scholarly journals Epithelial-mesenchymal plasticity through loss of CTCF motif accessibility and protein expression

2021 ◽  
Author(s):  
Kelsey S Johnson ◽  
Shaimaa Hussein ◽  
Priyanka Chakraborty ◽  
Arvind Muruganantham ◽  
Sheridan Mikhail ◽  
...  
Keyword(s):  
Protein Expression ◽  
Epithelial Mesenchymal Transition ◽  
Function Analysis ◽  
Chromatin Accessibility ◽  
Ctcf Binding ◽  
Breast Cancer Cell Lines ◽  
Loss Of Function ◽  
Binding Motifs ◽  
Mesenchymal Transition ◽  
Partial States

Epithelial-mesenchymal transition (EMT) and its reversal, mesenchymal-epithelial transition (MET) drive tissue reorganization critical for early development. In carcinomas, processing through EMT, MET or partial states promotes migration, invasion, dormancy, and metastatic colonization. As a reversible process, EMT is inherently regulated at epigenetic and epigenomic levels. To understand the epigenomic nature of reversible EMT and its partial states, we characterized chromatin accessibility dynamics, transcriptomic output, protein expression, and cellular phenotypes during stepwise reversible EMT. We found that the chromatin insulating protein machinery, including CTCF, is suppressed and re-expressed, coincident with broad alterations in chromatin accessibility, during EMT/MET and is lower in triple-negative breast cancer cell lines with EMT features. Through analysis of chromatin accessibility using ATAC-seq, we identify that early phases of EMT are characterized by enrichment for AP-1 family member binding motifs but also by diminished enrichment for CTCF binding motifs. Through loss-of-function analysis we demonstrate that suppression of CTCF alters cellular plasticity, facilitating entrance into a partial EMT state. These findings are indicative of a role of CTCF and chromatin reorganization for epithelial-mesenchymal plasticity.

scholarly journals CTCF Expression and Dynamic Motif Accessibility Modulates Epithelial–Mesenchymal Gene Expression

Cancers ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 209
Author(s):  
Kelsey S. Johnson ◽  
Shaimaa Hussein ◽  
Priyanka Chakraborty ◽  
Arvind Muruganantham ◽  
Sheridan Mikhail ◽  
...  
Keyword(s):  
Gene Expression ◽  
Epithelial Mesenchymal Transition ◽  
Function Analysis ◽  
Chromatin Accessibility ◽  
Ctcf Binding ◽  
Breast Cancer Cell Lines ◽  
Loss Of Function ◽  
Binding Motifs ◽  
Mesenchymal Transition ◽  
Partial States

Epithelial–mesenchymal transition (EMT) and its reversal, mesenchymal–epithelial transition (MET) drive tissue reorganization critical for early development. In carcinomas, processing through EMT, MET, or partial states promotes migration, invasion, dormancy, and metastatic colonization. As a reversible process, EMT is inherently regulated at epigenetic and epigenomic levels. To understand the epigenomic nature of reversible EMT and its partial states, we characterized chromatin accessibility dynamics, transcriptomic output, protein expression, and cellular phenotypes during stepwise reversible EMT. We find that the chromatin insulating protein machinery, including CTCF, is suppressed and re-expressed, coincident with broad alterations in chromatin accessibility, during EMT/MET, and is lower in triple-negative breast cancer cell lines with EMT features. Through an analysis of chromatin accessibility using ATAC-seq, we identify that early phases of EMT are characterized by enrichment for AP-1 family member binding motifs, but also by a diminished enrichment for CTCF binding motifs. Through a loss-of-function analysis, we demonstrate that the suppression of CTCF alters cellular plasticity, strengthening the epithelial phenotype via the upregulation of epithelial markers E-cadherin/CDH1 and downregulation of N-cadherin/CDH2. Conversely, the upregulation of CTCF leads to the upregulation of EMT gene expression and an increase in mesenchymal traits. These findings are indicative of a role of CTCF in regulating epithelial–mesenchymal plasticity and gene expression.

scholarly journals Chromatin-directed proteomics-identified network of endogenous androgen receptor in prostate cancer cells

Oncogene ◽  
2021 ◽  
Author(s):  
Kaisa-Mari Launonen ◽  
Ville Paakinaho ◽  
Gianluca Sigismondo ◽  
Marjo Malinen ◽  
Reijo Sironen ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Androgen Receptor ◽  
Target Genes ◽  
Epithelial Mesenchymal Transition ◽  
Protein A ◽  
Chorioallantoic Membrane ◽  
Chromatin Accessibility ◽  
Castration Resistant Prostate Cancer ◽  
Novel Therapy ◽  
Mesenchymal Transition

