ABSTRACT
Objective: To summarize and analyze the clinical characteristics and gene mutations of 6 patients with Wiedemann-Steiner syndrome (WDSTS). Methods: To review and analyze the clinical data, including general conditions, clinical manifestations, growth hormone, cranial or pituitary gland magnetic resonance imaging (MRI),gene results and other data, 6 cases with WDSTS admitted to the Department of Endocrinology, Genetics and Metabolism of Jiangxi Provincial Children's Hospital and the Department of Child Care of Pingxiang Maternity and Child Care from April 2017 to February 2021 were recruited. Results: Of the 6 patients, 2 were male and 4 were female. The age of the first visit ranged from 1.0 to 11.2 years. All the 6 children presented with growth retardation and mental retardation and they all had typical facial dysmorphism and hypertrichosis (mainly on the back and limbs). Among them, case 5 had a growth hormone deficiency, and case 2 and 4 had abnormalities revealed by cranial MRI. Variations in KMT2A gene were identified in these 6 patients: c.10900+2T>C,c.10837C>T(p.Gln3613*), c.4332G>A(p.E1444E), c.2508dupC(p.W838Lfs*9), c.11695_11696delinsT(p.T3899Sfs*73), c.9915dupA (p.P3306Tfs*22).Among these variations, c.4332G>A, c.11695_11696delinsT and c.9915dupA were novel mutations. Therefore, the final diagnosis of these patients was WDSTS. Conclusions: Patients presented with short stature and mental retardation, typical facial dysmorphism and hypertrichosis should be considered WDSTS. Whole-exome sequencing plays an important role in disease diagnosis and genetic counseling.
Subject(s)
Child , Child, Preschool , Female , Humans , Infant , Male , Pregnancy , Abnormalities, Multiple , Craniofacial Abnormalities , Growth Disorders/genetics , Histone-Lysine N-Methyltransferase , Hypertrichosis/genetics , Intellectual Disability/genetics , Myeloid-Lymphoid Leukemia Protein , SyndromeABSTRACT
OBJECTIVE@#To investigate the cytotoxic effect and its mechanism of the micromolecule compound on the leukemia cells.@*METHODS@#The cytotoxic effects of 28 Nilotinib derivatives on K562, KA, KG, HA and 32D cell lines were detected by MTT assays, and the compound Nilo 22 was screen out. Cell apoptosis and cell cycle on leukemia cells were detected by flow cytometry. The effect of compound screened out on leukemogenesis potential of MLL-AF9 leukemia mice GFP@*RESULTS@#Nilo 22 serves as the most outstanding candidate out of 28 Nilotinib derivatives, which impairs leukemia cell lines, but spares normal hematopoietic cell line. Comparing with Nilotinib, Nilo 22 could induce the apoptosis of GFP@*CONCLUSION@#Nilo 22 shows a significant cytotoxic effect on mice and human leukemia cells, especially for drug resistance cells. Nilo 22 is a promising anti-leukemia agent to solve the common clinical problems of drug resistance and relapse of leukemia.
Subject(s)
Animals , Humans , Mice , Apoptosis/drug effects , Cell Cycle/drug effects , Cell Line, Tumor , Leukemia , Myeloid-Lymphoid Leukemia Protein/genetics , Telomerase/metabolism , Telomere/metabolismABSTRACT
OBJECTIVE@#To explore the genetic basis for a child with unexplained global developmental delay (GDD), seizure, and facial deformity.@*METHODS@#Whole exome sequencing (WES) was carried out for the patient. Candidate variants were verified by Sanger sequencing of the patient and his parents.@*RESULTS@#WES revealed that the patient has carried a previously unreported de novo heterozygous nonsense c.4906C>T (p.Arg1636Ter) variant of the KMT2A gene, Based on the American College of Medical Genetics and Genomics standards and guidelines, the c.4906C>T variant of KMT2A gene was predicted to be pathogenic (PVS1+ PS2+ PM2+PP3).@*CONCLUSION@#The heterozygous nonsense c.4906C>T (p.Arg1636Ter) variant of the KMT2A gene probably underlay the disease in the child. Above finding has enriched the spectrum of pathogenic variants of the KMT2A gene.
