30 research outputs found

    Functional Characterization of FLT3 Receptor Signaling Deregulation in Acute Myeloid Leukemia by Single Cell Network Profiling (SCNP)

    Get PDF
    Molecular characterization of the FMS-like tyrosine kinase 3 receptor (FLT3) in cytogenetically normal acute myeloid leukemia (AML) has recently been incorporated into clinical guidelines based on correlations between FLT3 internal tandem duplications (FLT3-ITD) and decreased disease-free and overall survival. These mutations result in constitutive activation of FLT3, and FLT3 inhibitors are currently undergoing trials in AML patients selected on FLT3 molecular status. However, the transient and partial responses observed suggest that FLT3 mutational status alone does not provide complete information on FLT3 biological activity at the individual patient level. Examination of variation in cellular responsiveness to signaling modulation may be more informative.Using single cell network profiling (SCNP), cells were treated with extracellular modulators and their functional responses were quantified by multiparametric flow cytometry. Intracellular signaling responses were compared between healthy bone marrow myeloblasts (BMMb) and AML leukemic blasts characterized as FLT3 wild type (FLT3-WT) or FLT3-ITD. Compared to healthy BMMb, FLT3-WT leukemic blasts demonstrated a wide range of signaling responses to FLT3 ligand (FLT3L), including elevated and sustained PI3K and Ras/Raf/Erk signaling. Distinct signaling and apoptosis profiles were observed in FLT3-WT and FLT3-ITD AML samples, with more uniform signaling observed in FLT3-ITD AML samples. Specifically, increased basal p-Stat5 levels, decreased FLT3L induced activation of the PI3K and Ras/Raf/Erk pathways, decreased IL-27 induced activation of the Jak/Stat pathway, and heightened apoptotic responses to agents inducing DNA damage were observed in FLT3-ITD AML samples. Preliminary analysis correlating these findings with clinical outcomes suggests that classification of patient samples based on signaling profiles may more accurately reflect FLT3 signaling deregulation and provide additional information for disease characterization and management.These studies show the feasibility of SCNP to assess modulated intracellular signaling pathways and characterize the biology of individual AML samples in the context of genetic alterations

    Rett syndrome molecular diagnosis and implications in genetic counseling

    Get PDF
    Rett syndrome is a rare genetic X-linked dominant disorder. This syndrome is the most frequent cause of mental retardation in girls. In the classical form of the disease, the presenting signs and the course of development are characteristic. However clinical diagnosis can be very difficult when the expression is not in the classical form. Mutations in MeCP2 are responsible for 80% of cases. When MeCP2 mutation is found in an index case, genetic counseling is similar to that in other X-linked dominant genetic diseases. However, mutations in this gene can cause a spectrum of atypical forms. On the other hand, other genetic conditions like translocations, sex chromosome numerical anomalies, and mutations in other genes can complicate genetic counseling in this syndrome. We present the first case of molecular diagnosis of Rett syndrome in Iran and discuss the recent developments in its genetic counseling

    Rett syndrome molecular diagnosis and implications in genetic counseling

    Get PDF
    Rett syndrome is a rare genetic X-linked dominant disorder. This syndrome is the most frequent cause of mental retardation in girls. In the classical form of the disease, the presenting signs and the course of development are characteristic. However clinical diagnosis can be very difficult when the expression is not in the classical form. Mutations in MeCP2 are responsible for 80% of cases. When MeCP2 mutation is found in an index case, genetic counseling is similar to that in other X-linked dominant genetic diseases. However, mutations in this gene can cause a spectrum of atypical forms. On the other hand, other genetic conditions like translocations, sex chromosome numerical anomalies, and mutations in other genes can complicate genetic counseling in this syndrome. We present the first case of molecular diagnosis of Rett syndrome in Iran and discuss the recent developments in its genetic counseling

    Examination and Comparison of Various Methods of DNA Extraction from Samples of Blood, Bone Marrow Slides and Peripheral Blood

    No full text
    Introduction: DNA extraction methods are very important for genetics research and diagnostic tests. In These methods are also important for detecting genetic diseases or in cancers for investigating genetic changes during cancer progression or treatment. Therefore, selection of the best method for DNA extraction from different samples such as bone marrow (BM) or peripheral blood (PB) and their slides is very important. Methods: In the present research, DNA was extracted from 5 different samples including; 1-PB, 2-BM slides stained by Gimsa method, 3-Gimsa stained PB slides from archives, 4-new Gimsa stained PB slides and 5-non stained new PB slides by 3 different methods; salting-out, boiling and phonal chloroform method. In all of the groups, three DNA parameters were investigated; 1-OD (Optimal Density), 2-DNA concentration and 3-Outcome (PCR results). Results: The best DNA quality was achieved by salting-out method (OD=1.74), while the worst quality was by the boiling method (OD<1.0). The DNA quality of all the samples was similar in the salting-out and phenol chloroform methods. Regarding DNA quantity, the best result was from boiling method (6.7µg / ml). The least amount of DNA was obtained by the phenol chloroform method and salting-out method also resulted in the least quantity of extracted DNA. Regarding the outcome of DNA extraction or the PCR results, all the three methods showed 100% positive results for peripheral blood samples, while boiling method had the best outcome for BM slides, archive stained PB slides, new stained PB slides and non-stained PB slides (100%, 88%, 84% and 72% respectively). Discussion: The present research indicated that except non stained PB slides, the DNA extraction from all other samples showed very good results. In addition, the research showed that there is no difference in DNA extraction of new or archive slides

