ABSTRACT: Expression data from ETV6-RUNX1-positive Reh leukemic cells after overexpression of miR-125b, miR-100 and miR-99a levels in different combinations
Project description:Combined overexpression of miR-125b with miR-99a and/or miR-100 induced VCR resistance in ETV6-RUNX1-positive leukemic cells Reh. We used microarrays to detail the global changes in gene expression of Reh cells upon enforced expression of miR-125 per se compared with combination of overexpression of miR-125b, miR-100 and/or miR-99a
Project description:Combined overexpression of miR-125b with miR-99a and/or miR-100 induced VCR resistance in ETV6-RUNX1-positive leukemic cells Reh. We used microarrays to detail the global changes in gene expression of Reh cells upon enforced expression of miR-125 per se compared with combination of overexpression of miR-125b, miR-100 and/or miR-99a MiR-99a and/or miR-100 were transiently overexpressed in stable miR-125b-expressing and stable scrambled miR-control-expressing Reh cells. Cellular resistance to VCR was determined by MTT assay after incubating the cells with 9 ng/mL VCR for 3 days. Changes in the gene expression pattern of Reh cells induced by miRNAs overexpression were measured using Affymetrix Arrays.
Project description:To determine the protein partners of ETV6, we expressed ETV6 and HA-tagged ETV6 in Reh pre-B leukemic cells. Anti-HA magnetic beads were used for affinity purification of ETV6-HA (and ETV6 control) from the nuclear and cytoplasmic fraction. Following purification on-beads digest and LC-MS/MS experiments were performed at the Proteomics platform of the CHU de Quebec Research Center, Quebec, Canada.
Project description:Although regulation of stem cell homeostasis by miRNAs is well studied, it is unclear how individual miRNAs, genomically encoded within an organized polycistron, can interact to induce an integrated phenotype. miR-99a/100, let-7 and miR-125b paralogues are encoded in two tricistrons on human chromosome 11 and 21. They are highly expressed in hematopoietic stem cells (HSCs) and acute megakaryoblastic leukemia (AMKL), an aggressive form of leukemia with poor prognosis. Integrative analysis of global gene expression profiling, miRNA target prediction and pathway architecture revealed that miR-99a/100, let-7 and miR-125b functionally converge at the combinatorial block of the TGFM-NM-2 pathway by targeting four receptor subunits and two SMAD signaling transducers. In addition, downregulation of tumor suppressor genes APC/APC2 stabilizes active M-NM-2-Catenin and enhances Wnt signaling. By switching the balance between Wnt and TGFM-NM-2 signaling the concerted action of these tricistronic miRNAs promoted sustained expansion of murine and human HSCs in vitro or in vivo, while favoring megakaryocytic differentiation. We lentivirally transduced cord blood CD34+-hematopoietic stem and progenitor cells (CB-HSPCs) to ectopically express miR-125b-2, miR-99a, let-7c or miR-99a~125b-2 and cultured them in megakaryocytic differentiation medium for 7 days.
Project description:Genome binding/occupancy profiling of ETS Variant Transcription Factor 6- Runt Related Transcription Factor 1 fusion protein (ETV6-RUNX1) in REH cells by high throughput sequencing. ETV6-RUNX1 is expressed in pediatric t(12;21) ETV6-RUNX1 B cell precursor acute lymphoblastic leukemia.
Project description:Although regulation of stem cell homeostasis by miRNAs is well studied, it is unclear how individual miRNAs, genomically encoded within an organized polycistron, can interact to induce an integrated phenotype. miR-99a/100, let-7 and miR-125b paralogues are encoded in two tricistrons on human chromosome 11 and 21. They are highly expressed in hematopoietic stem cells (HSCs) and acute megakaryoblastic leukemia (AMKL), an aggressive form of leukemia with poor prognosis. Integrative analysis of global gene expression profiling, miRNA target prediction and pathway architecture revealed that miR-99a/100, let-7 and miR-125b functionally converge at the combinatorial block of the TGFβ pathway by targeting four receptor subunits and two SMAD signaling transducers. In addition, downregulation of tumor suppressor genes APC/APC2 stabilizes active β-Catenin and enhances Wnt signaling. By switching the balance between Wnt and TGFβ signaling the concerted action of these tricistronic miRNAs promoted sustained expansion of murine and human HSCs in vitro or in vivo, while favoring megakaryocytic differentiation.
