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 present study is aimed at detecting and measuring mRNA levels of genes involved in epithelial to mesenchymal transition (EMT) in biological samples, i.e. in peripheral blood samples of colorectal cancer (CRC) patients and healthy controls, to determine the presence of disease, its progression and risk of recurrence.
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: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:Tumor metastasis remains the major cause of cancer-related death, but its molecular basis is still not well understood. Here we uncovered a splicing-mediated pathway that is essential for breast cancer metastasis. We show that the RNA-binding protein hnRNPM promotes breast cancer metastasis by activating the switch of alternative splicing that occurs during epithelial-mesenchymal transition (EMT). Genome-wide deep sequencing analysis suggests that hnRNPM potentiates TGFb signaling and identifies CD44 as a key downstream target of hnRNPM. hnRNPM ablation prevents TGFb-induced EMT and inhibits breast cancer metastasis in mice, whereas enforced expression of the specific CD44s splice isoform overrides the loss of hnRNPM and permits EMT and metastasis. Mechanistically, we demonstrate that the ubiquitously expressed hnRNPM acts in a mesenchymal-specific manner to precisely control CD44 splice isoform switching during EMT. This restricted cell-type activity of hnRNPM is achieved by competition with ESRP1, an epithelial-splicing regulator that binds to the same cis-regulatory RNA elements and is repressed during EMT. Importantly, hnRNPM is associated with aggressive breast cancer and correlates with increased CD44s in patient specimens. These findings demonstrate a novel molecular mechanism through which tumor metastasis is endowed by the hnRNPM-mediated splicing program. RNAseq for control, hnRNPM siRNA treated lung metastatic LM2 clonal line, derived from the mesenchymal MDA-MB-231 cells
Project description:Epithelial-to-mesenchymal transition (EMT) plays a crucial role in metastasis, which is the leading cause of death in breast cancer patients. We show that Cdc42 GTPase-activating protein (CdGAP) promotes tumor formation and metastasis to lungs in the HER2-positive (HER2+) murine breast cancer model. CdGAP facilitates intravasation, extravasation, and growth at metastatic sites. CdGAP depletion in HER2+ murine primary tumors mediates crosstalk with a Dlc1-RhoA pathway and is associated with a transforming growth factor-β (TGF-β)-induced EMT transcriptional signature. To further delineate the molecular mechanisms underlying the pro-migratory role of CdGAP in breast cancer cells, we searched for CdGAP interactors by performing a proteomic analysis using HEK293 cells overexpressing GFP-CdGAP. We found that CdGAP interacts with the adaptor Talin to modulate focal adhesion dynamics and integrin activation. Moreover, HER2+ breast cancer patients with high CdGAP mRNA expression combined with a high TGF-β-EMT signature are more likely to present lymph node invasion. Our results suggest CdGAP as a candidate therapeutic target for HER2+ metastatic breast cancer by inhibiting TGF-β and Integrin/Talin signaling pathways.
Project description:The biological process termed Epithelial-to-Mesenchymal Transition (EMT) plays a central role in cancer cell invasion, metastasis, self-renewal and resistance to therapy. Here, we characterize using quantitative LC-MS/MS the global changes in proteins levels occurring during EMT induced by epidermal growth factor in breast cancer MDA-MB-468 cells.
Project description:Inflammatory breast cancer (IBC) is a rare type of breast cancer but accounts for up to 10% of breast cancer-related deaths. Plasticity between epithelial and mesenchymal feature is reported to be crucial in metastasis of IBC. Using Matigel culture, we induced epithelial to mesenchymal transition (EMT) in epithelial-like SUM149 IBC cells and identified overexpressed genes in this EMT process.