    Evaluation of CAG Repeat Length in the Androgen Receptor Gene and Polycystic Ovary Syndrome Risk in Iranian Women: A Case-control Study

    Full text link
    Background: Polycystic ovary syndrome (PCOS) is a heterogeneous disorder, which affects about 15-20% of women of reproductive age. The most important etiopathogenesis factor in its incidence is hyperandrogenism; over 70 candidate genes are known to be associated with this syndrome, such as the androgen receptor (AR) gene which encodes a steroid receptor and is located on the Xq11-12 chromosome. The N-terminus of exon 1 of AR contains a polymorphic trinucleotide repeat (CAG)n region that encodes glutamine tract. There are some studies showing that shorter AR CAG repeats are significantly related to enhanced AR sensitivity. Objective: This study investigated the frequency of the polymorphic expansion of the trinucleotide CAG repeats of AR in PCOS. Materials and Methods: 160 Iranian women aged 17-40 yr participated in this casecontrol study: 80 women as PCOS patients and 80 women as healthy controls according to the Rotterdam criteria. Other similar phenotype factors such as hyperandrogenism were not considered as PCOS. The frequency of polymorphic expansion of CAG trinucleotide repeats in PCOS patients was compared with the frequency in non-PCOS controls in using two primer sets for nested polymerase chain reaction. The polymerase chain reaction products were visualized on polyacrylamide gel and then were confirmed by a sequencing process. Results: The results did not show a significant correlation between the frequency of CAG repeats in AR and PCOS incidence. Conclusion: In contrast to some previous reports, the present data showed that the CAG length in PCOS cases did not significantly differ from that of controls. So, the AR (CAG)n does not appear to be a major factor for PCOS in Iranian women. Key words: Androgen receptor, (CAG)n repeats, Polycystic ovary syndrome

    Key Regulatory miRNAs and their Interplay with Mechanosensing and Mechanotransduction Signaling Pathways in Breast Cancer Progression

    No full text
    According to the WHO, breast cancer is the most common cancer in women worldwide. Identification of underlying mechanisms in breast cancer progression is the main concerns of researches. The mechanical forces within the tumor microenvironment, in addition to biochemical stimuli such as different growth factors and cytokines, activate signaling cascades, resulting in various changes in cancer cell physiology. Cancer cell proliferation, invasiveness, migration, and, even, resistance to cancer therapeutic agents are changed due to activation of mechanotransduction signaling. The mechanotransduction signaling is frequently dysregulated in breast cancer, indicating its important role in cancer cell features. So far, a variety of experimental investigations have been conducted to determine the main regulators of the mechanotransduction signaling. Currently, the role of miRNAs has been well-defined in the cancer process through advances in molecular-based approaches. miRNAs are small groups of RNAs (�22 nucleotides) that contribute to various biological events in cells. The central role of miRNAs in the regulation of various mediators involved in the mechanotransduction signaling has been well clarified over the last decade. Unbalanced expression of miRNAs is associated with different pathologic conditions. Overexpression and downregulation of certain miRNAs were found to be along with dysregulation of mechanotransduction signaling effectors. This study aimed to critically review the role of miRNAs in the regulation of mediators involved in the mechanosensing pathways and clarify how the cross-talk between miRNAs and their targets affect the cell behavior and physiology of breast cancer cells. ©2020 American Association for Cancer Research

    Aberrant methylation in promoter-associated CpG islands of multiple genes in chronic myelogenous leukemia blast crisis

    No full text
    Chronic myelogenous leukemia (CML) has a typical progressive course with transition from a chronic phase to a terminal blast crisis phase. The mechanisms that lead to disease progression remain to be elucidated. To understand the role of aberrant methylation in the progression of CML, DNA methylation patterns in 16 patients with CML blast crisis were analyzed. Methylation status was analyzed by methylation-specific PCR (MSP) for 13 genes, including cell cycle regulating genes, DNA repair genes, apoptosis-related genes, a differentiation-associated gene and a cytokine signaling gene. The frequency of samples with methylation in each of the following genes were: p15, 18%; MGMT, 12%; RARβ, 12%; p16, 6%; DAPK, 6% and FHIT, 6%. In total, four (25%) cases showed methylation of at least one gene. None of the 16 cases showed hypermethylation of the hMLH1 or hMSH2 genes. These results suggest that hypermethylation of cell cycle control genes, but not DNA mismatch repair genes, play a significant role in the progression of CML
    corecore