scholarly journals Epigenetic Reprogramming of Tissue-Specific Transcription Promotes Metastasis

2017 ◽  
Author(s):  
Shuaishuai Teng ◽  
Yang Li ◽  
Ming Yang ◽  
Rui Qi ◽  
Yiming Huang ◽  
...  

SUMMARYTumor metastasis is the cause of death for 90% of cancer patients, and no currently-available therapies target this multi-step process in which cancer cells spread from the local tissue of a primary tumor to distant organs where they establish secondary tumors1. Although epithelial-to-mesenchymal transition2, tumor-secreted exosomes3, epigenetic regulators as well as other genes4-8 have been implicated in metastasis, little is known about how cells adapt to and colonize new tissue environments. Here, we show that the epigenetics-mediated reprogramming of tissue-specific gene transcription in cancer cells promotes metastasis. Using colorectal cancer (CRC) as a model, we found in both clinical and cell line studies that metastatic CRC cells lose their colon-specific gene transcription program and gain a liver-specific gene transcription program as they metastasize in the liver. Further, we found this transcription reprogramming is driven by a reshaped epigenetic landscape of both typical and super-enhancers. Chemical inhibition of enhancer activity disrupts the ability of cells to execute altered transcription programs and consequently inhibits metastasis. Binding motif analysis of the enhancers in liver metastatic CRC cells identified the liver-specific transcription factor FOXA2 as a key regulator, and knocking down of FOXA2 expression prevents the colonization of metastatic CRC cells in the liver of a mice xenograft model. These results, together with additional observations of similar reprogramming in several cohorts of clinical CRC tumor samples and in multiple other forms of metastatic cancers, indicate that this reprogramming may be a common feature of metastasis in multiple cancers and suggest the targeted disruption of this epigenetic reprogramming as a strategy for the development of therapies to treat metastasis, the leading cause of cancer-related mortality.

2021 ◽  
Vol 12 ◽  
Author(s):  
Joel R. Wilmore ◽  
Brian T. Gaudette ◽  
Daniela Gómez Atria ◽  
Rebecca L. Rosenthal ◽  
Sarah Kim Reiser ◽  
...  

Antibody secreting plasma cells are made in response to a variety of pathogenic and commensal microbes. While all plasma cells express a core gene transcription program that allows them to secrete large quantities of immunoglobulin, unique transcriptional profiles are linked to plasma cells expressing different antibody isotypes. IgA expressing plasma cells are generally thought of as short-lived in mucosal tissues and they have been understudied in systemic sites like the bone marrow. We find that IgA+ plasma cells in both the small intestine lamina propria and the bone marrow are long-lived and transcriptionally related compared to IgG and IgM expressing bone marrow plasma cells. IgA+ plasma cells show signs of shared clonality between the gut and bone marrow, but they do not recirculate at a significant rate and are found within bone marrow plasma cells niches. These data suggest that systemic and mucosal IgA+ plasma cells are from a common source, but they do not migrate between tissues. However, comparison of the plasma cells from the small intestine lamina propria to the bone marrow demonstrate a tissue specific gene transcription program. Understanding how these tissue specific gene networks are regulated in plasma cells could lead to increased understanding of the induction of mucosal versus systemic antibody responses and improve vaccine design.


2018 ◽  
Vol 40 (6) ◽  
pp. 805-818 ◽  
Author(s):  
Sharleen V Menezes ◽  
Leyla Fouani ◽  
Michael L H Huang ◽  
Bekesho Geleta ◽  
Sanaz Maleki ◽  
...  

