Project description:JorA might inhibit the proliferation, migration and promote apoptosis of GC cells AGS by down-regulating the expression of target LGR5 and β-catenin, and then regulating the LGR5/Wnt/β-catenin signaling pathway.
Project description:To address the role of endothelial Wnt/β-catenin signaling in CNS angiogenesis, we compared the bulk transcriptomes of WT and Wnt/β-catenin signaling-deficient PHBC endothelial cells, prior to CNS vascular invasion. To this end, we used three approaches to abrogate endothelial Wnt/β-catenin signaling: Morpholino-mediated knock-down of gpr124, reck or wnt7aa. We find that the expression of mmp25b is decreased in PHBC endothelial cells of all Wnt/β-catenin signaling deficient conditions as compared to the WT controls.
Project description:The tumor suppressor gene adenomatous polyposis coli (APC) is mutated in most colorectal cancers (CRC) resulting in constitutive Wnt activation. To understand the Wnt-activating mechanism of APC mutation, we applied CRISPR/Cas9 technology to engineer various APC-truncated isogenic lines. We find that the β-catenin inhibitory domain (CID) in APC represents the threshold for pathological levels of Wnt activation and tumor transformation. Mechanistically, CID-deleted APC truncation promotes β-catenin deubiquitination through reverse binding of β-TrCP and USP7 to the destruction complex. USP7 depletion in APC-mutated CRC inhibits Wnt activation by restoring β-catenin ubiquitination, drives differentiation and suppresses xenograft tumor growth. Finally, the Wnt-activating role of USP7 is specific to APC mutations, thus can be used as tumor-specific therapeutic target for most CRCs.
Project description:The Wnt pathway is a key regulator of embryonic development, cell growth, differentiation, polarity formation, neural development, carcinogenesis, and stem cell self-renewal, and deregulation of the Wnt signalling is associated with many human disease. The central player in the Wnt pathway is β-catenin, A recent study has shown that β-catenin/Tcf/Lef signaling pathway is an essential growth-regulatory pathway in cardiomyocytes. We used DNA microarrays to detail the global trends in gene expression underlying β-catenin-overexpressed cardiomyocytes and identified distinct classes of up- or down-regulated genes during this process. Our findings suggest that β-catenin plays a critical role in regulating cardiac dysfunction at transcriptional level and may provide novel insight into how β-catenin modulates heart diseases. Cardiomyocytes were infected with GFP control or β-catenin adenoviruses for RNA extraction and hybridization on Affymetrix microarrays. We sought to define the effects of β-catenin on the global programme of gene expression in primary cardiomyocytes. To that end, neonatal rat cardiomyocytes were infected with GFP control (G) or β-catenin adenovirus (B) for 24 hours.
Project description:Canonical Wnt/β-catenin signalling is an essential regulator of various cellular functions throughout development and adulthood. Aberrant Wnt/β-catenin signalling also contributes to various pathologies including cancer, necessitating an understanding of cell context dependent mechanisms regulating this pathway. Since protein-protein interactions underpin β-catenin function and localization, we sought to identify novel β-catenin interacting partners by affinity purification coupled with tandem mass spectrometry in vascular smooth muscle cells (VSMCs), where β-catenin is involved in both physiological and pathological control of cell proliferation. Here, we report novel components of the VSMC β-catenin interactome.
Project description:The Notch signaling pathway regulates fate decision, proliferation and differentiation of intestinal epithelial cells. However, the role of Notch signaling in colorectal cancer progression is largely unknown. Here we show that Notch signaling suppresses the progression of colorectal tumorigenesis, even though it augments tumor initiation. In contrast to adenomas of Apcmin mice, Notch-inactivated Apcmin adenomas showed more malignant characteristics, such as submucosal invasion and loss of glandular pattern. Conversely, Notch-activated Apcmin adenomas showed a reversion from high-grade to low-grade features, such as the restoration of adherent junctions. Expression profiling revealed that Notch signaling promotes the differentiation of tumor cells with down regulation of Wnt/beta-catenin target genes and inhibition of epithelial-mesenchymal transition. Comparison of mouse and human expression profiles also suggests the common role of Notch in inhibition of tumor progression. Interestingly, Notch signaling suppressed the expression of beta-catenin responsive genes through chromatin modification of Tcf4/beta-catenin binding sides. Our results suggest that Notch signaling has dual roles in colorectal tumorigenesis: promoting adenoma initiation, while inhibiting tumor progression to colorectal cancer. mRNAs from normal (WT, Notch-activated and Notch-inactivated) and tumor (WT, Notch-activated and Notch-inactivated) tissues were profiled.