AbstractTreatment of prostate cancer confronts resistance to androgen receptor (AR)-targeted therapies. AR-associated coregulators and chromatin proteins hold a great potential for novel therapy targets. Here, we employed a powerful chromatin-directed proteomics approach termed ChIP-SICAP to uncover the composition of chromatin protein network, the chromatome, around endogenous AR in castration resistant prostate cancer (CRPC) cells. In addition to several expected AR coregulators, the chromatome contained many nuclear proteins not previously associated with the AR. In the context of androgen signaling in CRPC cells, we further investigated the role of a known AR-associated protein, a chromatin remodeler SMARCA4 and that of SIM2, a transcription factor without a previous association with AR. To understand their role in chromatin accessibility and AR target gene expression, we integrated data from ChIP-seq, RNA-seq, ATAC-seq and functional experiments. Despite the wide co-occurrence of SMARCA4 and AR on chromatin, depletion of SMARCA4 influenced chromatin accessibility and expression of a restricted set of AR target genes, especially those involved in cell morphogenetic changes in epithelial-mesenchymal transition. The depletion also inhibited the CRPC cell growth, validating SMARCA4’s functional role in CRPC cells. Although silencing of SIM2 reduced chromatin accessibility similarly, it affected the expression of a much larger group of androgen-regulated genes, including those involved in cellular responses to external stimuli and steroid hormone stimulus. The silencing also reduced proliferation of CRPC cells and tumor size in chick embryo chorioallantoic membrane assay, further emphasizing the importance of SIM2 in CRPC cells and pointing to the functional relevance of this potential prostate cancer biomarker in CRPC cells. Overall, the chromatome of AR identified in this work is an important resource for the field focusing on this important drug target.

scholarly journals Long noncoding RNA LINC00941 promotes pancreatic cancer progression by competitively binding miR-335-5p to regulate ROCK1-mediated LIMK1/Cofilin-1 signaling

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jie Wang ◽  
Zhiwei He ◽  
Jian Xu ◽  
Peng Chen ◽  
Jianxin Jiang
Keyword(s):  
Pancreatic Cancer ◽  
Cell Growth ◽  
Cell Lines ◽  
Cancer Progression ◽  
Noncoding Rna ◽  
Epithelial Mesenchymal Transition ◽  
Loss Of Function ◽  
Mesenchymal Transition

AbstractAn accumulation of evidence indicates that long noncoding RNAs are involved in the tumorigenesis and progression of pancreatic cancer (PC). In this study, we investigated the functions and molecular mechanism of action of LINC00941 in PC. Quantitative PCR was used to examine the expression of LINC00941 and miR-335-5p in PC tissues and cell lines, and to investigate the correlation between LINC00941 expression and clinicopathological features. Plasmid vectors or lentiviruses were used to manipulate the expression of LINC00941, miR-335-5p, and ROCK1 in PC cell lines. Gain or loss-of-function assays and mechanistic assays were employed to verify the roles of LINC00941, miR-335-5p, and ROCK1 in PC cell growth and metastasis, both in vivo and in vitro. LINC00941 and ROCK1 were found to be highly expressed in PC, while miR-335-5p exhibited low expression. High LINC00941 expression was strongly associated with larger tumor size, lymph node metastasis, and poor prognosis. Functional experiments revealed that LINC00941 silencing significantly suppressed PC cell growth, metastasis and epithelial–mesenchymal transition. LINC00941 functioned as a molecular sponge for miR-335-5p, and a competitive endogenous RNA (ceRNA) for ROCK1, promoting ROCK1 upregulation, and LIMK1/Cofilin-1 pathway activation. Our observations lead us to conclude that LINC00941 functions as an oncogene in PC progression, behaving as a ceRNA for miR-335-5p binding. LINC00941 may therefore have potential utility as a diagnostic and treatment target in this disease.

scholarly journals A radiosensitizer, gallotannin-rich extract from Bouea macrophylla seeds, inhibits radiation-induced epithelial-mesenchymal transition in breast cancer cells

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jiraporn Kantapan ◽  
Siwaphon Paksee ◽  
Aphidet Duangya ◽  
Padchanee Sangthong ◽  
Sittiruk Roytrakul ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Dna Damage ◽  
Cell Death ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Epithelial Mesenchymal Transition ◽  
Breast Cancer Cell Lines ◽  
Mesenchymal Transition ◽  
Mammosphere Formation ◽  
Radiation Induced