Project description:Arrested bone marrow (BM) lymphoid cell differentiation underlies the emergence of the most common childhood cancer, acute lymphoblastic leukemia (ALL). Recurrent genetic lesions often directly involve transcription factors (TFs), such as ETV6 and RUNX1 found in the most common ALL translocation. Here, we studied differential gene expression in ETV6-RUNX1 primary ALL samples and the REH cell line using single cell RNA-seq (scRNA-seq). Submitter declares that the raw data will be deposited in EGA due to patient privacy concerns. The raw data can be accessed at https://www.ebi.ac.uk/ega/studies/EGAS00001004374
Project description:Evidence suggests childhood acute lymphoblastic leukemia (cALL) arises in early human development. Existing models of pre-leukemic initiation using the ETV6-RUNX1 fusion do not recapitulate human disease, highlighting the need for a developmentally relevant human model system. A human pluripotent stem cell (hPSC) model genome was engineered to express ETV6-RUNX1 from the endogenous ETV6 promoter. RNA-seq data from sorted hematopoietic progenitors identified according to surface markers.
Project description:MicroRNAs (miRNAs) have been globally profiled in cancers but there tends to be poor agreement between studies including in the same cancers. Additionally, few putative miRNA targets have been validated. To overcome the lack of reproducibility, we profiled miRNAs by next generation sequencing and locked nucleic acid miRNA microarrays, and we verified concordant changes by quantitative RT-PCR. Notably, miR-125b and the miR-99 family members miR-99a, -99b, -100 were down-regulated in all assays in advanced prostate cancer cell lines relative to the parental cell lines from which they were derived. All four miRNAs were also down-regulated in human prostate tumor tissue compared to normal prostate. Transfection of miR-99a, -99b or -100 inhibited the growth of prostate cancer cells and decreased the expression of prostate-specific antigen (PSA), suggesting potential roles as tumor suppressors in this setting. To identify targets of these miRNAs, we combined computational prediction of potential targets with experimental validation by microarray and polyribosomal loading analysis. Three direct targets of the miR-99 family that were validated in this manner were the chromatin remodeling factors SMARCA5 and SMARCD1 and the growth regulatory kinase mTOR. We determined that PSA is post-transcriptionally regulated by the miR-99 family members at least partially by repression of SMARCA5. Together, our findings suggest key functions and targets of miR-99 family members in prostate cancer suppression and prognosis. C4-2 cells were transfected with miR-99a and harvested after 48hr. si-GL2 was used as control.
Project description:Breast Cancer is the cancer with most incidence and mortality in women. microRNAs are emerging as novel prognosis/diagnostic tools. Our aim was to identify a serum microRNA signature useful to predict cancer development. We focused on studying the expression levels of 30 microRNAs in the serum of 96 breast cancer patients versus 92 control individuals. Bioinformatic studies provide a microRNA signature, designated as a predictor, based upon the expression levels of 5 microRNAs. Then, we tested the predictor in a group of 60 randomly chosen women. Lastly, a proteomic study unveiled the over-expression and down-regulation of proteins differently expressed in the serum of breast cancer patients versus that of control individuals. Twenty-six microRNAs differentiate cancer tissue from healthy tissue and 16 microRNAs differentiate the serum of cancer patients from that of the control group. The tissue expression of miR-99a-5p, mir-497-5p, miR-362, and miR-1274, and the serum levels of miR-141 correlated with patient survival. Moreover, the predictor consisting of mir-125b-5p, miR-29c-3p, mir-16-5p, miR-1260, and miR-451a was able to differentiate breast cancer patients from controls. The predictor was validated in 20 new cases of breast cancer patients and tested in 60 volunteer women, assigning 11 out of 60 women to the cancer group. An association of low levels of mir-16-5p with a high content of CD44 protein in serum was found. Circulating microRNAs in serum can represent biomarkers for cancer prediction. Their clinical relevance and use of the predictor here described might be of potential importance for breast cancer prediction.