Subject(s)
Child , Humans , Male , Abnormalities, Multiple/genetics , Histone-Lysine N-Methyltransferase/genetics , Intellectual Disability/genetics , Myeloid-Lymphoid Leukemia Protein/genetics , SyndromeABSTRACT
OBJECTIVE@#To investigate the clinical features and prognosis of acute myeloid leukemia (AML) patients with the mixed lineage leukemia (MLL) gene rearrangements AF6 (MLL-AF6) positive.@*METHODS@#In the study, 11 patients who were newly diagnosed with MLL-AF6 positive AML were analyzed retrospectively, related literature was reviewed to clarify the clinical features and prognosis of MLL-AF6 positive patients.@*RESULTS@#Among the 11 patients, there were 6 males and 5 females, with a median age of 36 years. Six patients were diagnosed with AML M5 and five with M4 according to FAB classification (French-American-British classification systems). Gingival swelling and pain occurred in 6 cases and fever occurred in 5 cases. At first diagnosis, the median white blood cells were 55.5×109/L. Immunotype showed the expression of myeloid/monocyte and early stem cell series antigens. The expression level of MLL-AF6 fusion gene (real-time quantitative PCR) was 14.2%-214.5%, and 6/11 cases (54.5%) were associated with high EVI1 gene expression. Mutations of KRAS, TET2, ASXL1, TP53, DNMT3A, and FLT3-ITD were detected by next generation sequencing (NGS) in 4 patients. Chromosome G banding examination showed that 2 cases were t(6;11)(q27, q23) with complex karyotype abnormality, 4 cases with +8 abnormality and 2 cases with normal karyotype. Hematological complete remission (CR) was achieved in 8/11 patients (72.7%) after conventional induction chemotherapy, and primary drug resistance was observed in 3 patients. Two of the eight patients with CR were negative for minimal residual disease (MRD), with a median CR duration of 4.5 months. Two patients with positive MRD and three patients with refractory recurrence underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT), but all died due to leukemia progression. At the end of follow-up on December 1, 2019, 2 patients were alive and 9 died, with median survival time of 9 months.@*CONCLUSION@#The AML patients with MLL-AF6 positive were mostly young, the majority of FAB types were M4 and M5, and most of the patients often had fever as the first symptom, with increased white blood cells, accompanied by organ infiltration, and high EVI1 gene expression. The hematological remission rate of routine chemotherapy is not low, but it is difficult to achieve molecular remission, most of which have early recurrence. Early allo-HSCT in a molecular negative state may prolong the CR duration.
Subject(s)
Adult , Female , Humans , Male , Hematopoietic Stem Cell Transplantation , Leukemia, Myeloid, Acute/genetics , Myeloid-Lymphoid Leukemia Protein/genetics , Oncogene Proteins, Fusion/genetics , Prognosis , Remission Induction , Retrospective StudiesABSTRACT
OBJECTIVE@#To explore the clinical-biological characteristics and prognosis of pediatric pro-B cell acute lymphoblastic leukemia (pro-B-ALL).@*METHODS@#A total of 64 patients aged less than 18 years old with pro-BALL were enrolled. Clinical characteristics, therapeutic effect and prognostic factors were retrospectively analyzed.@*RESULTS@#Pro-B-ALL occurred in 6.23% (64/1 028) of pediatric ALL. Among the 64 patients, 35 were male and 29 were female. The median age was 7.0 years (range 0.4-16.0 years) at diagnosis, of which 39% and 6% were ≥ 10 years old and < 1 year old respectively. The median WBC count was 25.5×10@*CONCLUSIONS@#Pediatric pro-B ALL is a heterogeneous disease with clinical and biological diversity. Biological characteristics, such as immunological markers, genetic alterations, and MRD at 3 months after chemotherapy may be important factors for the long-term prognosis.
