The LIN28B-IMP1 post-transcriptional regulon has opposing effects on oncogenic signaling in the intestine
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA475675 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Aim: RNA binding proteins (RBPs) are expressed broadly during both development and malignant transformation, yet their mechanistic roles in epithelial homeostasis or as drivers of tumor initiation and progression are incompletely understood. Method: Here we describe a novel interplay between RBPsLIN28B and IMP1 in intestinal epithelial cells. Ribosome-profiling and RNA-sequencing identifies IMP1 as a principle nodefor gene expression regulation downstream of LIN28B. Results: In vitro and in vivo data demonstrate that epithelial IMP1 loss increases expression of WNT target genes and enhances LIN28B-mediated intestinal tumorigenesis, which was reversed when we overexpressed IMP1 independently in vivo. Furthermore, IMP1 loss in wild type or LIN28B-overexpressing mice enhancesthe regenerative response to irradiation. Conclusions: Together, our data provide new evidence for the opposing effects of the LIN28B-IMP1 axis on post-transcriptional regulation of canonical WNT signaling, with implications in intestinal homeostasis, regeneration and tumorigenesis.
2018-12-27 | GSE115647 | GEO
Project description: Not available
| S-EPMC6075153 | biostudies-literature
Project description:The RNA binding protein Lin28b is highly expressed during embryogenesis but its expression declines in adult tissues, and aberrant expression of Lin28b is associated with tumour development and maintenance. Lin28b regulates the translation of several glycolytic and mitochondrial enzymes in order to enhance cellular metabolism and energy production. Lin28b is repressed by let-7 family microRNAs in a reciprocal negative regulatory circuitry where Lin28b supresses maturation of let-7. This circuitry obtains input from master regulators such as MYC that transcriptionally upregulates Lin28b, which is required for let-7 suppression and proliferation. Not much is known of how this circuitry is regulated through transcription of the let-7 microRNAs. Here we show that the transcription factor C/EBPβ-LIP induces aerobic glycolysis and mitochondrial respiration reminiscent to cancer cell metabolism. By integrating transcriptome, proteome and metabolic flux analysis we reveal that this LIP-induced metabolic reprogramming is dependent on Lin28b and that LIP enhances Lin28b expression through transcriptional repression of the let-7 microRNA family. Transgenic mice overexpressing LIP have reduced levels of let-7 in bone marrow, skin and spleen, which is associated with induction of Lin28b and hyperplasia. This study establishes LIP as a regulator of the let-7/Lin28b regulatory circuitry and we hypothesize that the LIP-controlled let-7/Lin28b regulation is involved in the de-regulation of tissue homeostasis and tumourigenesis.
2019-11-12 | PXD010095 | Pride
Project description:Deubiquitylases (DUBs) remove ubiquitin from proteins. In the context of cancer, their inhibition can induce the degradation of oncoproteins, that may otherwise be “undruggable”. Multiple myeloma (MM) is the second most common hematological malignancy with poor outcome and high sensitivity towards ubiquitin-proteasome-system (UPS) inhibitory therapies. However, the role of DUBs in MM pathophysiology and therapy has remained elusive. Starting from genetic screening for DUB dependencies in MM, we here identify OTUD6B as a central vulnerability in MM that drives the G1/S cell cycle transition by means of deubiquitylating and stabilizing LIN28B subsequent to LIN28B phosphorylation. LIN28B regulates miRNA biogenesis and exerts high expression in embryonic stem cells that becomes re-established in certain tumors, including MM. Binding of LIN28B at G1/S activates OTUD6B, which otherwise remains in a catalytically inactive state. As a consequence, stabilized LIN28B drives MYC expression via inhibition of let7 microRNAs, which in turn allows for a rapid transition of MM cells from G1 to S phase. Analyses of primary MM patient samples reveal a positive correlation of OTUDB6B expression with poor outcome, high MYC expression and MYC target gene induction, suggesting that high MYC levels in MM result from an activation of the OTUD6B-LIN28B nexus. Together, we here specify phosphorylation and cell cycle-dependent substrate binding as a means by which OTUD6B becomes activated to drive the G1/S transition via the LIN28B-MYC axis and nominate OTUD6B and LIN28B as actionable vulnerabilities in MM.
