Pax3 induces cell aggregation and regulates phenotypic mesenchymal-epithelial interconversion

2002 ◽  
Vol 115 (3) ◽  
pp. 517-529 ◽  
Author(s):  
O'Neil Wiggan ◽  
Marc P. Fadel ◽  
Paul A. Hamel

Paired box-containing transcription factors play fundamental roles in pattern formation during embryonic development of diverse organisms ranging from Drosophila to mammals. Although mutations to Pax3 and other Pax-family genes in both mice and humans result in numerous tissue-specific morphological defects, little is known about the cellular processes that Pax genes regulate. We show that extopic Pax3 expression in two distinct phenotypically mesenchymal mammalian cell lines induces the formation of multi-layered condensed cell aggregates with epithelial characteristics. For one of these lines, we showed further that Pax3-induced cell aggregation is accompanied by specific morphological changes, including a significant reduction in cell size, altered cell shape and dramatic alterations to both membrane and cytoskeleton architecture. In addition to mediating a phenotypic mesenchymal-to-epithelial transition, Pax3 also establishes the conditions in these cells for a subsequent hepatocyte growth factor/scatter factor(HGF/SF)-induced phenotypic epithelial-to-mesenchymal transition. Thus, our data show a novel morphogenetic activity for Pax3 which, when absent in vivo,is predicted to give rise to the observed structural defects in somites and the neural tube during embryonic development.

2021 ◽  
Vol 12 (7) ◽  
Author(s):  
Yu Tian ◽  
Bo Tang ◽  
Chengye Wang ◽  
Yan Wang ◽  
Jiakai Mao ◽  
...  

AbstractOncogenic ubiquitin-specific protease 22 (USP22) is implicated in a variety of tumours; however, evidence of its role and underlying molecular mechanisms in cholangiocarcinoma (CCA) development remains unknown. We collected paired tumour and adjacent non-tumour tissues from 57 intrahepatic CCA (iCCA) patients and evaluated levels of the USP22 gene and protein by qPCR and immunohistochemistry. Both the mRNA and protein were significantly upregulated, correlated with the malignant invasion and worse OS of iCCA. In cell cultures, USP22 overexpression increased CCA cell proliferation and mobility, and induced epithelial-to-mesenchymal transition (EMT). Upon an interaction, USP22 deubiquitinated and stabilized sirtuin-1 (SIRT1), in conjunction with Akt/ERK activation. In implantation xenografts, USP22 overexpression stimulated tumour growth and metastasis to the lungs of mice. Conversely, the knockdown by USP22 shRNA attenuated the tumour growth and invasiveness in vitro and in vivo. Furthermore, SIRT1 overexpression reversed the USP22 functional deficiency, while the knockdown acetylated TGF-β-activated kinase 1 (TAK1) and Akt. Our present study defines USP22 as a poor prognostic predictor in iCCA that cooperates with SIRT1 and facilitates tumour development.


Cancers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1742
Author(s):  
Melysa Fitriana ◽  
Wei-Lun Hwang ◽  
Pak-Yue Chan ◽  
Tai-Yuan Hsueh ◽  
Tsai-Tsen Liao

Head and neck squamous cell carcinomas (HNSCCs) are epithelial malignancies with 5-year overall survival rates of approximately 40–50%. Emerging evidence indicates that a small population of cells in HNSCC patients, named cancer stem cells (CSCs), play vital roles in the processes of tumor initiation, progression, metastasis, immune evasion, chemo-/radioresistance, and recurrence. The acquisition of stem-like properties of cancer cells further provides cellular plasticity for stress adaptation and contributes to therapeutic resistance, resulting in a worse clinical outcome. Thus, targeting cancer stemness is fundamental for cancer treatment. MicroRNAs (miRNAs) are known to regulate stem cell features in the development and tissue regeneration through a miRNA–target interactive network. In HNSCCs, miRNAs act as tumor suppressors and/or oncogenes to modulate cancer stemness and therapeutic efficacy by regulating the CSC-specific tumor microenvironment (TME) and signaling pathways, such as epithelial-to-mesenchymal transition (EMT), Wnt/β-catenin signaling, and epidermal growth factor receptor (EGFR) or insulin-like growth factor 1 receptor (IGF1R) signaling pathways. Owing to a deeper understanding of disease-relevant miRNAs and advances in in vivo delivery systems, the administration of miRNA-based therapeutics is feasible and safe in humans, with encouraging efficacy results in early-phase clinical trials. In this review, we summarize the present findings to better understand the mechanical actions of miRNAs in maintaining CSCs and acquiring the stem-like features of cancer cells during HNSCC pathogenesis.


