scholarly journals The epithelial-mesenchymal transcription factor SNAI1 represses transcription of the tumor suppressor miRNA let-7 in cancer

2020 ◽  
Author(s):  
H Wang ◽  
E Chirshev ◽  
N Hojo ◽  
T Suzuki ◽  
A Bertucci ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Transcription Factor ◽  
Stem Cell ◽  
Cancer Cells ◽  
Molecular Mechanisms ◽  
Epithelial Mesenchymal Transition ◽  
Tumor Burden ◽  
Cell Phenotype ◽  
Mesenchymal Transition

AbstractWe 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.Novelty and ImpactThis study provides new insight into molecular mechanisms by which EMT transcription factor SNAI1 exerts its pro-stemness effects in cancer cells, demonstrating its potential as a stem cell-directed target for therapy. In vitro and in vivo, mesoporous silica nanoparticle-mediated SNAI1 knockdown resulted in restoration of let-7 miRNA, inhibiting stemness and reducing tumor burden. Our studies validate in vivo nanoparticle-delivered RNAi targeting the SNAI1/let-7 axis as a clinically relevant approach.

scholarly journals The Epithelial–Mesenchymal Transcription Factor SNAI1 Represses Transcription of the Tumor Suppressor miRNA let-7 in Cancer

Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1469
Author(s):  
Hanmin Wang ◽  
Evgeny Chirshev ◽  
Nozomi Hojo ◽  
Tise Suzuki ◽  
Antonella Bertucci ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Stem Cell ◽  
Cancer Cells ◽  
Epithelial Mesenchymal Transition ◽  
Tumor Burden ◽  
Cell Phenotype ◽  
Mesenchymal Transition ◽  
Carcinoma Cell Lines ◽  
Future Work

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.

scholarly journals MiR-149-3p promotes the cisplatin resistance and EMT in ovarian cancer through downregulating TIMP2 and CDKN1A

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Jin Wang ◽  
Lingxia Liu
Keyword(s):  
Ovarian Cancer ◽  
Molecular Mechanisms ◽  
Cisplatin Resistance ◽  
Epithelial Mesenchymal Transition ◽  
Gynecological Cancer ◽  
Gene Expression Omnibus ◽  
Luciferase Assay ◽  
Migration And Invasion ◽  
Mesenchymal Transition

Abstract Background Ovarian cancer (OC), a kind of gynecological cancer, is characterized by high mortality rate, with microRNAs (miRNAs) playing essential roles in it. However, the clinical significance of miRNAs and their molecular mechanisms in OC are mostly unknown. Methods miR-149-3p expression was predicted through Gene Expression Omnibus (GEO) data in OC and confirmed by q-PCR in various OC cells and tissues from patients with different clinical characteristics. Moreover, its roles in terms of proliferation, migration and invasion were measured by CCK-8, colony formation, wound healing and transwell assays in OC cells including cisplatin-resistant and cisplatin-sensitive cells. And its effect on epithelial-mesenchymal transition was also assessed through detecting related protein expression. Additionally, its potential targets were verified by dual luciferase assay and Ago-RIP assay. Finally, its oncogenic functions were explored in vivo. Results In data from GSE79943, GSE131790, and TCGA, miR-149-3p was found to be highly expressed in OC tissues and associated with poor survival. In metastasis and chemoresistant tissues and cisplatin-resistant OC cells, its high expression was confirmed. In terms of tumorigenic effects, miR-149-3p knockdown in cisplatin-resistant OC cells inhibited its cisplatin resistance and other malignant phenotypes, while miR-149-3p overexpression in cisplatin-resistant OC cells led to contrary results. Mechanistically, miR-149-3p targeted 3’UTR of CDKN1A and TIMP2 to function as an oncogenic miRNA. Conclusion In brief, miR-149-3p promoted cisplatin resistance and EMT in OC by downregulating CDKN1A and TIMP2, which might provide a potential therapeutic target for OC treatment.