2022-10-12 | PXD027480 | Pride
Project description:This SuperSeries is composed of the following subset Series: GSE26334: Expression data from LoVo colon cancer lines +/- constitutive LIN28B expression GSE26335: Expression data from xenograft tumors derived from LoVo colon cancer lines +/- constitutive LIN28B expression Refer to individual Series
2010-12-29 | E-GEOD-26336 | biostudies-arrayexpress
Project description:We sought to elucidate the molecular mechanisms whereby LIN28B functions by comparing the gene expression profile of cells constitutively expressing LIN28B to empty vector controls. Accordingly, we performed microarray analysis on total RNA isolated from empty vector LoVo and LIN28B-expressing LoVo colon cancer cell lines. Constitutive LIN28B expression was achieved in the LoVo (ATCC #CCL-229) colon cancer cell line via retroviral transduction of MSCV-PIG-LIN28B. Contol = empty vector MSCV-PIG.
2010-12-29 | E-GEOD-26334 | biostudies-arrayexpress
Project description:Mouse B cell precursors from fetal liver and adult bone marrow generate distinctive B cell progeny when transplanted into immunodeficient recipients, supporting a two-pathway model for B lymphopoiesis, fetal “B-1” and adult “B-2”. Recently Lin28b was shown to be important for the switch between fetal and adult pathways; however, neither the mechanism of Lin28b action nor the importance of BCR signaling in this process was addressed. Here we report important advances in our understanding of the regulation of B 1/B-2 development. First, modulation of Let-7 in fetal Pro-B cells is sufficient to alter fetal B-1 development to produce B cells resembling the progeny of adult B-2 development. Second, intact BCR signaling is required for generation of B1a B cells from Lin28b-transduced bone marrow progenitors, supporting a requirement for ligand-dependent selection, as is the case for normal B1a B cells. Third, the VH repertore of Lin28b-induced bone marrow B1a B cells differs from that of normal B1a. Finally we identify the Arid3a transcription factor as a key target of Let-7, whose ectopic expression is sufficient to induce B-1 development in adult Pro-B cells and whose knockdown blocks B-1 development in fetal Pro-B cells. 2 individual sorts of bone marrow Pro-B cells 4 days after Lin28b retroviral transduction (and 2 sorts of empty vector control) and 2 individual sorts of fetal liver Pro-B cells 4 days after Let-7b retroviral transduction (and 2 sorts of empty vector controls).
2015-03-01 | E-GEOD-65534 | biostudies-arrayexpress
Project description:We sought to elucidate functions of LIN28B and potential mechanisms whereby it may promote metastasis by comparing the gene expression profile of LIN28B metastases to primary tumors. Accordingly, we performed microarray analysis on total RNA isolated from empty vector tumors, LIN28B-LoVo tumors, and LIN28B-LoVo metastases Constitutive LIN28B expression was achieved in the LoVo (ATCC #CCL-229) colon cancer cell line via retroviral transduction of MSCV-PIG-LIN28B. xenografts were produced via injection of 1x106 cells subcutaneously into the rear flanks of nude mice. Microarrays were conducted on primary tumors from empty vector and LIN28B-expressing cells, as well as metastases derived from primary tumors constitutively expressing LIN28B. (Note: metastases did not occur with empty vector tumors)
2010-12-29 | E-GEOD-26335 | biostudies-arrayexpress
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.
2016-04-07 | E-GEOD-79980 | biostudies-arrayexpress
Project description:Chromatin remodeling proteins are frequently dysregulated in human cancer, yet little is known about how they control tumorigenesis. Here, we uncover an epigenetic program mediated by the NAD+-dependent histone deacetylase Sirtuin 6 (SIRT6) that is critical for suppression of pancreatic ductal adenocarcinoma (PDAC), one of the most lethal malignancies. SIRT6 inactivation accelerates PDAC progression and metastasis via upregulation of Lin28b, a negative regulator of the let-7 microRNA. SIRT6 loss results in histone hyperacetylation at the Lin28b promoter, Myc recruitment, and pronounced induction of Lin28b and downstream let-7 target genes, HMGA2, IGF2BP1 and IGF2BP3. This epigenetic program defines a distinct subset representing 30-40% of human PDAC, characterized by poor prognosis and an exquisite dependence on Lin28b for tumor growth. Thus, we identify SIRT6 as an important PDAC tumor suppressor, and uncover the Lin28b pathway as a potential therapeutic target in a molecularlydefined PDAC subset. Small RNA-Seq experiments for PLKO and shLIN28B (three replicates each) in human Panc3.27 PDAC cells to identify miRNAs modulateed by LIN28B knockdown.
2016-04-01 | E-GEOD-79504 | biostudies-arrayexpress