scholarly journals Epithelial Cell Rests of Malassez Contain Unique Stem Cell Populations Capable of Undergoing Epithelial–Mesenchymal Transition

2012 ◽  
Vol 21 (11) ◽  
pp. 2012-2025 ◽  
Author(s):  
Jimin Xiong ◽  
Krzysztof Mrozik ◽  
Stan Gronthos ◽  
P. Mark Bartold
2019 ◽  
Author(s):  
Karen Dunbar ◽  
Asta Valanciute ◽  
Vidya Rajasekaran ◽  
Thomas Jamieson ◽  
Paz Freile Vinuela ◽  
...  

ABSTRACTAspirin reduces the incidence and mortality of colorectal cancer (CRC). Wnt signalling drives CRC development from initiation to progression through regulation of epithelial-mesenchymal transition (EMT) and cancer stem cell populations (CSC). Here, we investigated whether aspirin can rescue these pro-invasive phenotypes associated with CRC progression in Wnt-driven human and mouse intestinal organoids. Aspirin rescues the Wnt-driven cystic organoid phenotype by promoting budding in mouse and human Apc deficient organoids, which is paralleled by decreased stem cell marker expression. Aspirin-mediated Wnt inhibition in ApcMin/+ mice is associated with EMT inhibition and decreased cell migration, invasion and motility in CRC cell lines. Chemical Wnt activation induces EMT and stem-like alterations in CRC cells, which are rescued by aspirin. Aspirin increases expression of the Wnt antagonist Dickkopf-1 (DKK-1) in CRC cells and organoids derived from FAP patients. We provide evidence of phenotypic biomarkers of aspirin response with an increased epithelial and reduced stem-like state mediated by an increase in DKK-1. Thus we highlight a novel mechanism of aspirin-mediated Wnt inhibition and potential phenotypic and molecular biomarkers for trials.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Dongli Li ◽  
Junxiu Zhang ◽  
Zijia Liu ◽  
Yuanyuan Gong ◽  
Zhi Zheng

Abstract Background and aim Subretinal fibrosis resulting from neovascular age-related macular degeneration (nAMD) is one of the major causes of serious and irreversible vision loss worldwide, and no definite and effective treatment exists currently. Retinal pigmented epithelium (RPE) cells are crucial in maintaining the visual function of normal eyes and its epithelial–mesenchymal transition (EMT) is associated with the pathogenesis of subretinal fibrosis. Stem cell-derived exosomes have been reported to play a crucial role in tissue fibrosis by transferring their molecular contents. This study aimed to explore the effects of human umbilical cord-derived mesenchymal stem cell exosomes (hucMSC-Exo) on subretinal fibrosis in vivo and in vitro and to investigate the anti-fibrotic mechanism of action of hucMSC-Exo. Methods In this study, human umbilical cord-derived mesenchymal stem cells (hucMSCs) were successfully cultured and identified, and exosomes were isolated from the supernatant by ultracentrifugation. A laser-induced choroidal neovascularization (CNV) and subretinal fibrosis model indicated that the intravitreal administration of hucMSC-Exo effectively alleviated subretinal fibrosis in vivo. Furthermore, hucMSC-Exo could efficaciously suppress the migration of retinal pigmented epithelial (RPE) cells and promote the mesenchymal–epithelial transition by delivering miR-27b-3p. The latent binding of miR-27b-3p to homeobox protein Hox-C6 (HOXC6) was analyzed by bioinformatics prediction and luciferase reporter assays. Results This study showed that the intravitreal injection of hucMSC-Exo effectively ameliorated laser-induced CNV and subretinal fibrosis via the suppression of epithelial–mesenchymal transition (EMT) process. In addition, hucMSC-Exo containing miR-27b repressed the EMT process in RPE cells induced by transforming growth factor-beta2 (TGF-β2) via inhibiting HOXC6 expression. Conclusions The present study showed that HucMSC-derived exosomal miR-27b could reverse the process of EMT induced by TGF-β2 via inhibiting HOXC6, indicating that the exosomal miR-27b/HOXC6 axis might play a vital role in ameliorating subretinal fibrosis. The present study proposed a promising therapeutic agent for treating ocular fibrotic diseases and provided insights into the mechanism of action of hucMSC-Exo on subretinal fibrosis.