Subject(s)
Adolescent , Child , Child, Preschool , Female , Humans , Infant , Male , Antigens, CD/genetics , Disease-Free Survival , Histone-Lysine N-Methyltransferase/genetics , Myeloid-Lymphoid Leukemia Protein/genetics , Neoplasm, Residual/diagnosis , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/genetics , Prognosis , Retrospective StudiesABSTRACT
OBJECTIVE@#To investigate the clinical characteristics and prognostic influencing factors of adult AML patients with MLL rearrangement.@*METHODS@#Clinical data of 184 adult AML patients with MLL rearrangement treated in our hospital from January 2011 to December 2017 were analyzed retrospectively. The clinical features, immunophenotypic characteristics, cytogenetic characteristics, molecular biological characteristics and gene mutation characteristics were recorded, the survival and prognostic influencing factors of patients were analyzed.@*RESULTS@#Among 184 patients, 94 cases were male, 90 cases were female, median age were 36.0 years, median WBC count were 22.0×10/L, 156 cases as 84.78% for FAB typing M5, and 18 cases as 28.13% for MLL/AF9 gene positive. The median total survival time and recurrence-free survival time of 184 patients were 15.7 months and 13.3 months respectively. The cumulative total survival rate and recurrence-free survival rate by followed-up for 2 years were 36.72% and 29.33% respectively. The cumulative overall survival rate and recurrence-free survival rate of transplant recipients were significantly higher than those of non-transplant recipients by follow-up for 2 years (P＜0.05). Univariate analysis showed that age, baseline WBC count, baseline Hb levels, complete remission after one course of treatment and transplantation or no were the influencing factors of overall survival time in adult AML patients with MLL rearrangement (P＜0.05). Cox regression model multivariate analysis showed that baseline WBC count, complete remission after one course of treatment, and transplantation or no were the independent influencing factors for overall survival time in adult AML patients with MLL rearrangement（P＜0.05）.@*CONCLUSION@#Adult AML patients with MLL rearrangement are mostly belong to acute monocytic leukemia, and MLL/AF9 is the most common associated gene. Patients with AML and MLL rearrangement are prone to recurrence after routine chemotherapy. Allo-HSCT treatment is helpful to improve clinical prognosis of patients.
Subject(s)
Adult , Female , Humans , Male , Gene Rearrangement , Hematopoietic Stem Cell Transplantation , Leukemia, Myeloid, Acute , Myeloid-Lymphoid Leukemia Protein , Prognosis , Remission Induction , Retrospective StudiesABSTRACT
Abstract Case Description: We report the case of a one-year-old girl who was diagnosed with Wiedemann-Steiner Syndrome based on the identification of a novel de novo frameshift mutation in the KMT2A gene by whole exome sequencing and supported by her clinical features. Clinical Findings: KMT2A mutations cause Wiedemann-Steiner Syndrome, a very rare genetic disorder characterized by congenital hypertrichosis, short stature, intellectual disability, and distinct facial features. Treatment and Outcome: Whole exome sequencing identified a novel frameshift variant: c. 4177dupA (p.Ile1393Asnfs * 14) in KMT2A; this change generates an alteration of the specific binding to non-methylated CpG motifs of the DNA to the protein. The genotype and phenotype of the patient were compared with those of earlier reported patients in the literature. Clinical Relevance: In diseases with low frequency, it is necessary to establish a genotype-phenotype correlation that allows the establishment of therapeutic and follow-up goals. The phenotype comparation with other reported cases did not show differences attributable to sex or age among patients with Wiedemann-Steiner Syndrome. Whole exome sequencing allows identifying causality in conditions with high clinical and genetic heterogeneity like hypertrichosis.