2021 ◽  
Vol 22 (10) ◽  
pp. 5194
Author(s):  
Paola Pontrelli ◽  
Francesca Conserva ◽  
Rossella Menghini ◽  
Michele Rossini ◽  
Alessandra Stasi ◽  
...  

Diabetic nephropathy (DN) is the most frequent cause of end-stage renal disease. Tubulointerstitial accumulation of lysine 63 (K63)-ubiquitinated (Ub) proteins is involved in the progression of DN fibrosis and correlates with urinary miR-27b-3p downregulation. We explored the renoprotective effect of an inhibitor of K63-Ub (NSC697923), alone or in combination with the ACE-inhibitor ramipril, in vitro and in vivo. Proximal tubular epithelial cells and diabetic DBA/2J mice were treated with NSC697923 and/or ramipril. K63-Ub protein accumulation along with α-SMA, collagen I and III, FSP-1, vimentin, p16INK4A expression, SA-α Gal staining, Sirius Red, and PAS staining were measured. Finally, we measured the urinary albumin to creatinine ratio (uACR), and urinary miR-27b-3p expression in mice. NSC697923, both alone and in association with ramipril, in vitro and in vivo inhibited hyperglycemia-induced epithelial to mesenchymal transition by significantly reducing K63-Ub proteins, α-SMA, collagen I, vimentin, FSP-1 expression, and collagen III along with tubulointerstitial and glomerular fibrosis. Treated mice also showed recovery of urinary miR-27b-3p and restored expression of p16INK4A. Moreover, NSC697923 in combination with ramipril demonstrated a trend in the reduction of uACR. In conclusion, we suggest that selective inhibition of K63-Ub, when combined with the conventional treatment with ACE inhibitors, might represent a novel treatment strategy to prevent the progression of fibrosis and proteinuria in diabetic nephropathy and we propose miR-27b-3p as a biomarker of treatment efficacy.


2021 ◽  
pp. 1-15
Author(s):  
Ping Xu ◽  
Xiao Mo ◽  
Ruixue Xia ◽  
Long Jiang ◽  
Chengfei Zhang ◽  
...  

BACKGROUND: Potassium channels, encoded by more than seventy genes, are cell excitability transmembrane proteins and become evident to play essential roles in tumor biology. OBJECTIVE: The deregulation of potassium channel genes has been related to cancer development and patient prognosis. The objective of this study is to understand the role of potassium channels in lung cancer. METHODS: We examined all potassium channel genes and identified that KCNN4 is the most significantly overexpressed one in lung adenocarcinoma. The role and mechanism of KCNN4 in lung adenocarcinoma were further investigated by in vitro cell and molecular assay and in vivo mouse xenograft models. RESULTS: We revealed that the silencing of KCNN4 significantly inhibits cell proliferation, migration, invasion, and tumorigenicity of lung adenocarcinoma. Further studies showed that knockdown of KCNN4 promotes cell apoptosis, induces cell cycle arrested in the S phase, and is associated with the epithelial to mesenchymal transition (EMT) process. Most importantly, we demonstrated that KCNN4 regulates the progression of lung adenocarcinoma through P13K/AKT and MEK/ERK signaling pathways. The use of inhibitors that targeted AKT and ERK also significantly inhibit the proliferation and metastasis of lung adenocarcinoma cells. CONCLUSIONS: This study investigated the function and mechanism of KCNN4 in lung adenocarcinoma. On this basis, this means that KCNN4 can be used as a tumor marker for lung adenocarcinoma and is expected to become an important target for a potential drug.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Victoria Damerell ◽  
Michael S. Pepper ◽  
Sharon Prince

AbstractSarcomas are complex mesenchymal neoplasms with a poor prognosis. Their clinical management is highly challenging due to their heterogeneity and insensitivity to current treatments. Although there have been advances in understanding specific genomic alterations and genetic mutations driving sarcomagenesis, the underlying molecular mechanisms, which are likely to be unique for each sarcoma subtype, are not fully understood. This is in part due to a lack of consensus on the cells of origin, but there is now mounting evidence that they originate from mesenchymal stromal/stem cells (MSCs). To identify novel treatment strategies for sarcomas, research in recent years has adopted a mechanism-based search for molecular markers for targeted therapy which has included recapitulating sarcomagenesis using in vitro and in vivo MSC models. This review provides a comprehensive up to date overview of the molecular mechanisms that underpin sarcomagenesis, the contribution of MSCs to modelling sarcomagenesis in vivo, as well as novel topics such as the role of epithelial-to-mesenchymal-transition (EMT)/mesenchymal-to-epithelial-transition (MET) plasticity, exosomes, and microRNAs in sarcomagenesis. It also reviews current therapeutic options including ongoing pre-clinical and clinical studies for targeted sarcoma therapy and discusses new therapeutic avenues such as targeting recently identified molecular pathways and key transcription factors.