Abstract Background Radioresistance can pose a significant obstacle to the effective treatment of breast cancers. Epithelial–mesenchymal transition (EMT) is a critical step in the acquisition of stem cell traits and radioresistance. Here, we investigated whether Maprang seed extract (MPSE), a gallotannin-rich extract of seed from Bouea macrophylla Griffith, could inhibit the radiation-induced EMT process and enhance the radiosensitivity of breast cancer cells. Methods Breast cancer cells were pre-treated with MPSE before irradiation (IR), the radiosensitizing activity of MPSE was assessed using the colony formation assay. Radiation-induced EMT and stemness phenotype were identified using breast cancer stem cells (CSCs) marker (CD24−/low/CD44+) and mammosphere formation assay. Cell motility was determined via the wound healing assay and transwell migration. Radiation-induced cell death was assessed via the apoptosis assay and SA-β-galactosidase staining for cellular senescence. CSCs- and EMT-related genes were confirmed by real-time PCR (qPCR) and Western blotting. Results Pre-treated with MPSE before irradiation could reduce the clonogenic activity and enhance radiosensitivity of breast cancer cell lines with sensitization enhancement ratios (SERs) of 2.33 and 1.35 for MCF7 and MDA-MB231cells, respectively. Pretreatment of breast cancer cells followed by IR resulted in an increased level of DNA damage maker (γ-H2A histone family member) and enhanced radiation-induced cell death. Irradiation induced EMT process, which displayed a significant EMT phenotype with a down-regulated epithelial marker E-cadherin and up-regulated mesenchymal marker vimentin in comparison with untreated breast cancer cells. Notably, we observed that pretreatment with MPSE attenuated the radiation-induced EMT process and decrease some stemness-like properties characterized by mammosphere formation and the CSC marker. Furthermore, pretreatment with MPSE attenuated the radiation-induced activation of the pro-survival pathway by decrease the expression of phosphorylation of ERK and AKT and sensitized breast cancer cells to radiation. Conclusion MPSE enhanced the radiosensitivity of breast cancer cells by enhancing IR-induced DNA damage and cell death, and attenuating the IR-induced EMT process and stemness phenotype via targeting survival pathways PI3K/AKT and MAPK in irradiated breast cancer cells. Our findings describe a novel strategy for increasing the efficacy of radiotherapy for breast cancer patients using a safer and low-cost natural product, MPSE.

Nano-Coated si-SNHG14 Regulated PD-L1 Expression and Decreased Epithelial-Mesenchymal Transition in Nasopharyngeal Carcinoma Cells

2021 ◽  
Vol 17 (10) ◽  
pp. 1993-2002
Author(s):  
Haoran Yu ◽  
Chen Zhang ◽  
Wanpeng Li ◽  
Xicai Sun ◽  
Quan Liu ◽  
...  
Keyword(s):  
Nasopharyngeal Carcinoma ◽  
Epithelial Mesenchymal Transition ◽  
Animal Experiments ◽  
Loss Of Function ◽  
Mesenchymal Transition ◽  
Non Coding Rna ◽  
Long Non Coding Rna ◽  
Tumor Agent

To investigate the expression characteristics of long non-coding RNA SNHG14 in nasopharyngeal carcinoma (NPC) and its effects on epithelial-mesenchymal transition and development of nano-coated si-SNHG14 as an anti-tumor agent. The SNHG14 expression in cancerous and adjacent non-cancerous tissues was monitored using reverse transcriptionpolymerase chain reaction (RT-PCR). Gain- and loss-of-function experiments tested the regulation of SNHG14, miR- 5590-3p, and ZEB1 on PD-L1. The binding association between the above three factors was verified using bioinformatics analysis. EMT-related E-cadherin, N-cadherin, and Vimentin were tested using Western blot. Animal experiments in nude mice verified the function of SNHG14 in the EMT of NPC in vivo. The nano-coated si-SNHG14 was developed as an anti-tumor agent and was verified NPC cell in vitro. SNHG14 was upregulated in NPC tissues. Knocking down SNHG14 markedly inhibited the EMT of NPC. Additionally, the expression of ZEB1 was positively related to that of the SNHG14, while it was inversely correlated with that of miR-5590-3p. Moreover, ZEB1 transcription upregulated PD-L1 and promoted the EMT, while SNHG14 could accelerate the EMT of NPC in vivo by regulating the PD-1 and PD-L1. SNHG14-miR-5590- 3p-ZEB1 positively regulated PD-L1 and facilitate the EMT of NPC. Nano-coated si-SNHG14 significantly downregulated PD-L1 expression and decreased EMT.

scholarly journals The role of protein kinase PAK1 in the regulation of estrogen-independent growth of breast cancer

2014 ◽  
Vol 60 (3) ◽  
pp. 322-331 ◽  
Author(s):  
E.A. Avilova ◽  
O.E. Andreeva ◽  
V.A. Shatskaya ◽  
M.A. Krasilnikov
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Intracellular Signaling ◽  
Breast Cancer Cells ◽  
Epithelial Mesenchymal Transition ◽  
Breast Cancer Cell Lines ◽  
Hormone Resistance ◽  
Mesenchymal Transition

