NHS beads (INBs), forming a sandwich structure (INB-Salmonella-probes). We demonstrated the utility of our AIB diagnostic system for detecting Salmonella in water, milk, and eggs, with a sensitivity of 9 CFU mL-1 in less than 50 min. The AIB diagnostic system exhibits highly specific detection and no cross-reaction with other similar microbial strains. With no specialized equipment or technical requirements, the AIB diagnostic method can be used for visual, rapid, and point-of-care detection of Salmonella.

Rapid, Visual Detection of Klebsiella pneumoniae Using Magnetic Nanoparticles and an Horseradish Peroxidase-Probe Based Immunosensor.

Klebsiella pneumoniae is a common human pathogen that causes several nosocomial chronic infections. Many methods have been reported to detect Klebsiella pneumonia; however, a simple, rapid, and visual method remains to be developed. Here, we developed a rapid, visual detection method employing a nanoparticle immunosensor (NPIS) with a sensitivity of 8 CFU mL-1. Two monoclonal antibodies (mAbs) recognizing different antigenic determinants on the surface of Klebsiella pneumonia were screened by an indirect enzyme-linked immunosorbent assay (ELISA), Western blotting, and mass spectrometry assay. The mAb 1E6 was conjugated to magnetic nanoparticles (MNPs) to generate the immuno-magnetic nanoparticles (IMNPs), whereas the horseradish peroxidase (HRP)-mAb probe was synthesized by conjugating the mAb 2F1 with HRP. Thereafter, the NPIS was developed based on the IMNPs and the HRP-mAb probe, and the total assay time for the detection of Klebsiella pneumoniae was ∼60 min. A rapid, sensitive method was developed for screening Klebsiella pneumoniae in clinical samples. The NPIS developed in this study can detect Klebsiella pneumoniae without the enrichment of bacteria and the extraction of the genome; therefore, it can be used as a primary screening method to compliment other methods in the detection of Klebsiella pneumoniae.

Development and Characterization of Double-Antibody Sandwich ELISA for Detection of Zika Virus Infection.

Zika virus (ZIKV) is an emerging mosquito-transmitted flavivirus that can cause severe disease, including congenital birth defect and Guillain-Barré syndrome during pregnancy. Although, several molecular diagnostic methods have been developed to detect the ZIKV, these methods pose challenges as they cannot detect early viral infection. Furthermore, these methods require the extraction of RNA, which is easy to contaminate. Nonstructural protein 1 (NS1) is an important biomarker for early diagnosis of the virus, and the detection methods associated with the NS1 protein have recently been reported. The aim of this study was to develop a rapid and sensitive detection method for the detection of the ZIKV based on the NS1 protein. The sensitivity of this method is 120 ng mL-1 and it detected the ZIKV in the supernatant and lysates of Vero and BHK cells, as well as the sera of tree shrews infected with the ZIKV. Without the isolation of the virus and the extraction of the RNA, our method can be used as a primary screening test as opposed to other diagnosis methods that detect the ZIKV.

Relationship between epigenetic changes in Wnt antagonists and acute leukemia.

The present study was designed to investigate the relationship among epigenetic changes in Wnt antagonists, histone H4K20me1 and the expression of tumor-suppressor genes in acute leukemia (AL) to better understand the pathogenesis of leukemia. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to detect messenger RNA (mRNA) expression levels of Wnt antagonists (Wnt5a, HDPR1, DKK1 and DKK3) in patients with AL and in normal controls; pyrophosphate sequencing was performed to detect the methylation status of the Wnt5a promoter; and western blotting was performed to detect the overall expression levels of Wnt5a protein and histone H4K20me1 in patients with acute myeloid leukemia (AML) and in normal controls. The relationship between Wnt5a protein expression and histone H4K20me1 was analyzed. Chromatin immunoprecipitation-qPCR (ChIP-qPCR) was performed to investigate the recruitment of H4K20me1 and SET8 to the Wnt5a promoter and coding regions. Our results demonstrated that the expression levels of Wnt antagonists were generally low in AML, but showed differential expression in acute lymphocytic leukemia (ALL). In most cases of AML, methylation of the Wnt5a promoter was observed and Wnt5a protein expression was low. In some cases of AML, the overall level of H4K20me1 protein was higher than that in normal controls. In addition, Wnt5a expression was positively correlated with H4K20me1 expression and was unrelated to the methylation status of its promoter. Moreover, H4K20me1 and SET8 were enriched in the Wnt5a promoter region and coding region. By contrast, Wnt5a expression was unrelated to H4K20me1 expression in normal controls. Moreover, we observed that the methylation of Wnt antagonists was often found in patients with AL, particularly those with AML, whereas the extent of methylation was variable in ALL patients. Wnt5a expression was positively correlated with the enrichment of H4K20me1 and SET8 at the Wnt5a promoter and coding regions. H4K20me1 increased Wnt5a expression by promoting transcription initiation and elongation.