2016 ◽  
Vol 215 (5) ◽  
pp. 735-747 ◽  
Author(s):  
Andrew T. Schiffmacher ◽  
Vivien Xie ◽  
Lisa A. Taneyhill

During epithelial-to-mesenchymal transitions (EMTs), cells disassemble cadherin-based junctions to segregate from the epithelia. Chick premigratory cranial neural crest cells reduce Cadherin-6B (Cad6B) levels through several mechanisms, including proteolysis, to permit their EMT and migration. Serial processing of Cad6B by a disintegrin and metalloproteinase (ADAM) proteins and γ-secretase generates intracellular C-terminal fragments (CTF2s) that could acquire additional functions. Here we report that Cad6B CTF2 possesses a novel pro-EMT role by up-regulating EMT effector genes in vivo. After proteolysis, CTF2 remains associated with β-catenin, which stabilizes and redistributes both proteins to the cytosol and nucleus, leading to up-regulation of β-catenin, CyclinD1, Snail2, and Snail2 promoter-based GFP expression in vivo. A CTF2 β-catenin–binding mutant, however, fails to alter gene expression, indicating that CTF2 modulates β-catenin–responsive EMT effector genes. Notably, CTF2 association with the endogenous Snail2 promoter in the neural crest is β-catenin dependent. Collectively, our data reveal how Cad6B proteolysis orchestrates multiple pro-EMT regulatory inputs, including CTF2-mediated up-regulation of the Cad6B repressor Snail2, to ensure proper cranial neural crest EMT.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Jeffrey D. Amack

AbstractEpithelial-mesenchymal transition (EMT) refers to a process in which epithelial cells lose apical-basal polarity and loosen cell–cell junctions to take on mesenchymal cell morphologies and invasive properties that facilitate migration through extracellular matrix. EMT—and the reverse mesenchymal-epithelial transition (MET)—are evolutionarily conserved processes that are used throughout embryonic development to drive tissue morphogenesis. During adult life, EMT is activated to close wounds after injury, but also can be used by cancers to promote metastasis. EMT is controlled by several mechanisms that depend on context. In response to cell–cell signaling and/or interactions with the local environment, cells undergoing EMT make rapid changes in kinase and adaptor proteins, adhesion and extracellular matrix molecules, and gene expression. Many of these changes modulate localization, activity, or expression of cytoskeletal proteins that mediate cell shape changes and cell motility. Since cellular changes during EMT are highly dynamic and context-dependent, it is ideal to analyze this process in situ in living organisms. Embryonic development of model organisms is amenable to live time-lapse microscopy, which provides an opportunity to watch EMT as it happens. Here, with a focus on functions of the actin cytoskeleton, I review recent examples of how live in vivo imaging of embryonic development has led to new insights into mechanisms of EMT. At the same time, I highlight specific developmental processes in model embryos—gastrulation in fly and mouse embryos, and neural crest cell development in zebrafish and frog embryos—that provide in vivo platforms for visualizing cellular dynamics during EMT. In addition, I introduce Kupffer’s vesicle in the zebrafish embryo as a new model system to investigate EMT and MET. I discuss how these systems have provided insights into the dynamics of adherens junction remodeling, planar cell polarity signaling, cadherin functions, and cytoskeletal organization during EMT, which are not only important for understanding development, but also cancer progression. These findings shed light on mechanisms of actin cytoskeletal dynamics during EMT, and feature live in vivo imaging strategies that can be exploited in future work to identify new mechanisms of EMT and MET.


2017 ◽  
Vol 233 (3) ◽  
pp. 217-227 ◽  
Author(s):  
Maaike M Roefs ◽  
Françoise Carlotti ◽  
Katherine Jones ◽  
Hannah Wills ◽  
Alexander Hamilton ◽  
...  

Type 2 diabetes (T2DM) is associated with pancreatic islet dysfunction. Loss of β-cell identity has been implicated via dedifferentiation or conversion to other pancreatic endocrine cell types. How these transitions contribute to the onset and progression of T2DM in vivo is unknown. The aims of this study were to determine the degree of epithelial-to-mesenchymal transition occurring in α and β cells in vivo and to relate this to diabetes-associated (patho)physiological conditions. The proportion of islet cells expressing the mesenchymal marker vimentin was determined by immunohistochemistry and quantitative morphometry in specimens of pancreas from human donors with T2DM (n = 28) and without diabetes (ND, n = 38) and in non-human primates at different stages of the diabetic syndrome: normoglycaemic (ND, n = 4), obese, hyperinsulinaemic (HI, n = 4) and hyperglycaemic (DM, n = 8). Vimentin co-localised more frequently with glucagon (α-cells) than with insulin (β-cells) in the human ND group (1.43% total α-cells, 0.98% total β-cells, median; P < 0.05); these proportions were higher in T2DM than ND (median 4.53% α-, 2.53% β-cells; P < 0.05). Vimentin-positive β-cells were not apoptotic, had reduced expression of Nkx6.1 and Pdx1, and were not associated with islet amyloidosis or with bihormonal expression (insulin + glucagon). In non-human primates, vimentin-positive β-cell proportion was larger in the diabetic than the ND group (6.85 vs 0.50%, medians respectively, P < 0.05), but was similar in ND and HI groups. In conclusion, islet cell expression of vimentin indicates a degree of plasticity and dedifferentiation with potential loss of cellular identity in diabetes. This could contribute to α- and β-cell dysfunction in T2DM.