The main goal of this work was to study the intracellular signaling pathways responsible for the development of hormone resistance and maintaining the autonomous growth of breast cancer cells. In particular, the role of PAK1 (p21-activated kinase 1), the key mitogenic signaling protein, in the development of cell resistance to estrogens was analyzed. In vitro studies were performed on cultured breast cancer cell lines: estrogen-dependent estrogen receptor (ER)-positive MCF-7 cells and estrogen-resistant ER-negative HBL-100 cells. We found that the resistant HBL-100 cells were characterized by a higher level of PAK1 and demonstrated PAK1 involvement in the maintaining of estrogen-independent cell growth. We have also shown PAK1 ability to up-regulate Snail1, one of the epithelial-mesenchymal transition proteins, and obtained experimental evidence for Snail1 importance in the regulation of cell proliferation. In general, the results obtained in this study demonstrate involvement of PAK1 and Snail1 in the formation of estrogen-independent phenotype of breast cancer cells showing the potential role of both proteins as markers of hormone resistance of breast tumors.

scholarly journals LncRNA-ZFAS1 Induces Epithelial-Mesenchymal Transition of Pancreatic Cancer Cells During Nutrient Deprivation by Promoting AMPK-Mediated Phosphorylation and Stabilization Of ZEB1 Protein

2021 ◽  
Author(s):  
ZHU ZENG ◽  
Shengbo Han ◽  
Yang Wang ◽  
Yan Huang ◽  
Yuhang Hu ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Epithelial Mesenchymal Transition ◽  
Nutrient Deprivation ◽  
Loss Of Function ◽  
Western Blot Assay ◽  
Normal Medium ◽  
Mesenchymal Transition ◽  
Glucose Depletion ◽  
Pancreatic Cancer Cells ◽  
Glutamine Deprivation

Abstract Background: Nutrient deprivation is a distinct feature of the tumor microenvironment that plays a crucial role in various cancers. However, the contribution and regulatory mechanism of nutrient deprivation on metastasis of pancreatic cancer (PC) have not been identified. Methods: PC cells were treated with normal medium, glucose-depletion or glutamine-depletion medium to observe the epithelial-mesenchymal transition (EMT). RT-qPCR and western blot assay were applied to evaluate the alteration of mRNA and protein of zinc finger E-box binding homeobox 1 (ZEB1), a crucial EMT regulator factor. Co-IP assay was utilized for evaluating the interaction between AMP-activated protein kinase (AMPK) and ZEB1. LncRNA microarray was adopted to detect the potential lncRNA, which facilitates the association between AMPK and ZEB1. Gain- and loss-of-function experiments were performed to evaluate the roles of ZNFX1 antisense RNA 1 (ZFAS1) in EMT and metastasis of PC. Results: The present study reveals that nutrient deprivation including glucose and glutamine deprivation significantly induces EMT of PC cells, which is dependent on stabilization of ZEB1. We further discover that nutrient deprivation induces upregulation of lncRNA ZFAS1, which promotes the association between AMPK and ZEB1 to phosphorylate and stabilize ZEB1 protein. Notably, ZEB1 reciprocally promotes the transcription of ZFAS1 by binding to the promoter of ZFAS1, forming feedback with ZFAS1. Consistently, depletion of ZFAS1 obviously inhibits nutrient deprivation-induced EMT of PC cells and lung metastasis of PC in nude mice. Meanwhile, clinical data displays that ZFAS1 is overexpressed in PC tissues and correlated with high expression of ZEB1 and Vimentin (VIM), low expression of E-cadherin (E-cad), as well as poor prognosis in PC patients. Conclusions: Our study implicates that glucose and glutamine deprivation promotes EMT and metastasis of PC through lncRNA-mediated stabilization of ZEB1.

Glaucoma following Infant Lensectomy: 2021 Update

2021 ◽  
Author(s):  
David S. Walton ◽  
Helen H. Yeung
Keyword(s):  
Anterior Chamber ◽  
Clinical Evidence ◽  
Epithelial Mesenchymal Transition ◽  
Tissue Injury ◽  
Loss Of Function ◽  
Mesenchymal Transition ◽  
Responsible Mechanism ◽  
Cell Dispersion ◽  
Aphakic Glaucoma ◽  
Lens Cell

Abstract Purpose To review information pertaining to glaucoma following infant lensectomy surgery and to provide evidence to support the responsible mechanism of this condition. Methods and Results Described risk factors and proposed mechanisms for infantile aphakic glaucoma were assessed. The clinical evidence observed in affected glaucoma patients was analyzed, and evidence of postoperative anterior chamber fibrosis was reviewed and interpreted. Conclusion The review and assessment of laboratory and clinical evidence support the proposal that infantile aphakic glaucoma is caused, in part, by postoperative anterior chamber fibroization related to lens cell dispersion and active epithelial-mesenchymal transition with resultant filtration angle tissue injury and loss of function.

Sign in / Sign up

Export Citation Format

Share Document