[Application of Bisulfite Sequencing PCR in Detecting the Abnormal Methylation of Suppressor Gene of Wnt Signaling Pathway in Acute Promyelocytic Leukemia].

OBJECTIVE: To detect the abnormal methylation of the CPG island in the suppressor gene promoter region of the Wnt signaling pathway in cell strain NB4 of the acute promyelocytic leukemia by using the bisulfite sequcucing PCR(BSP), to screan the hyper-methylated suppressor gene of the Wnt signaling pathway and to evaluatc the potency of BSP in the methylation study. METHODS: The strain NB4 cells of the acute promyelocytic leukemia patients were used as the object, the mononuclear cells from 20 normal persons were used as the controls. The DNA was extracted and processed by bisulfite, the target sequences were amplified with PCR, then the abnormal methylation of the suppressor genes of the Wnt signaling pathway in the NB4 cells was analyzed by BSP, and the advantage and disadvantage of BSP were evaluated by comparison with the Methylation specific PCR and Pyrosequencing. RESULTS: The methylated rate of suppressor genes of the Wnt signaling pathways in the NB4 cells detected by BSP was as follows: the gene WIF1 95.26%, the gene DKK3 86%, the gene SFRP1 81.67%, the gene SFRP2 95.71%, the gene SFRP4 85%, and the gene SFRP5 95%; while the methylations in the control group were respectively as follows: the gene WIF-1 1.5%, the gene DKK3 4.2%, the gene SFRP1 0%, the gene SFRP2 0.9%, the gene SFRP4 2.5%, and the gene SFRP5 1.75%. A more significant methylation happened in the suppressor genes promoter of the Wnt signaling pathway in the NB4 cells as compared with the control group. CONCLUSION: Many hypermethylated suppressor genes are found in the Wnt signaling pathway of the acute promyelocytic leukemia NB4 cells, which may be served as one of the early diagnosis index and therapeutic target of the acute promyelocytic leukemia.

Role of HOTAIR in the diagnosis and prognosis of acute leukemia.

HOX antisense intergenic RNA (HOTAIR), a long non-coding RNA, plays an important role in the development of many types of cancers. Its function in acute leukemia (AL), however, has not been examined. The present study investigated the role of HOTAIR and its downstream genes in AL, and determined whether it could act as a molecular marker for prediction of leukemia development and prognosis. Real-time quantitative PCR was used to examine the expression of each gene in the HOTAIR signaling pathway in AL patients. The relationship between expression of HOTAIR and downstream genes and AL prognosis was analyzed. Expression of HOTAIR in patients with acute monocytic leukemia (M5) was increased as compared to controls (P<0.05). Compared to patients with low HOTAIR expression, overall survival and event-free survival of patients with high HOTAIR expression was significantly reduced. In addition, the expression of downstream genes in the HOTAIR signaling pathway including EZH2, LSD1, DNMT3A and DNMT3B was significantly increased in AL patients, and showed a significant positive correlation with high expression of HOTAIR (P<0.05). In conclusion, HOTAIR was closely related with a poor prognosis in AL patients. It may be involved in the development of leukemia by mediating methylation of DNA and histones.