AbstractThe metastasis suppressor, N-myc downstream-regulated gene-1 (NDRG1), plays multifaceted roles in inhibiting oncogenic signaling and can suppress the epithelial mesenchymal transition (EMT), a key step in metastasis. In this investigation, NDRG1 inhibited the oncogenic effects of transforming growth factor-β (TGF-β) in PANC-1 pancreatic cancer cells, promoting expression and co-localization of E-cadherin and β-catenin at the cell membrane. A similar effect of NDRG1 at supporting E-cadherin and β-catenin co-localization at the cell membrane was also demonstrated for HT-29 colon and CFPAC-1 pancreatic cancer cells. The increase in E-cadherin in PANC-1 cells in response to NDRG1 was mediated by the reduction of three transcriptional repressors of E-cadherin, namely SNAIL, SLUG and ZEB1. To dissect the mechanisms how NDRG1 inhibits nuclear SNAIL, SLUG and ZEB1, we assessed involvement of the nuclear factor-κB (NF-κB) pathway, as its aberrant activation contributes to the EMT. Interestingly, NDRG1 comprehensively inhibited oncogenic NF-κB signaling at multiple sites in this pathway, suppressing NEMO, Iĸĸα and IĸBα expression, as well as reducing the activating phosphorylation of Iĸĸα/β and IĸBα. NDRG1 also reduced the levels, nuclear co-localization and DNA-binding activity of NF-κB p65. Further, Iĸĸα, which integrates NF-κB and TGF-β signaling to upregulate ZEB1, SNAIL and SLUG, was identified as an NDRG1 target. Considering this, therapies targeting NDRG1 could be a new strategy to inhibit metastasis, and as such, we examined novel anticancer agents, namely di-2-pyridylketone thiosemicarbazones, which upregulate NDRG1. These agents downregulated SNAIL, SLUG and ZEB1 in vitro and in vivo using a PANC-1 tumor xenograft model, demonstrating their marked potential.


2021 ◽  
Author(s):  
Maria Evers ◽  
Jingwen Song ◽  
Pratik Shriwas ◽  
Harrison S Greenbaum ◽  
Xiaozhuo Chen

Abstract Background: Epithelial mesenchymal transition (EMT) is an early process in metastasis. Extracellular ATP (eATP) was shown to play important roles in EMT. However, the mechanisms by which eATP induces EMT and ATP’s relationship to TGF-b, a well-known EMT inducer, are unclear. Key questions include: if and how much EMT-specific gene expression eATP induces and how similar is ATP-induced EMT to TGF-b-induced EMT? We hypothesized that eATP acts as a specific inducer and regulator of EMT at all levels alternative to TGF-b in cancer cells. Methods: As EMT involves changes from gene expression to metabolites, RNAseq and metabolomics analyses were performed on human NSCLC A549 cells treated with either eATP or TGF-b to determine how they induce EMT at transcription and metabolic levels. Bio-functional assays, such as Transwell invasion, intracellular ATP, resazurin cell viability, fluorescence microscopy of filopodia formation, and antibody neutralization / cell rescue, were conducted in more NSCLC cell lines to validate changes identified from RNAseq and metabolomics analyses by confirming the corresponding EMT phenotypic changes.Results: RNAseq analysis shows that eATP significantly enriched expressions of genes involved in EMT temporarily, and similarly but non-identically to TGF-b after 2 and 6 hours of treatment. Eleven genes, with known or unknown functions in EMT, are significantly upregulated by both inducers at both time points, have been identified. Metabolomics analysis revealed eATP induced numerous EMT-related changes in metabolic pathways, including cytoskeleton rearrangement, glycolysis, glutaminolysis, ROS, and individual metabolic changes similar or identical to those induced by TGF-b. eATP-induced transcriptomic changes appeared smaller but earlier than TGF-b. Functional bioassays verified the RNAseq and metabolomics findings that eATP induced earlier and more invasion and formation of filopodia in A549 and H1299 cells, and restored viability of cancer cells treated with TGF-b-neutralizing antibodies. Conclusions: eATP-induced EMT, from gene expression changes and metabolic reprogramming, is similar but non-identical to that induced by TGF-b, and is independent of TGF-b. The smaller but earlier EMT-related changes induced by eATP, compared with TGF-b, could be largely explained by extracellular action of eATP and intracellular activities of macropinocytosis-internalized eATP. These strongly indicate that eATP is an emerging master inducer and regulator of EMT.


2021 ◽  
Vol 12 (12) ◽  
Author(s):  
Ziqian Yan ◽  
Zhimei Sheng ◽  
Yuanhang Zheng ◽  
Ruijun Feng ◽  
Qinpei Xiao ◽  
...  

