Project description:Breast cancer is the most common cancer in women with more than two million new cases diagnosed in 2018. Patients frequently develop metastases in the course of their disease which limit survival due to the lack of a curative treatment. One signaling pathway that is frequently involved in cancer initiation and progression is the WNT pathway. Breast cancer has been associated with activation of the WNT signaling pathway, although the underlying molecular mechanisms are still unclear. Here, we found the WNT receptor ROR2 to be highly expressed in aggressive breast tumors and associated with worse metastasis-free survival. In this study we addressed this question and demonstrated for the first time that WNT11 is a novel ligand for ROR2 in humans. WNT11 binds to the CRD of ROR2 and mediates WNT/PCP signaling via the RHO/ROCK pathway that confers an aggressive phenotype to breast cancer cells. ROR2 and WNT11 are both highly expressed in human brain metastases and linked with short patient survival.
Project description:Breast cancer has been associated with activation of the WNT signaling pathway, although the underlying molecular mechanisms are still unclear. In order to understand the molecular basis of these observations, we overexpressed ROR2 in human breast cancer cell lines and characterized them by RNA-Sequencing. High levels of ROR2 were associated with defects in cell morphology and cell-cell-contacts leading to increased tumor invasiveness. Using gene expression analysis we demonstrated an upregulation of several non-canonical WNT ligands in ROR2-overexpressing breast cancer cells, in particular WNT11. Knockdown of WNT11 reversed the pro-invasive phenotype and the cellular changes in ROR2-overexpressing cells. Taken together, our studies revealed a novel auto-stimulatory loop in which ROR2 triggers the expression of its own ligands, e.g. WNT11, resulting in enhanced tumor invasion associated with breast cancer metastasis.
Project description:Estrogen receptor-{alpha} (ER{alpha}) and its ligand estradiol play critical roles in breast cancer growth and are important therapeutic targets for this disease. Using chromatin immunoprecipitation (ChIP)-on-chip, ligand-bound ER{alpha} was recently found to function as a master transcriptional regulator via binding to many cis-acting sites genome-wide. Here, we used an alternative technology (ChIP cloning) and identified 94 ER{alpha} target loci in breast cancer cells. The ER{alpha}-binding sites contained both classic estrogen response elements and nonclassic binding sequences, showed specific transcriptional activity in reporter gene assay, and interacted with the key transcriptional regulators, including RNA polymerase II and nuclear receptor coactivator-3. The great majority of the binding sites were located in either introns or far distant to coding regions of genes. Forty-three percent of the genes that lie within 50 kb to an ER{alpha}-binding site were regulated by estradiol. Most of these genes are novel estradiol targets encoding receptors, signaling messengers, and ion binders/transporters. mRNA profiling in estradiol-treated breast cancer cell lines and tissues revealed that these genes are highly ER{alpha} responsive both in vitro and in vivo. Among estradiol-induced genes, Wnt11 was found to increase cell survival by significantly reducing apoptosis in breast cancer cells. Taken together, we showed novel genomic binding sites of ER{alpha} that regulate a novel set of genes in response to estradiol in breast cancer. Our findings suggest that at least a subset of these genes, including Wnt11, may play important in vivo and in vitro biological roles in breast cancer. Keywords: time course
Project description:Estrogen receptor-{alpha} (ER{alpha}) and its ligand estradiol play critical roles in breast cancer growth and are important therapeutic targets for this disease. Using chromatin immunoprecipitation (ChIP)-on-chip, ligand-bound ER{alpha} was recently found to function as a master transcriptional regulator via binding to many cis-acting sites genome-wide. Here, we used an alternative technology (ChIP cloning) and identified 94 ER{alpha} target loci in breast cancer cells. The ER{alpha}-binding sites contained both classic estrogen response elements and nonclassic binding sequences, showed specific transcriptional activity in reporter gene assay, and interacted with the key transcriptional regulators, including RNA polymerase II and nuclear receptor coactivator-3. The great majority of the binding sites were located in either introns or far distant to coding regions of genes. Forty-three percent of the genes that lie within 50 kb to an ER{alpha}-binding site were regulated by estradiol. Most of these genes are novel estradiol targets encoding receptors, signaling messengers, and ion binders/transporters. mRNA profiling in estradiol-treated breast cancer cell lines and tissues revealed that these genes are highly ER{alpha} responsive both in vitro and in vivo. Among estradiol-induced genes, Wnt11 was found to increase cell survival by significantly reducing apoptosis in breast cancer cells. Taken together, we showed novel genomic binding sites of ER{alpha} that regulate a novel set of genes in response to estradiol in breast cancer. Our findings suggest that at least a subset of these genes, including Wnt11, may play important in vivo and in vitro biological roles in breast cancer. Experiment Overall Design: This Series currently contains the gene expression data accompanying Zhihong Lin et al. Cancer Research 67,5017-5024(2007). MCF7 cells were treated with vehicle or E2 at a concentration of 10E-9 mol/L for 3 and 6 h. All experiments were performed in triplicate.
