Abstract:Breast cancer progression toward metastatic disease is linked to re-activation of epithelial–mesenchymal transition (EMT), a latent developmental process. Breast cancer cells undergoing EMT lose epithelial characteristics and gain the capacity to invade the surrounding tissue and migrate away from the primary tumor. However, less is known about the possible role of EMT in providing cancer cells with properties that allow them to traffic to distant sites. Given the fact that pro-metastatic cancer cells share a … Show more
“…Although the expression levels of Cdh1 and another epithelial gene, Esrp2 , were not significantly decreased by 48-h treatment with TGF-β in EpRas cells, and the expression level of Cdh1 was even increased by TGF-β in EpH4 cells, we found enhanced down-regulation of Cdh1 and Esrp2 by prolonged culture of EpRas cells with TGF-β (8 days, Supplementary Fig. S1), suggesting continued alteration of transcriptional program by long-term stimulation, as previously described 26 .Figure 1Regulation of accessible chromatin regions (FAIRE-positive regions) by TGF-β at EMT-related gene loci in EpH4 and EpRas cells. ( A ) Expression levels of Cdh2 (encoding N-cadherin), Fn1 (encoding fibronectin), Cdh1 (encoding E-cadherin), and Esrp2 mRNA evaluated by RNA-seq.…”
Epithelial-mesenchymal transition (EMT) is induced by transforming growth factor (TGF)-β and facilitates tumor progression. We here performed global mapping of accessible chromatin in the mouse mammary gland epithelial EpH4 cell line and its Ras-transformed derivative (EpRas) using formaldehyde-assisted isolation of regulatory element (FAIRE)-sequencing. TGF-β and Ras altered chromatin accessibility either cooperatively or independently, and AP1, ETS, and RUNX binding motifs were enriched in the accessible chromatin regions of EpH4 and EpRas cells. Etv4, an ETS family oncogenic transcription factor, was strongly expressed and bound to more than one-third of the accessible chromatin regions in EpRas cells treated with TGF-β. While knockdown of Etv4 and another ETS family member Etv5 showed limited effects on the decrease in the E-cadherin abundance and stress fiber formation by TGF-β, gene ontology analysis showed that genes encoding extracellular proteins were most strongly down-regulated by Etv4 and Etv5 siRNAs. Accordingly, TGF-β-induced expression of Mmp13 and cell invasiveness were suppressed by Etv4 and Etv5 siRNAs, which were accompanied by the reduced chromatin accessibility at an enhancer region of Mmp13 gene. These findings suggest a mechanism of transcriptional regulation during Ras- and TGF-β-induced EMT that involves alterations of accessible chromatin, which are partly regulated by Etv4 and Etv5.
“…Although the expression levels of Cdh1 and another epithelial gene, Esrp2 , were not significantly decreased by 48-h treatment with TGF-β in EpRas cells, and the expression level of Cdh1 was even increased by TGF-β in EpH4 cells, we found enhanced down-regulation of Cdh1 and Esrp2 by prolonged culture of EpRas cells with TGF-β (8 days, Supplementary Fig. S1), suggesting continued alteration of transcriptional program by long-term stimulation, as previously described 26 .Figure 1Regulation of accessible chromatin regions (FAIRE-positive regions) by TGF-β at EMT-related gene loci in EpH4 and EpRas cells. ( A ) Expression levels of Cdh2 (encoding N-cadherin), Fn1 (encoding fibronectin), Cdh1 (encoding E-cadherin), and Esrp2 mRNA evaluated by RNA-seq.…”
Epithelial-mesenchymal transition (EMT) is induced by transforming growth factor (TGF)-β and facilitates tumor progression. We here performed global mapping of accessible chromatin in the mouse mammary gland epithelial EpH4 cell line and its Ras-transformed derivative (EpRas) using formaldehyde-assisted isolation of regulatory element (FAIRE)-sequencing. TGF-β and Ras altered chromatin accessibility either cooperatively or independently, and AP1, ETS, and RUNX binding motifs were enriched in the accessible chromatin regions of EpH4 and EpRas cells. Etv4, an ETS family oncogenic transcription factor, was strongly expressed and bound to more than one-third of the accessible chromatin regions in EpRas cells treated with TGF-β. While knockdown of Etv4 and another ETS family member Etv5 showed limited effects on the decrease in the E-cadherin abundance and stress fiber formation by TGF-β, gene ontology analysis showed that genes encoding extracellular proteins were most strongly down-regulated by Etv4 and Etv5 siRNAs. Accordingly, TGF-β-induced expression of Mmp13 and cell invasiveness were suppressed by Etv4 and Etv5 siRNAs, which were accompanied by the reduced chromatin accessibility at an enhancer region of Mmp13 gene. These findings suggest a mechanism of transcriptional regulation during Ras- and TGF-β-induced EMT that involves alterations of accessible chromatin, which are partly regulated by Etv4 and Etv5.