Resumen Descripción del caso: Se reporta el caso de una paciente femenina de un año de edad, diagnosticada con Síndrome de Wiedemann-Steiner basado en la identificación de una nueva variante patogénica de novo de tipo frameshift en el gen KMT2A Mediante secuenciación de exoma usando el enfoque de trio, sumado a sus características clínicas. Hallazgos clínicos: las mutaciones en KMT2A causan el Síndrome de Wiedemann-Steiner, un desorden genético muy raro caracterizado por hipertricosis congénita, talla baja, retardo mental variable y fenotipo facial distintivo, los cuales se encuentran en la paciente reportada. Resultado: La Secuenciación de exoma completo encontró una variante de tipo frameshift: c.4177dupA (p. Ile1393Asnfs * 14) en KMT2A, este cambio a nivel génico genera una alteración de la unión específica a motivos CpG no metilados del DNA a la proteína. El genotipo y el fenotipo de la paciente fue comparado con los pacientes reportados previamente en la literatura. Relevancia clínica: En enfermedades con baja frecuencia como la aquí reportada es necesario establecer correlaciones genotipo-fenotipo que permitan establecer planes terapéuticos y de seguimiento. El análisis realizado no evidenció diferencias atribuibles a sexo o edad entre los pacientes diagnosticados con Síndrome de Weidemann-Steiner. La secuenciación de exoma permitió identificar causalidad en este caso, cuya característica principal de hipertricosis se asocia con alta heterogeneidad clínica y genética.
Subject(s)
Female , Humans , Infant , Abnormalities, Multiple/diagnosis , Histone-Lysine N-Methyltransferase/genetics , Myeloid-Lymphoid Leukemia Protein/genetics , Hypertrichosis/congenital , Intellectual Disability/genetics , Phenotype , Syndrome , Abnormalities, Multiple/genetics , Genotype , Hypertrichosis/genetics , MutationABSTRACT
OBJECTIVE@#To investigate the role of bone marrow vascular niche in the development of MLL-AF9 acute myeloid leukemia (AML).@*METHODS@#Transplantation experiments were performed to establish non-radiated MLL-AF9 AML model; the half-bone immunofluorescence staining and tile-scan imaging of two-photon confocal microscopy were used to obtain the data of 3 main bone marrow niche cells; flow cytometry analysis was performed to characterize leukemia cells in different anatomical sites.@*RESULTS@#In the early stage of MLL-AF9 AML, the proportion of leukemia cells in the metaphysis of the femur was significantly higher than that in the diaphysis. The detection of apoptosis and proliferation rate of leukemia cells showed that the percentage of leukemia cells in metaphysis significantly decreased, and the proliferation (S/G/M phase) was also significantly more active. These different features of leukemia cells may relate with different bone marrow microenvironment. The image data of 3 major components of bone marrow niche (endothelial cells, endosteum, megakaryocytes) showed different distribution of blood vessels in metaphysis and diaphysis. Furtherly comparing the spatial distance between leukemia cells and endothelial cells, endosteum, megakaryocytes indicated that leukemia cells are closer to the blood vessels, suggesting the important role of blood vessels in the development of leukemia. Glucose uptake assays and intracellular ROS detection showed that the supportive role of blood vessels for leukemia cells did not related with nutrient metabolism pathway.@*CONCLUSION@#The vascular niche plays an important role in the development of leukemia, and does not relate with the transport of nutrients and the elimination of metabolic waste, instead, which may relate with perivascular cytokines or other vascular functions.