AbstractStudies have shown that cancer-associated fibroblasts (CAFs) play an irreplaceable role in the occurrence and development of tumors. Therefore, exploring the action and mechanism of CAFs on tumor cells is particularly important. In this study, we compared the effects of CAFs-derived exosomes and normal fibroblasts (NFs)-derived exosomes on breast cancer cells migration and invasion. The results showed that exosomes from both CAFs and NFs could enter into breast cancer cells and CAFs-derived exosomes had a more enhancing effect on breast cancer cells migration and invasion than NFs-derived exosomes. Furthermore, microRNA (miR)-18b was upregulated in CAFs-derived exosomes, and CAFs-derived exosomes miR-18b can promote breast cancer cell migration and metastasis by specifically binding to the 3′UTR of Transcription Elongation Factor A Like 7 (TCEAL7). The miR-18b-TCEAL7 pathway promotes nuclear Snail ectopic activation by activating nuclear factor-kappa B (NF-κB), thereby inducing epithelial-mesenchymal transition (EMT) and promoting cell invasion and metastasis. Moreover, CAFs-derived exosomes miR-18b could promote mouse xenograft model tumor metastasis. Overall, our findings suggest that CAFs-derived exosomes miR-18b promote nuclear Snail ectopic by targeting TCEAL7 to activate the NF-κB pathway, thereby inducing EMT, invasion, and metastasis of breast cancer. Targeting CAFs-derived exosome miR-18b may be a potential treatment option to overcome breast cancer progression.


2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Jinxia Li ◽  
Chunyan Dai ◽  
Li Shen

Background. Ursolic acid (UA) is an antitumor component derived from Chinese herbal medicine; this study is to observe the effects of UA on epithelial-mesenchymal transition (EMT) in gastric cancer. Methods. (1) In vitro experiments: 25μmol/L and 50μmol/L UA were applied to BGC-823, AGS, MGC-803, and HGC-27 cells; MTT staining, Transwell assay, and flow cytometry were used to assess cell proliferation, cell migration, and apoptosis, respectively. Western blot was performed to detect the expressions of N-Cadherin, Vimentin, Snail, Twist, Axl, p-Axl, IKK, p-IKK, NF-κB, and p-NF-κB. (2) In vivo experiments: Ten BALB/c-nu mice were used to establish gastric cancer xenograft model. Five were orally given UA for 4 weeks and five were given normal saline. Expressions of N-Cadherin and Snail were examined by immunohistochemical assay; expressions of N-Cadherin, Snail, Twist, Axl, p-Axl, IKK, and p-IKK were detected by Western blot. Results. (1) UA inhibited cell proliferation in BGC-823 and HGC-27 cells in dose-dependent manners. (2) UA inhibited cell migration in BGC-823, AGS, and MGC-803 cells while inducing apoptosis in BGC-823 cells. (3) UA significantly decreased the expressions of N-Cadherin, Vimentin, Snail, Twist p-Axl, p-IKKα/β, and p-NF-κB in BGC-823 and MGC-803 cells. (4) UA distinctly decreased the expressions of N-Cadherin, Snail, p-Axl, and p-IKKα/β in gastric cancer xenograft model rats. Conclusion. UA can effectively inhibit the proliferation and migration and induce apoptosis of gastric cancer cells. The antitumor effect of UA is conducted by EMT inhibition, which may be associated with the regulation of Axl/NF-κB signaling pathway.


2020 ◽  
Vol 21 (20) ◽  
pp. 7469 ◽  
Author(s):  
Jin Hong Lim ◽  
Kyung Hwa Choi ◽  
Soo Young Kim ◽  
Cheong Soo Park ◽  
Seok-Mo Kim ◽  
...  

Cancer cells can exhibit resistance to different anticancer drugs by acquiring enhanced anti-apoptotic potential, improved DNA injury resistance, diminished enzymatic inactivation, and enhanced permeability, allowing for cell survival. However, the genetic mechanisms for these effects are unknown. Therefore, in this study, we obtained drug-sensitive HT-29 cells (commercially) and drug-resistant cancer cells (derived from biochemically and histologically confirmed colon cancer patients) and performed microarray analysis to identify genetic differences. Cellular proliferation and other properties were determined after treatment with oxaliplatin, lenvatinib, or their combination. In vivo, tumor volume and other properties were examined using a mouse xenograft model. The oxaliplatin and lenvatinib cotreatment group showed more significant cell cycle arrest than the control group and groups treated with either agent alone. Oxaliplatin and lenvatinib cotreatment induced the most significant tumor shrinkage in the xenograft model. Drug-resistant and metastatic colon cancer cells evaded the anticancer drug effects via angiogenesis. These findings present a breakthrough strategy for treating drug-resistant cancer.