2021 ◽  
Vol 3 (Supplement_2) ◽  
pp. ii9-ii9
Author(s):  
Tamara Lah Turnsek ◽  
Barbara Breznik ◽  
Bernarda Majc ◽  
Metka Novak ◽  
Andrej Porčnik ◽  
...  

Abstract Epithelial-to-mesenchymal transition (EMT) is an essential molecular and cellular process in physiologic processes and invasion of various types of carcinoma and glioblastoma (GBM) cells. EMT is activated and regulated by specific endogenous triggers in complex network of intercellular interactions and signaling pathways. The hallmark of cancer-linked EMT are intermediate states that show notable cell plasticity, characteristic of cancer stem cells (CSCs), including glioblastoma stem cells – GSCs. GSCs resistance to irradiation (IR) and temozolomide (TMZ) chemotherapy is responsible for early relapses, even at distant brain sites. As GSCs are mostly homing to their “niches” as slowly-dividing GSC-subtype, mimicking a proneural-like non- invasive phenotype PN-genotype, we assume that this, by undergoing an EMT-like transition, GSCs are-reprogrammed to an invasive mesenchymal (MES) GBs/GSCs phenotype in a processes, called PMT (1). However, it is not known, if and by which environmental cues within the niche, this transition of GSCs is induced in vivo. In this work, we are presenting the transriptome data obtained when we exposed GSC spheroids to irradiation alone, TMZ alone and to the combined treatment in vitro and compared their differential genetic fingerprints related to EMT/PMT transition to the GSCs PMT transition, when embedded in their natural microenvironment in the GBM organoid model. The differential gene expression upon GSCs therapeutic perturbation (when alone and vs in the tumoroid microenvironment) will reveal the effects of the major candidate genes, associated with micronevironmendt stromal cells and matrix are contributing their observed EMT/PMT transition of GSCs in vivo. •1. Majc, B., Sever, T., Zarić, M, Breznik, B., Turk, B, Lah Turnšek, T. Epithelial- to-mesenchymal transition as the driver of changing carcinoma and glioblastoma microenvironment. DOI: 10.1016/j.bbamcr.2020.118782


2021 ◽  
Author(s):  
Wentao Li ◽  
Ismatullah Soufiany ◽  
Xiao Lyu ◽  
Lin Zhao ◽  
Chenfei Lu ◽  
...  

Abstract Background: Mounting evidences have shown the importance of lncRNAs in tumorigenesis and cancer progression. LBX2-AS1 is an oncogenic lncRNA that has been found abnormally expressed in gastric cancer and lung cancer samples. Nevertheless, the biological function of LBX2-AS1 in glioblastoma (GBM) and potential molecular mechanism are largely unclear. Methods: Relative levels of LBX2-AS1 in GBM samples and cell lines were detected by qRT-PCR and FISH. In vivo and in vitro regulatory effects of LBX2-AS1 on cell proliferation, epithelial-to-mesenchymal transition (EMT) and angiogenesis in GBM were examined through xenograft models and functional experiments, respectively. The interaction between Sp1 and LBX2-AS1 was assessed by ChIP. Through bioinformatic analyses, dual-luciferase reporter assay, RIP and Western blot, the regulation of LBX2-AS1 and miR-491-5p on the target gene leukemia Inhibitory factor (LIF) was identified. Results: LBX2-AS1 was upregulated in GBM samples and cell lines, and its transcription was promoted by binding to the transcription factor Sp1. As a lncRNA mainly distributed in the cytoplasm, LBX2-AS1 upregulated LIF, and activated the LIF/STAT3 signaling by exerting the miRNA sponge effect on miR-491-5p, thus promoting cell proliferation, EMT and angiogenesis in GBM. Besides, LBX2-AS1 was unfavorable to the progression of glioma and the survival. Conclusion: Upregulated by Sp1, LBX2-AS1 promotes the progression of GBM by targeting the miR-491-5p/LIF axis. It is suggested that LBX2-AS1 may be a novel diagnostic biomarker and therapeutic target of GBM.


Sign in / Sign up

Export Citation Format

Share Document