Subject(s)
Humans , Acute Disease , Apoptosis , Bone Marrow , Bone Marrow Cells , Leukemia, Myeloid, Acute , Myeloid-Lymphoid Leukemia Protein , Oncogene Proteins, FusionABSTRACT
Mixed lineage leukemia proteins (MLL) are the key histone lysine methyltransferases that regulate expression of diverse genes. Aberrant activation of MLL promotes leukemia as well as solid tumors in humans, highlighting the urgent need for the development of an MLL inhibitor. We screened and isolated MLL1-binding ssRNAs using SELEX (Systemic Evolution of Ligands by Exponential enrichment) technology. When sequences in sub-libraries were obtained using next-generation sequencing (NGS), the most enriched aptamers—APT1 and APT2—represented about 30% and 26% of sub-library populations, respectively. Motif analysis of the top 50 sequences provided a highly conserved sequence: 5′-A[A/C][C/G][G/U][U/A]ACAGAGGG[U/A]GG[A/C] GAGUGGGU-3′. APT1, APT2, and APT5 embracing this motif generated secondary structures with similar topological characteristics. We found that APT1 and APT2 have a good binding activity and the analysis using mutated aptamer variants showed that the site information in the central region was critical for binding. In vitro enzyme activity assay showed that APT1 and APT2 had MLL1 inhibitory activity. Three-dimensional structure prediction of APT1-MLL1 complex indicates multiple weak interactions formed between MLL1 SET domain and APT1. Our study confirmed that NGS-assisted SELEX is an efficient tool for aptamer screening and that aptamers could be useful in diagnosis and treatment of MLL1-mediated diseases.
Subject(s)
Humans , Aptamers, Nucleotide , Conserved Sequence , Diagnosis , Histones , In Vitro Techniques , Leukemia , Ligands , Lysine , Mass Screening , Methyltransferases , Myeloid-Lymphoid Leukemia Protein , RNAABSTRACT
OBJECTIVE@#To assess the value of detecting the rearrangement of mixed lineage leukemia (MLL) gene in children with acute mononuclear leukemia (AML).@*METHODS@#Dual-color fluorescence in situ hybridization (FISH) probe was used to detect MLL gene rearrangement in 68 children with AML by interphase FISH. The results were compared with that of conventional G banding chromosomal analysis.@*RESULTS@#Among the 68 children, 28 were detected by FISH with positive hybridization signals, with a detection rate for MLL gene rearrangement being 41.2%. Twelve (17.6%) reciprocal translocations and interruption of 11q23 were detected by G banding analysis. The difference in the detection rates between the two methods was statistically significant (P< 0.05).@*CONCLUSION@#The sensitivity of FISH assay for MLL gene rearrangement was significantly higher than that of G banding chromosomal karyotyping. Combined use of both methods for children with AML can improve the detection rate of MLL gene rearrangements and provide crucial clues for clinical diagnosis, treatment and prognosis.
Subject(s)
Child , Humans , Chromosomes, Human, Pair 11 , Gene Rearrangement , Histone-Lysine N-Methyltransferase , Genetics , In Situ Hybridization, Fluorescence , Leukemia, Monocytic, Acute , Genetics , Myeloid-Lymphoid Leukemia Protein , Genetics , Translocation, GeneticABSTRACT
OBJECTIVE@#To assess the value of detecting multiple rearrangements of MLL gene in children with acute mononuclear leukemia (AML).@*METHODS@#Eighty six children with AML were analyzed by fluorescence in situ hybridization (FISH), chromosomal karyotyping and multiplex reverse transcription-PCR (RT-PCR).@*RESULTS@#Cross signals were detected by FISH in 26 cases, and 30.2% were detected with MLL gene rearrangements. R-band karyotyping analysis revealed 14 translocations with breakages involving 11q23 and 5 other aberrations, which yielded an overall detection rate of 22.1%. Multiple RT-PCR has detected 12 fusion genes produced by the MLL translocation, which yielded a detection rate of 14.0%. A significant difference was found in the detection rate of the three methods (P< 0.05).@*CONCLUSION@#Combined use of FISH, chromosomal karyotyping and multiplex RT-PCR can improve the detection of MLL gene rearrangements and provide important clues for clinical diagnosis, treatment and prognosis of AML.