Project description:Because of its insensitivity to existing radiotherapy, namely chemotherapy and targeted treatments, triple-negative breast cancer (TNBC) remains a great challenge to overcome. Increasing evidence has indicated abnormal Wnt/β-catenin pathway activation in TNBC but not luminal or HER2+ breast cancer, and lncRNAs play a key role in a variety of cancers. Through lncRNA microarray profiling between activated and inactivated wnt/β-catenin pathway of TNBC tissues, lnc-WAL (wnt/β-catenin associated lncRNA; WAL) was selected as the top upregulated lncRNA in wnt/β-catenin pathway activation compared with the inactivation group. RIP-seq was used to compare the β-catenin and IgG groups, where lnc-WAL could interact with β-catenin. Clinically, increased lnc-WAL in TNBC tumor tissue was associated with shorter survival. lnc-WAL promoted EMT, the proliferation, migration and invasion of breast cancer stem cells (BCSCs), and TNBC cells. Mechanistically, lnc-WAL inhibited β-catenin protein degradation via Axin-mediated phosphorylation at serine 45. Subsequently, β-catenin accumulated in the nucleus and activated the target genes. Importantly, wnt/β-catenin pathway activation stimulated the transcription of lnc-WAL. These results pointed to a master regulatory role of lnc-WAL/Axin/β-catenin in the malignant progression of TNBC. Our findings provide important clinical translational evidence that lnc-WAL may be a potential therapeutic target against TNBC.
Project description:We hypothesized that DKK3 may exert oncogenic function supecifically in head and neck squamous cell carcinoma (HNSCC). DKK3 overexpression in HNSCC cell resulted in elevated cellular proliferation, migration, invasion and in vivo tumor growth. This elevated malignant properties was not driven by Wnt/beta-catenin pathway.
Project description:The Wnt pathway is a key regulator of embryonic development, cell growth, differentiation, polarity formation, neural development, carcinogenesis, and stem cell self-renewal, and deregulation of the Wnt signalling is associated with many human disease. The central player in the Wnt pathway is β-catenin, A recent study has shown that β-catenin/Tcf/Lef signaling pathway is an essential growth-regulatory pathway in cardiomyocytes. We used DNA microarrays to detail the global trends in gene expression underlying β-catenin-overexpressed cardiomyocytes and identified distinct classes of up- or down-regulated genes during this process. Our findings suggest that β-catenin plays a critical role in regulating cardiac dysfunction at transcriptional level and may provide novel insight into how β-catenin modulates heart diseases.
Project description:During mesenchymal stem cell (MSC) differentiation, both Wnt signaling and the development of a rigid cytoskeleton promote commitment to the osteoblastic over adipogenic lineage. β-catenin is thought to play a critical role in Wnt effects. We show that β-catenin was additive with cytoskeletal signals to prevent adipogenesis, and β-catenin knockdown promoted adipogenesis even when the actin cytoskeleton was depolymerized. β-catenin also prevented osteoblast commitment in a cytoskeletal-independent manner, with β-catenin knockdown enhancing lineage commitment. Chip-seq showed that β-catenin associated with the promoter of EZH2, a key component of the PRC2 complex that governs genome methylation. Knocking down β-catenin lowered EZH2 levels and H3K27me3 at osteogenic loci. Further, when EZH2 was inhibited, β-catenin ’s anti-differentiation effects were lost. These results indicate that regulating EZH2 activity is key to β-catenin effects on MSC to preserve MSC multipotentiality.