Complement Component 3 (C3) Is a Mediator of Epithelial-Mesenchymal Transition (EMT)

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 1421-1421
Author(s):  
Min Soon Cho ◽  
Qianghua Hu ◽  
Rajesha Rupaimoole ◽  
Anil Sood ◽  
Vahid Afshar-Kharghan
Keyword(s):  
Ovarian Cancer ◽  
Cancer Cells ◽  
Epithelial Mesenchymal Transition ◽  
Malignant Tumors ◽  
Mouse Embryos ◽  
Ovarian Cancer Cells ◽  
Mesenchymal Transition ◽  
E Cadherin

Abstract We have shown that complement component 3 (C3) is expressed in malignant ovarian epithelial cells and enhances cell proliferation in vitro and tumor growth in vivo. C3 is secreted by cancer cells into the tumor microenvironment and promotes tumor growth through an autocrine loop. To understand the mechanism of upregulation of C3 expression in malignant epithelial cells, we studied the transcriptional regulation of C3, and found that TWIST1, a major regulator of EMT, binds to the C3 promoter and regulates C3 transcription. Knockdown of the TWIST1 gene reduced C3 mRNA, and TWIST1 overexpression increased C3 mRNA. TWIST1 promotes epithelial-mesenchymal transition (EMT) during normal development and in metastasis of malignant tumors. An important marker of EMT is a reduction in the surface expression of E-cadherin on cells facilitating migration and invasion of these cells. TWIST1 is a transcriptional repressor of E-cadherin; and because TWIST1 increases C3 expression, we investigated whether C3 is also a negative regulator of E-cadherin expression. We overexpressed C3 in ovarian cancer cells by stable transduction of lentivirus carrying C3 cDNA. Overexpression of C3 was associated with 32% reduction in the expression of E-cadherin resulting in enhanced migration ability of cells by 2.3 folds and invasiveness by 1.75 folds, as compared to control cells transduced with control lentivirus. To investigate whether TWIST1-induced reduction in E-cadherin is C3-mediated or not, we studied the effect of TWIST1 overexpression simultaneous with C3 knockdown in ovarian cancer cells. Overexpression of TWIST1 alone resulted in 70% reduction in E-cadherin mRNA and this was completely reversed after simultaneous C3 knockdown in these cells. To investigate the correlation between C3 and TWIST1 in vivo, we studied the co-expression of these two proteins in mouse embryos (physiologic EMT) and in malignant tumors (pathologic EMT). Given the role of EMT in embryogenesis we immunostained mouse embryos at different stages of development, using antibodies against TWIST1 or C3. Transverse section of 9.5-day post-coitum (9.5dpc) mouse embryos showed co-expression of TWIST1 and C3 in otocyst (ot) and hindbrain (hb) of neural crest. In the whole-mounted 11.5dpc mouse embryos, C3 and TWIST1 were co-expressed in limb buds. Given the role of EMT in malignancy, tumors induced in mice after intraperitoneal injection of murine ovarian cancer cells were resected and immunostained for C3 and TWIST1 proteins. TWIST1 and C3 co-localized at tumor edges, where EMT and tumor cells migration occur. Taken together, these data provide evidence that TWIST1 regulates C3 expression, and C3 promotes EMT through E-cadherin. Disclosures No relevant conflicts of interest to declare.

scholarly journals SPR965, a Dual PI3K/mTOR Inhibitor, as a Targeted Therapy in Ovarian Cancer

2021 ◽  
Vol 10 ◽  
Author(s):  
Arthur-Quan Tran ◽  
Stephanie A. Sullivan ◽  
Leo Li-Ying Chan ◽  
Yajie Yin ◽  
Wenchuan Sun ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Tumor Growth ◽  
Cancer Cells ◽  
Epithelial Mesenchymal Transition ◽  
Transition Process ◽  
Ovarian Cancer Cells ◽  
Serous Ovarian Cancer ◽  
Mesenchymal Transition