Tumor Biology ◽  
2020 ◽  
Vol 42 (12) ◽  
pp. 101042832097943
Author(s):  
Natalia Ospina-Muñoz ◽  
Jean-Paul Vernot

The interleukin-8 is an important regulator of the tumor microenvironment, promoting the epithelial–mesenchymal transition and the acquisition of stem-like cell properties in cancer cells. The tumorsphere-formation assay has been used for the identification of cancer stem cell. Interleukin-8 induces the formation of larger tumorspheres in Michigan Cancer Foundation-7 (MCF-7) cells, suggesting cancer stem cell enrichment. In this work, we aimed to study the phenotypic and functional characteristics of the cells present within the tumorspheres of MCF-7 cells previously treated with interleukin-8. MCF-7 cells treated for 5 days or not with this cytokine were further cultivated in ultralow attachment plates for another 5 days to allow tumorspheres formation. We showed that the enhanced sphere formation by MCF-7 cells was not a consequence of higher cell proliferation by interleukin-8 stimulation. Despite maintaining an epithelial–mesenchymal transition phenotype with the presence of epithelial and mesenchymal markers, basic stemness properties were impaired in tumorspheres and in those treated with interleukin-8, while others were increased. Self-renewal capacity was increased in interleukin-8-treated cells only in the first generation of tumorspheres but was not sustained in consecutive assays. Accordingly, self-renewal and reprogramming gene expression, differentiation capacity to adipocytes, and clonogenicity were also impaired. We showed also that tumorspheres were enriched in differentiated luminal cells (EpCAM+/CD49f−). Nevertheless, cells were more quiescent and maintain a partial epithelial–mesenchymal transition, consistent with their increased resistance to Paclitaxel and Doxorubicin. They also presented higher migration and interleukin-8-directed invasion. Therefore, the breast cancer cell line MCF-7, having a low stemness index, might partially acquire some stem-like cell attributes after interleukin-8 stimulation, increasing its aggressiveness.


Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1469
Author(s):  
Hanmin Wang ◽  
Evgeny Chirshev ◽  
Nozomi Hojo ◽  
Tise Suzuki ◽  
Antonella Bertucci ◽  
...  

We aimed to determine the mechanism of epithelial–mesenchymal transition (EMT)-induced stemness in cancer cells. Cancer relapse and metastasis are caused by rare stem-like cells within tumors. Studies of stem cell reprogramming have linked let-7 repression and acquisition of stemness with the EMT factor, SNAI1. The mechanisms for the loss of let-7 in cancer cells are incompletely understood. In four carcinoma cell lines from breast cancer, pancreatic cancer, and ovarian cancer and in ovarian cancer patient-derived cells, we analyzed stem cell phenotype and tumor growth via mRNA, miRNA, and protein expression, spheroid formation, and growth in patient-derived xenografts. We show that treatment with EMT-promoting growth factors or SNAI1 overexpression increased stemness and reduced let-7 expression, while SNAI1 knockdown reduced stemness and restored let-7 expression. Rescue experiments demonstrate that the pro-stemness effects of SNAI1 are mediated via let-7. In vivo, nanoparticle-delivered siRNA successfully knocked down SNAI1 in orthotopic patient-derived xenografts, accompanied by reduced stemness and increased let-7 expression, and reduced tumor burden. Chromatin immunoprecipitation demonstrated that SNAI1 binds the promoters of various let-7 family members, and luciferase assays revealed that SNAI1 represses let-7 transcription. In conclusion, the SNAI1/let-7 axis is an important component of stemness pathways in cancer cells, and this study provides a rationale for future work examining this axis as a potential target for cancer stem cell-specific therapies.


2021 ◽  
Vol 2 (3) ◽  
pp. 100751
Author(s):  
Yuefeng Li ◽  
Kiran Nakka ◽  
Thomas Olender ◽  
Philippe Gingras-Gelinas ◽  
Matthew Man-Kin Wong ◽  
...  

2006 ◽  
Vol 28 (1-2) ◽  
pp. 34-48 ◽  
Author(s):  
Tania O. Alexson ◽  
Seiji Hitoshi ◽  
Brenda L. Coles ◽  
Alan Bernstein ◽  
Derek van der Kooy

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Tetsu Hayashida ◽  
Hiromitsu Jinno ◽  
Yuko Kitagawa ◽  
Masaki Kitajima

Epithelial-mesenchymal transition (EMT) is a multistep process in which cells acquire molecular alterations such as loss of cell-cell junctions and restructuring of the cytoskeleton. There is an increasing understanding that this process may promote breast cancer progression through promotion of invasive and metastatic tumor growth. Recent observations imply that there may be a cross-talk between EMT and cancer stem cell properties, leading to enhanced tumorigenicity and the capacity to generate heterogeneous tumor cell populations. Here, we review the experimental and clinical evidence for the involvement of EMT in cancer stem cell theory, focusing on the common characteristics of this phenomenon.


Oncogene ◽  
2013 ◽  
Vol 33 (32) ◽  
pp. 4123-4131 ◽  
Author(s):  
E Bessède ◽  
C Staedel ◽  
L A Acuña Amador ◽  
P H Nguyen ◽  
L Chambonnier ◽  
...  

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