“…Considering the possibility that cancer cells undergoing EMT may acquire additional properties of immune cells, we performed gene profiling analysis of breast cancer cells that had been allowed to adopt an EMT program after treatment with TGF-b for 2 weeks. Intriguingly, a cluster of genes, which are normally expressed in myeloid type of immune cells including macrophages and DCs, were induced in the EMT cells (Johansson et al, 2015). These genes encode proteins with variable intracellular localization and molecular function, and while some of them previously have been linked to cancer metastasis, others have not.…”
Section: Emt Cells Hijack the Immune System To Disseminate Through Thmentioning
It was already in the 18th century when the French surgeon LeDran first noted that breast cancer patients with spread of tumor cells to their axillary lymph nodes had a drastically worse prognosis than patients without spread (LeDran et al., 1752). Since then, metastatic spread of cancer cells to regional lymph nodes has been established as the most important prognostic factor in many types of cancer (Carter et al., 1989; Elston and Ellis, 1991). However, despite its clinical importance, lymph metastasis remains an underexplored area of tumor biology. Fundamental questions, such as when, how, and perhaps most importantly, why tumor cells disseminate through the lymphatic system, remain largely unanswered. Accordingly, no treatment strategies exist that specifically target lymph metastasis. The identification of epithelial‐mesenchymal transition (EMT) as a mechanism, which allows cancer cells to dedifferentiate and acquire enhanced migratory and invasive properties, has been a game changer in cancer research. Conceptually, EMT provides an explanation for why epithelial cancers with poor differentiation status are generally more aggressive and prone to metastasize than more differentiated cancers. Inflammatory cytokines, such as TGF‐β, which are produced and secreted by tumor‐infiltrating immune cells, are potent inducers of EMT. Thus, reactivation of EMT also links cancer‐related inflammation to invasive and metastatic disease. Recently, we found that breast cancer cells undergoing TGF‐β‐induced EMT acquire properties of immune cells allowing them to disseminate in a targeted fashion through the lymphatic system similar to activated dendritic cells during inflammation. Here, we review our current understanding of the mechanisms by which cancer cells spread through the lymphatic system and the links to inflammation and the immune system. We also emphasize how imaging techniques have the potential to further expand our knowledge of the mechanisms of lymph metastasis, and how lymph nodes serve as an interface between cancer and the immune system.
“…Additionally, we observed that induction of RASSF10 by TGFβ vs. mock was highest under low cellular density (Figure 2f), which was accompanied by the phenotypical spindle like morphology and upregulation of SNAI2 [30]. We also observed that TGFβ treatment of A549 cells for two days led to an upregulation of RASSF10 and long-term TGFβ exposure (six days), when cells adopted an EMT program [31], caused an inhibition of RASSF10 expression ( Figure 2h). Consistently, short-term TGFβ treatment led to cell cycle arrest at phase G1-G0 as measured by flow cytometry (Figure 2i) in accordance with earlier results [32].…”
Section: Rassf10 Is Induced By the Emt Driver Tgfβ And Rassf10 Depletmentioning
The Ras Association Domain Family (RASSF) encodes members of tumor suppressor genes which are frequently inactivated in human cancers. Here, the function and the regulation of RASSF10, that contains a RA (Ras-association) and two coiled domains, was investigated. We utilized mass spectrometry and immuno-precipitation to identify interaction partners of RASSF10. Additionally, we analyzed the up- and downstream pathways of RASSF10 that are involved in its tumor suppressive function. We report that RASSF10 binds ASPP1 (Apoptosis-stimulating protein of p53) and ASPP2 through its coiled-coils. Induction of RASSF10 leads to increased protein levels of ASPP2 and acts negatively on cell cycle progression. Interestingly, we found that RASSF10 is a target of the EMT (epithelial mesenchymal transition) driver TGFβ (Transforming growth factor beta) and that negatively associated genes of RASSF10 are significantly over-represented in an EMT gene set collection. We observed a positive correlation of RASSF10 expression and E-cadherin that prevents EMT. Depletion of RASSF10 by CRISPR/Cas9 technology induces the ability of lung cancer cells to proliferate and to invade an extracellular matrix after TGFβ treatment. Additionally, knockdown of RASSF10 or ASPP2 induced constitutive phosphorylation of SMAD2 (Smad family member 2). Moreover, we found that epigenetic reduction of RASSF10 levels correlates with tumor progression and poor survival in human cancers. Our study indicates that RASSF10 acts a TGFβ target gene and negatively regulates cell growth and invasion through ASPP2. This data suggests that epigenetic loss of RASSF10 contributes to tumorigenesis by promoting EMT induced by TGFβ.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