Project description:Cellular heterogeneity in breast cancer encompasses many features, yet an understanding of the coexistence and regulation of various tumor cell subpopulations remains a significant challenge in cancer biology. In the current study, we approached tumor cell heterogeneity from the perspective of Wnt pathway biology to address how different modes of Wnt signaling shape the behaviors of diverse cell populations within a heterogeneous tumor landscape. Using a syngeneic TP53 null mouse model of breast cancer, we identified distinctions in the topology of canonical Wnt b-catenin dependent signaling activity and noncanonical b-catenin independent Ror2-mediated Wnt signaling across subtypes and within tumor cell subpopulations in vivo. We further discovered an antagonistic role for Ror2 in regulating canonical Wnt/b-catenin activity in vivo, where lentiviral shRNA depletion of Ror2 expression augmented canonical Wnt/b-catenin signaling activity across multiple basal-like models. Depletion of Ror2 expression yielded distinct phenotypic outcomes and divergent alterations in gene expression programs among different tumors, despite all sharing basal-like features. Notably, we uncovered cell state plasticity and adhesion dynamics regulated by Ror2, where Ras Homology Family Member A (RhoA) and Rho-Associated Coiled-Coil Kinase 1 (ROCK1) activity downstream of Dishevelled-2 (Dvl2) were implicated. Collectively, these studies illustrate the integration and collaboration of Wnt pathways in basal-like breast cancer, where Ror2 provides a spatiotemporal function to regulate the balance of Wnt signaling and cellular heterogeneity during tumor progression.
Project description:Heterogeneity of ROR2 was observed in the tumor tissues form patient-derived xenograft (PDX) model of SCLC, in which the cells with high ROR2 expression (ROR2high cell) and those without ROR2 expression (ROR2low cell) were gained and subjected to RNA sequence analysis. Cell proliferation activity was suppressed in ROR2 KO SBC3 cells in vitro and in vivo. Comparison of the downregulated DEG in the ROR2 KO SBC3 cells and the upregulated DEG in ROR2high cells in the PDX model revealed 135 common genes. After Metascape analysis of these genes, we focus on Aurora kinases. These results suggest that ROR2 could regulate cell cycle through AURKA and/or AURKB. This study clarrifies the function of ROR2 in SCLC with heterogeneous expression condition.
Project description:Microarray analyses revealed distinct gene expression alterations in the luminal and basal epithelial compartments in the absence of Ror2 with marked alterations observed in genes associated with actin filament-based processes and the actin cytoskeletal network. Given that Ror2 expression resides in both basal and luminal epithelial cells, we wanted to identify compartment-specific functions for Ror2 in coordinating development. Accordingly, luminal and basal epithelial cell populations from shLUC and shRor2 outgrowths were isolated by FACS separation on the basis of CD24 and CD29 surface marker expression and gene expression analysis was subsequently performed using Agilent microarrays.