Project description:Epithelial-to-mesenchymal transition (EMT) is a dynamic process that relies on cellular plasticity; an EMT/MET axis is critical for metastatic colonization of carcinomas. Unlike epithelial programming, regulation of mesenchymal programming is not well understood in EMT. Here we describe the first microRNA that enhances exclusively mesenchymal programming. We demonstrate that microRNA-424 is up-regulated early during a TWIST1/SNAI1-induced EMT, and that it causes cells to express mesenchymal genes without affecting epithelial genes, resulting in a mixed/intermediate EMT. Further, microRNA-424 increases motility, decreases adhesion and induces a growth arrest, changes associated with a complete EMT. Patient microRNA-424 levels positively associate with TWIST1/2 and EMT-like gene signatures and is increased in primary tumors versus matched normal breast. However, microRNA-424 is down-regulated in metastases versus matched primary tumors. Correspondingly, microRNA-424 decreases tumor initiation and is post-transcriptionally down-regulated in macrometastases in mice. RNA-seq identified microRNA-424 regulates numerous genes associated with EMT and breast cancer stemness including the novel miR-424 target, TGFBR3, which regulates mesenchymal phenotypes without influencing miR-424 effects on tumor-initiating phenotypes; instead, we show that ERK signaling is critical for such tumor-initiating effects of miR-424. These findings suggest microRNA-424 plays distinct roles downstream of EMT-inducing factors, facilitating earlier stages, but repressing later stages, of metastasis. Examination of mRNA levels in MCF12A human breast cell lines that stably over-expressed miR-424 or an empty vector (EV) control. Each group has three replicates.
Project description:Epithelial-to-mesenchymal transition (EMT) is a dynamic process that relies on cellular plasticity; an EMT/MET axis is critical for metastatic colonization of carcinomas. Unlike epithelial programming, regulation of mesenchymal programming is not well understood in EMT. Here we describe the first microRNA that enhances exclusively mesenchymal programming. We demonstrate that microRNA-424 is up-regulated early during a TWIST1/SNAI1-induced EMT, and that it causes cells to express mesenchymal genes without affecting epithelial genes, resulting in a mixed/intermediate EMT. Further, microRNA-424 increases motility, decreases adhesion and induces a growth arrest, changes associated with a complete EMT. Patient microRNA-424 levels positively associate with TWIST1/2 and EMT-like gene signatures and is increased in primary tumors versus matched normal breast. However, microRNA-424 is down-regulated in metastases versus matched primary tumors. Correspondingly, microRNA-424 decreases tumor initiation and is post-transcriptionally down-regulated in macrometastases in mice. RNA-seq identified microRNA-424 regulates numerous genes associated with EMT and breast cancer stemness including the novel miR-424 target, TGFBR3, which regulates mesenchymal phenotypes without influencing miR-424 effects on tumor-initiating phenotypes; instead, we show that ERK signaling is critical for such tumor-initiating effects of miR-424. These findings suggest microRNA-424 plays distinct roles downstream of EMT-inducing factors, facilitating earlier stages, but repressing later stages, of metastasis.
Project description:Immortalized non-cancerous human mammary epithelial cells (HMLE) were transfected to express the murine fusion protein Twist1-estrogen receptor(point mutation G525R) (HTER). Twist1-mediated gene expression is activated by stimulation with 4-hydroxytamoxifen for several days and induces an epithelial-mesenchymal transition (EMT) in HTER cells. In breast cancer, EMT equips cancer cells for metastasis and therapy resistance. As control, HTER cells were treated with vehicle (methanol). As additional controls, HMLE cells were stimulated with 4-hydroxytamoxifen or methanol, respectively. Prior to RNA sequencing, EMT-undergoing HTER cells were sorted by fluorescence-activated cell sorting (FACS) based on E-Cadherin and CD44 surface protein levels into three populations, epithelial (E), hybrid epithelial-mesenchymal (EM), and mesenchymal (M): E-Cadherin_high_CD44_low (E), E-Cadherin_medium_CD44_medium (EM), and E-Cadherin_low_CD44_high (M).
Project description:Epithelial to Mesenchymal Transition (EMT) has been associated with cancer cell heterogeneity, plasticity and metastasis. It has been the subject of several modeling effort. This logical model of the EMT cellular network aims to assess microenvironmental signals controlling cancer-associated phenotypes amid the EMT continuum. Its outcomes relate to the qualitative degrees of cell adhesions by adherent junctions and focal adhesions, two features affected during EMT. Model attractors recover epithelial, mesenchymal and hybrid phenotypes, and simulations show that hybrid phenotypes may arise through independent molecular paths, involving stringent extrinsic signals.
Of particular interest, model predictions and their experimental validations indicated that: 1) ECM stiffening is a prerequisite for cells overactivating FAK-SRC to upregulate SNAIL1 and acquire a mesenchymal phenotype, and 2) FAK-SRC inhibition of cell-cell contacts through the Receptor Protein Tyrosine Phosphates kappa leads to the acquisition of a full mesenchymal rather than a hybrid phenotype.
Project description:Using a TWIST1-inducible epithelial-to-mesenchymal transition (EMT) model in HMLE cells, miRNA changes were profiled at different time points during an active EMT.
Project description:This SuperSeries is composed of the following subset Series: GSE39356: MiR-374a Promotes Epithelial-Mesenchymal Transition (EMT) and Metastasis of Breast Cancer (mRNA dataset) GSE39358: MiR-374a Promotes Epithelial-Mesenchymal Transition (EMT) and Metastasis of Breast Cancer (miRNA dataset) Refer to individual Series
Project description:The core subunit of the COMPASS-like complex, WD Repeat Domain 5 (WDR5) has a prominent role in reprogramming and Epithelial-to-Mesenchymal transition (EMT) in different tumor types. Our evidences support a model in which WDR5 is prominent for EMT and metastasis dissemination in breast cancer patient-derived xenografts and cell lines. Moreover, WDR5 silencing abrogates TGFB pathway activation and reverts mesenchymal into epithelial phenotype, by inhibiting transcription of main master regulators of EMT (CDH2, TWIST1, SNAI1, SNAI2 and ZEB1). Our data suggest that WDR5 inhibition may be a successful approach to prevent progression of metastatic BC.
Project description:The core subunit of the COMPASS-like complex, WD Repeat Domain 5 (WDR5) has a prominent role in reprogramming and Epithelial-to-Mesenchymal transition (EMT) in different tumor types. Our evidences support a model in which WDR5 is prominent for EMT and metastasis dissemination in breast cancer patient-derived xenografts and cell lines. Moreover, WDR5 silencing abrogates TGFB pathway activation and reverts mesenchymal into epithelial phenotype, by inhibiting transcription of main master regulators of EMT (CDH2, TWIST1, SNAI1, SNAI2 and ZEB1). Our data suggest that WDR5 inhibition may be a successful approach to prevent progression of metastatic BC.