Subject(s)
Child , Humans , Chromosomes, Human, Pair 11 , Gene Rearrangement , Histone-Lysine N-Methyltransferase , Genetics , In Situ Hybridization, Fluorescence , Karyotyping , Leukemia, Myeloid, Acute , Genetics , Myeloid-Lymphoid Leukemia Protein , Genetics , Translocation, GeneticABSTRACT
Chromosomal translocations of the human mixed-lineage leukemia (MLL) gene have been analyzed for more than 20 yr at the molecular level. So far, we have collected about 80 direct MLL fusions (MLL-X alleles) and about 120 reciprocal MLL fusions (X-MLL alleles). The reason for the higher amount of reciprocal MLL fusions is that the excess is caused by 3-way translocations with known direct fusion partners. This review is aiming to propose a solution for an obvious problem, namely why so many and completely different MLL fusion alleles are always leading to the same leukemia phenotypes (ALL, AML, or MLL). This review is aiming to explain the molecular consequences of MLL translocations, and secondly, the contribution of the different fusion partners. A new hypothesis will be posed that can be used for future research, aiming to find new avenues for the treatment of this particular leukemia entity.
Subject(s)
Humans , Alleles , Chromosomes, Human, X , Epigenesis, Genetic , Leukemia/classification , Myeloid-Lymphoid Leukemia Protein/chemistry , Protein Structure, Tertiary , Translocation, GeneticABSTRACT
No abstract available.
Subject(s)
Adolescent , Humans , Male , Chromosomes, Human, Pair 11 , Chromosomes, Human, Pair 4 , Gene Rearrangement , Histone-Lysine N-Methyltransferase/genetics , Myeloid-Lymphoid Leukemia Protein/genetics , Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/geneticsABSTRACT
No abstract available.
Subject(s)
Adult , Female , Humans , Male , Middle Aged , CD4 Antigens/metabolism , CD56 Antigen/metabolism , Bone Marrow/metabolism , Dendritic Cells/cytology , Diagnostic Errors , Exons , Flow Cytometry , Gene Rearrangement , Hematologic Neoplasms/diagnosis , Histone-Lysine N-Methyltransferase/genetics , Immunohistochemistry , In Situ Hybridization, Fluorescence , Leukemia, Myeloid, Acute/diagnosis , Myeloid-Lymphoid Leukemia Protein/genetics , Real-Time Polymerase Chain Reaction , Sequence Analysis, DNA , Transcription Factors/genetics , Translocation, GeneticABSTRACT
No abstract available.
Subject(s)
Female , Humans , Male , Young Adult , Base Sequence , Cell Cycle Proteins/genetics , Chromosomes, Human, Pair 11 , Chromosomes, Human, Pair 22 , Gene Rearrangement , Histone-Lysine N-Methyltransferase/genetics , Immunophenotyping , In Situ Hybridization, Fluorescence , Karyotype , Leukemia, Myeloid, Acute/diagnosis , Myeloid-Lymphoid Leukemia Protein/genetics , Oncogene Proteins, Fusion/genetics , Reverse Transcriptase Polymerase Chain Reaction , Septins/genetics , Sequence Analysis, DNA , Translocation, GeneticABSTRACT
Objective: Peritraumatic reactions feature prominently among the main predictors for development of posttraumatic stress disorder (PTSD). Peritraumatic tonic immobility (PTI), a less investigated but equally important type of peritraumatic response, has been recently attracting the attention of researchers and clinicians for its close association with traumatic reactions and PTSD. Our objective was to investigate the role of PTI, peritraumatic panic, and dissociation as predictors of PTSD symptoms in a cohort of police recruits (n=132). Methods: Participants were asked to complete the following questionnaires during academy training and after the first year of work: Posttraumatic Stress Disorder Checklist - Civilian Version (PCL-C), Physical Reactions Subscale (PRS), Peritraumatic Dissociative Experiences Questionnaire (PDEQ), Tonic Immobility Scale (TIS), and Critical Incident History Questionnaire. Results: Employing a zero-inflated negative binomial regression model, we found that each additional point in the TIS was associated with a 9% increment in PCL-C mean scores (RM = 1.09), whereas for PRS, the increment was 7% (RM = 1.07). As the severity of peritraumatic dissociation increased one point in the PDEQ, the chance of having at least one symptom in the PCL-C increased 22% (OR = 1.22). Conclusions: Our findings highlight the need to expand investigation on the incidence and impact of PTI on the mental health of police officers. .
