Project description:The stem cell gene LIN28B was recently shown to be overexpressed in a foetal-like subgroup of juvenile myelomonocytic leukaemia. Given the involvement of LIN28B in a variety of solid paediatric cancers, we conducted a meta-analysis of LIN28B levels using publicly available gene expression data of 1361 paediatric leukaemia samples. Interestingly, this analysis revealed LIN28B overexpression in 102 childhood leukaemia patients (7.5%), suggesting oncogenic activity for LIN28B in the context of paediatric haematological diseases. As the mode of action of LIN28B during normal and malignant haematopoiesis remains largely unexplored, we subsequently analysed the transcriptional consequences of LIN28B modulation on normal and malignant haematopoietic cells and identified the long non-coding RNA (lncRNA) H19 as the first LIN28B-regulated lncRNA. K562 cells were retrovirally transduced with shRNA GN36578 against LIN28B and a shRNA-miR non-targeting control TRH1103 (both Transomic), selected with puromycin and hybridized on Agilent microarray.
Project description:The stem cell gene LIN28B was recently shown to be overexpressed in a foetal-like subgroup of juvenile myelomonocytic leukaemia. Given the involvement of LIN28B in a variety of solid paediatric cancers, we conducted a meta-analysis of LIN28B levels using publicly available gene expression data of 1361 paediatric leukaemia samples. Interestingly, this analysis revealed LIN28B overexpression in 102 childhood leukaemia patients (7.5%), suggesting oncogenic activity for LIN28B in the context of paediatric haematological diseases. As the mode of action of LIN28B during normal and malignant haematopoiesis remains largely unexplored, we subsequently analysed the transcriptional consequences of LIN28B modulation on normal and malignant haematopoietic cells and identified the long non-coding RNA (lncRNA) H19 as the first LIN28B-regulated lncRNA. Oci-AML3 cells were retrovirally transduced with MSCV-PIG-LIN28B and MSCV-PIG-empty vectors (gifts from Johua Mendel lab), selected with puromycin and hybridized on Agilent microarray.
Project description:The stem cell gene LIN28B was recently shown to be overexpressed in a foetal-like subgroup of juvenile myelomonocytic leukaemia. Given the involvement of LIN28B in a variety of solid paediatric cancers, we conducted a meta-analysis of LIN28B levels using publicly available gene expression data of 1361 paediatric leukaemia samples. Interestingly, this analysis revealed LIN28B overexpression in 102 childhood leukaemia patients (7.5%), suggesting oncogenic activity for LIN28B in the context of paediatric haematological diseases. As the mode of action of LIN28B during normal and malignant haematopoiesis remains largely unexplored, we subsequently analysed the transcriptional consequences of LIN28B modulation on normal and malignant haematopoietic cells and identified the long non-coding RNA (lncRNA) H19 as the first LIN28B-regulated lncRNA.
Project description:The stem cell gene LIN28B was recently shown to be overexpressed in a foetal-like subgroup of juvenile myelomonocytic leukaemia. Given the involvement of LIN28B in a variety of solid paediatric cancers, we conducted a meta-analysis of LIN28B levels using publicly available gene expression data of 1361 paediatric leukaemia samples. Interestingly, this analysis revealed LIN28B overexpression in 102 childhood leukaemia patients (7.5%), suggesting oncogenic activity for LIN28B in the context of paediatric haematological diseases. As the mode of action of LIN28B during normal and malignant haematopoiesis remains largely unexplored, we subsequently analysed the transcriptional consequences of LIN28B modulation on normal and malignant haematopoietic cells and identified the long non-coding RNA (lncRNA) H19 as the first LIN28B-regulated lncRNA.
Project description:To investigate the role of lncRNA H19 in glioma, transcriptome analysis was performed on H19 overexpressed, knocked down, and control groups in U87MG and A172.
Project description:Dystrophin proteomic regulation in Muscular Dystrophies (MD) remains unclear. We report that a long noncoding RNA (lncRNA) H19 associates with dystrophin. To investigate the biological roles of this interaction in vivo, we performed mass spectrometry analysis of dystrophin and its associated proteins in H19-proficient and -deficient C2C12 myotubes. Mass spectrometry data indicated that in H19-proficient myotubes, dystrophin associates with components of dystrophin-associated protein complex (DPC); however, in H19-deficient myotubes, dystrophin associated with UBA1, UB2G1, TRIM63 ubiquitin E3 ligase and ubiquitin. In H19-deficient myotubes, dystrophin was post-translationally modified with K48-linked poly-ubiquitination at Lys3577 (referred to as Ub-DMD). This mass spectrometry study demonstrated that lncRNA H19, associates with dystrophin and inhibits E3 ligase-dependent Ub-DMD formation and its subsequent proteasomal degradation. Based on this study, H19 RNA oligonucleotides conjugated with a muscle homing ligand Agrin (referred to as AGR-H19) and Nifenazone, a TRIM63-specific small molecule inhibitor, reverses the dystrophin degradation in iPSC-derived skeletal muscle cells from Becker Muscular Dystrophy patients. Furthermore,treatment of mdx mice with exon-skipping reagent, in combination with either AGR-H19 or Nifenazone, dramatically stablized dystrophin, preserved skeletal/cardiac muscle histology, and improved strength/heart function. In summary, this mass spectrometry study paves the way to meaningful targeted therapeutics for BMD and certain DMD patients.
Project description:Using a microarray-based miRNA profiling, we found in a model of chronic myeloid leukemia (CML) that the activity of the oncoprotein BCR-ABL1 regulates the expression of miR-21, a "onco-microRNA" known to be overexpressed in numerous cancers. This relies on the phosphorylation status of STAT5, a transcription factor known to be activated by the kinase activity of BCR-ABL1. Mir-21 regulates the expression of PDCD4 (programmed cell death protein 4), a tumor suppressor identified here through a proteomics approach The microRNA repertoire of K562 cells having been either not treated (n=3) or treated (n=3) with the tyrosine kinase inhibitor Imatinib (1microM, 24h) was studied using Agilent microRNA V2 microarrays
Project description:The RNA-binding protein LIN28B is overexpressed in over 30% of patients with colorectal cancer (CRC) and is associated with poor prognosis. In the present study, we unravel a novel mechanism by which LIN28B regulates colonic epithelial cell-cell junctions and CRC metastasis. Using human CRC cells (DLD-1, Caco-2 and LoVo) with either knockdown or overexpression of LIN28B, we identified Claudin 1 (CLDN1) tight junction protein as a direct downstream target and effector of LIN28B. RNA immunoprecipitation revealed that LIN28B directly binds to and post-transcriptionally regulates CLDN1 mRNA. Furthermore, using in vitro assays and a novel murine model of metastatic CRC, we show that LIN28B-mediated CLDN1 expression enhances collective invasion, cell migration, and metastatic liver tumor formation. Bulk RNA-sequencing of the metastatic liver tumors identified NOTCH3 as a downstream effector of the LIN28B-CLDN1 axis. Additionally, genetic and pharmacologic manipulation of NOTCH3 signaling revealed that NOTCH3 was necessary for invasion and metastatic liver tumor formation. In summary, our results suggest that LIN28B promotes invasion and liver metastasis of CRC by post-transcriptionally regulating CLDN1 and activating NOTCH3 signaling. This discovery offers a promising new therapeutic option for metastatic CRC to the liver, an area where therapeutic advancements have been relatively scarce.