1997 ◽  
Vol 272 (7) ◽  
pp. 4287-4294 ◽  
Author(s):  
Shi-Fang Yan ◽  
Yu Shan Zou ◽  
Monica Mendelsohn ◽  
Yun Gao ◽  
Yoshifumi Naka ◽  
...  

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Chunhong Fu ◽  
Ming Yuan ◽  
Jie Sun ◽  
Gang Liu ◽  
Xiaojuan Zhao ◽  
...  

Ovarian cancer is one of the most lethal gynecologic malignancies for women. Due to the lack of efficient target therapy, the overall survival rate for patients with advanced ovarian cancer is still low. Illustrating the molecular mechanisms dictating ovarian cancer progression is critically important to develop novel therapeutic agents. Here, we found that RNA-binding motif protein 11 (RBM11) was highly elevated in ovarian cancer tissues compared with normal ovary, while RBM11 depletion in ovarian cancer cells resulted in impaired cell growth and invasion. Moreover, knockdown of RBM11 also retarded tumor growth in the A2780 ovarian cancer xenograft model. Mechanically, we found that RBM11 positively regulated Akt/mTOR signaling pathway activation in ovarian cancer cells. Thus, these results identify RBM11 is a novel oncogenic protein and prognostic biomarker for ovarian cancers.


1994 ◽  
Vol 14 (5) ◽  
pp. 3494-3503
Author(s):  
U Yavuzer ◽  
C R Goding

For a gene to be transcribed in a tissue-specific fashion, expression must be achieved in the appropriate cell type and also be prevented in other tissues. As an approach to understanding the regulation of tissue-specific gene expression, we have analyzed the requirements for melanocyte-specific expression of the tyrosinase-related protein 1 (TRP-1) promoter. Positive regulation of TRP-1 expression is mediated by both an octamer-binding motif and an 11-bp element, termed the M box, which is conserved between the TRP-1 and other melanocyte-specific promoters. We show here that, consistent with its ability to activate transcription in a non-tissue-specific fashion, the M box binds the basic-helix-loop-helix factor USF in vitro. With the use of a combination of site-directed mutagenesis and chimeric promoter constructs, additional elements involved in regulating TRP-1 expression were identified. These include the TATA region, which appears to contribute to the melanocyte specificity of the TRP-1 promoter. Mutational analysis also identified two repressor elements, one at the start site, the other located at -240, which function both in melanoma and nonmelanoma cells. In addition, a melanocyte-specific factor, MSF, binds to sites which overlap both repressor elements, with substitution mutations demonstrating that binding by MSF is not required for repression. Although a functional role for MSF has not been unequivocally determined, the location of its binding sites leads us to speculate that it may act as a melanocyte-specific antirepressor during transcription of the endogenous TRP-1 gene.


2006 ◽  
Vol 26 (5) ◽  
pp. 1589-1597 ◽  
Author(s):  
Denis Klochkov ◽  
Héctor Rincón-Arano ◽  
Elena S. Ioudinkova ◽  
Viviana Valadez-Graham ◽  
Alexey Gavrilov ◽  
...  

ABSTRACT The tissue-specific chicken α-globin gene domain represents one of the paradigms, in terms of its constitutively open chromatin conformation and the location of several regulatory elements within the neighboring housekeeping gene. Here, we show that an 0.2-kb DNA fragment located ∼4 kb upstream to the chicken α-globin gene cluster contains a binding site for the multifunctional protein factor CTCF and possesses silencer activity which depends on CTCF binding, as demonstrated by site-directed mutagenesis of the CTCF recognition sequence. CTCF was found to be associated with this recognition site in erythroid cells but not in lymphoid cells where the site is methylated. A functional promoter directing the transcription of the apparently housekeeping ggPRX gene was found 120 bp from the CTCF-dependent silencer. The data are discussed in terms of the hypothesis that the CTCF-dependent silencer stabilizes the level of ggPRX gene transcription in erythroid cells where the promoter of this gene may be influenced by positive cis-regulatory signals activating α-globin gene transcription.


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