Subject(s)
Animals , Humans , Mice , Chromosomal Proteins, Non-Histone/physiology , Leukemia/pathology , Myeloid-Lymphoid Leukemia Protein/genetics , Neoplastic Stem Cells/pathology , Oncogenes , Repressor Proteins/physiology , Apoptosis , Chromosomal Proteins, Non-Histone/genetics , Flow Cytometry , Leukemia/genetics , Leukemia/metabolism , Polymerase Chain Reaction , Repressor Proteins/geneticsABSTRACT
<p><b>OBJECTIVE</b>To evaluate the efficiency of one-step multiplex RT-PCR for identifying four common fusion transcripts (TEL/AML1, E2A/PBX1, MLL/AF4 and BCR/ABL) in children with acute lymphoblastic leukemia (ALL).</p><p><b>METHODS</b>Total RNA was extracted from bone marrow samples of 76 children who were newly diagnosed with ALL between January 2003 and December 2010. These RNAs were analyzed for TEL/AML1, E2A/PBX1, MLL/AF4 and BCR/ABL by one-step multiplex RT-PCR or common nested-multiplex PCR. The PCR products were confirmed by DNA sequencing.</p><p><b>RESULTS</b>TEL/AML1 was found in 12 cases (the length of products was 298 bp in 9 cases and 259 bp in 3 cases), E2A/PBX1 was found in 3 cases (the length of products was 373 bp), BCR/ABL was found in 1 case (the length of products was 2 124 bp), and MLL/AF4 was found in 7 cases (the length of products was 427 bp in 1 case and 673 bp in 6 cases) using one-step multiplex RT-PCR combined with DNA sequencing. The results were consistent with those using common nested-multiplex PCR.</p><p><b>CONCLUSIONS</b>One-step multiplex RT-PCR may be another alternative for detection of common fusion transcripts in children with ALL.</p>
Subject(s)
Child , Child, Preschool , Female , Humans , Infant , Male , Core Binding Factor Alpha 2 Subunit , Genetics , Fusion Proteins, bcr-abl , Genetics , Multiplex Polymerase Chain Reaction , Methods , Myeloid-Lymphoid Leukemia Protein , Genetics , Oncogene Proteins, Fusion , Genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Genetics , Reverse Transcriptase Polymerase Chain Reaction , Methods , Sequence Analysis, DNAABSTRACT
<p><b>OBJECTIVE</b>To analyze the clinical features and prognosis of acute leukemia patients with the mixed lineage leukemia（MLL）gene rearrangements AF10 positive.</p><p><b>METHODS</b>6 cases with MLL-AF10 positive were analyzed retrospectively, related literatures were reviewed to clarify MLL-AF10 patients'clinical features and prognosis.</p><p><b>RESULTS</b>The median age of 6 cases was 19.5 years old, 5 patients with fever onset, the onset white blood cells of 4 patients were less than 10×10⁹/L. 5 cases were as M₅ and 1 case M₄ according to FAB classification, the level of fusion gene（RQ-PCR）was 0.23%-22.60% when diagnosed, 4 cases had concomitant WT1 gene mutation, flow cytometry disclosed myeloid phenotype. Of 5 evaluated patients achieved the first complete remission after conventional chemotherapy, 2 cases of complex karyotype died, one case died of sepsis in induction, another died from failing of transplantation. 4 out of 5 transplant recipients gained long term survival.</p><p><b>CONCLUSION</b>The MLL-AF10 positive patients were mostly young men, the majority FAB classification was M5 or M4, often onset with fever, low white blood cells and low level of fusion gene, usually associated with WT1 mutation. Conventional chemotherapy produced a high response rate, but easy to relapse, while the complex karyotype had a poor prognosis, allo-HSCT may have the potential to improve the prognosis of MLL-AF10 positive patients.</p>
Subject(s)
Female , Humans , Male , Young Adult , Acute Disease , Chromosomes, Human, Pair 11 , Flow Cytometry , Gene Rearrangement , Leukemia , Diagnosis , Genetics , Myeloid-Lymphoid Leukemia Protein , Genetics , Phenotype , Polymerase Chain Reaction , Prognosis , Proto-Oncogenes , Recurrence , Remission Induction , Retrospective StudiesABSTRACT
<p><b>OBJECTIVE</b>To establish the ADAR1 (adenosine deaminase that act on RNA 1) knockout MLL-AF9 acute myeloid leukemia (AML) mouse model, and to preliminarily investigate the effects of ADAR1 deletion on the development of AML.</p><p><b>METHODS</b>The lineage⁻ (Lin⁻) cells of ER-CreADAR1(lox/lox) mice and their ADAR1(lox/lox) counterparts were enriched by magnetic activated cell sorting (MACS) and then transduced with retrovirus carrying MSCV- MLL/AF9-IRES-GFP fusion gene. The efficiency of transduction was detected by flow cytometry, and equal number of GFP⁺ cells were transplanted into lethally irradiated recipient mice. The recipient mice were treated with tamoxifen at 48 hours after transplantation to induce ADAR1 knockout and divided into following groups: experimental group (ER-Cre;ADAR1(lox/lox)+tamoxifen), control groups ((1)ER-Cre;ADAR1(lox/lox)+vechile, (2)ADAR1(lox/lox)+tamoxifen, (3)ADAR1(lox/lox)+vechile). The percentage of GFP⁺ cells in peripheral blood was examined at 10, 15 and 20 days respectively after transplantation and the survival of the recipient mice was observed. In vitro study, ER-Cre;ADAR1(lox/lox) and ADAR1(lox/lox) AML cells were cultured and the apoptosis rates of these cells 48 hours after 4-hydroxytamoxifen treatment were examined.</p><p><b>RESULTS</b>The ADAR1 deletion MLL-AF9 AML mouse model was successfully established. Deletion of ADAR1 could decrease the percentage of GFP⁺ cells in the peripheral blood and significantly prolong the survival rate of recipient mice（P<0.05）. In vitro study showed that the cultured total cell number, percentage of GFP⁺ cells decreased and the apoptosis rate of AML cells increased.</p><p><b>CONCLUSION</b>Ablation of ADAR1 could delay the progression of AML in recipient mice. ADAR1 plays a critical role in the development and maintenance of murine MLL-AF9 AML.</p>
Subject(s)
Animals , Mice , Adenosine Deaminase , Apoptosis , Disease Models, Animal , Leukemia, Myeloid, Acute , Myeloid-Lymphoid Leukemia Protein , TamoxifenABSTRACT
During normal postnatal mammary gland development and adult remodeling related to the menstrual cycle, pregnancy, and lactation, ovarian hormones and peptide growth factors contribute to the delineation of a definite epithelial cell identity. This identity is maintained during cell replication in a heritable but DNA-independent manner. The preservation of cell identity is fundamental, especially when cells must undergo changes in response to intrinsic and extrinsic signals. The maintenance proteins, which are required for cell identity preservation, act epigenetically by regulating gene expression through DNA methylation, histone modification, and chromatin remodeling. Among the maintenance proteins, the Trithorax (TrxG) and Polycomb (PcG) group proteins are the best characterized. In this review, we summarize the structures and activities of the TrxG and PcG complexes and describe their pivotal roles in nuclear estrogen receptor activity. In addition, we provide evidence that perturbations in these epigenetic regulators are involved in disrupting epithelial cell identity, mammary gland remodeling, and breast cancer initiation.