SPR965 is an inhibitor of PI3K and mTOR C1/C2 and has demonstrated anti-tumorigenic activity in a variety of solid tumors. We sought to determine the effects of SPR965 on cell proliferation and tumor growth in human serous ovarian cancer cell lines and a transgenic mouse model of high grade serous ovarian cancer (KpB model) and identify the underlying mechanisms by which SPR965 inhibits cell and tumor growth. SPR965 showed marked anti-proliferative activity by causing cell cycle arrest and inducing cellular stress in ovarian cancer cells. Treatment with SPR965 significantly inhibited tumor growth in KpB mice, accompanied by downregulation of Ki67 and VEGF and upregulation of Bip expression in ovarian tumors. SPR965 also inhibited adhesion and invasion through induction of the epithelial–mesenchymal transition process. As expected, downregulation of phosphorylation of AKT and S6 was observed in SPR965-treated ovarian cancer cells and tumors. Our results suggest that SPR965 has significant anti-tumorigenic effects in serous ovarian cancer in vitro and in vivo. Thus, SPR965 should be evaluated as a promising targeted agent in future clinical trials of ovarian cancer.

scholarly journals Exosomes in ovarian cancer ascites promote epithelial–mesenchymal transition of ovarian cancer cells by delivery of miR-6780b-5p

2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Jing Cai ◽  
Lanqing Gong ◽  
Guodong Li ◽  
Jing Guo ◽  
Xiaoqing Yi ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Cancer Cells ◽  
Tumor Metastasis ◽  
Cancer Metastasis ◽  
Epithelial Mesenchymal Transition ◽  
Ovarian Cancer Cells ◽  
Specific Mechanism ◽  
Mesenchymal Transition

AbstractThe poor prognosis of ovarian cancer is mainly due to metastasis, and the specific mechanism underlying ovarian cancer metastasis is not clear. Ascites-derived exosomes (ADEs) play an important role in the progression of ovarian cancer, but the mechanism is unknown. Here, we found that ADEs promoted ovarian cancer metastasis not only in vitro but also in vivo. This promotive function was based on epithelial–mesenchymal transition (EMT) of ovarian cancer cells. Bioinformatics analysis of RNA sequencing microarray data indicated that miR-6780b-5p may be the key microRNA (miRNA) in ADEs that facilitates cancer metastasis. Moreover, the expression of exosomal miR-6780b-5p correlated with tumor metastasis in ovarian cancer patients. miR-6780b-5p overexpression promoted and miR-6780b-5p downregulation suppressed EMT of ovarian cancer cells. These results suggest that ADEs transfer miR-6780b-5p to ovarian cancer cells, promoting EMT and finally facilitating ovarian cancer metastasis.

scholarly journals Toxicarioside O Inhibits Cell Proliferation and Epithelial-Mesenchymal Transition by Downregulation of Trop2 in Lung Cancer Cells

2021 ◽  
Vol 10 ◽  
Author(s):  
Wu-Ping Zheng ◽  
Feng-Ying Huang ◽  
Shu-Zhen Dai ◽  
Jin-Yan Wang ◽  
Ying-Ying Lin ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Cell Proliferation ◽  
Cancer Cells ◽  
Molecular Mechanisms ◽  
Anticancer Agent ◽  
Epithelial Mesenchymal Transition ◽  
Lung Cancer Cells ◽  
Mesenchymal Transition

Toxicarioside O (TCO), a natural product derived from Antiaris toxicaria, has been identified to be a promising anticancer agent. In this study, we aimed to investigate the effect of TCO on the proliferation and epithelial-mesenchymal transition (EMT) of lung cancer cells and its molecular mechanisms. Here, we indicated that TCO inhibits the proliferation of lung cancer cells both in vitro and in vivo. Our results demonstrated that TCO induces apoptosis in lung cancer cells. Moreover, we found that TCO suppresses EMT program and inhibits cell migration in vitro. Mechanistically, TCO decreases the expression of trophoblast cell surface antigen 2 (Trop2), resulting in inhibition of the PI3K/Akt pathway and EMT program. Overexpression of Trop2 rescues TCO-induced inhibition of cell proliferation and EMT. Our findings demonstrate that TCO markedly inhibits cell proliferation and EMT in lung cancer cells and provides guidance for its drug development.

scholarly journals Human umbilical cord mesenchymal stem cell-derived exosomal miR-27b attenuates subretinal fibrosis via suppressing epithelial–mesenchymal transition by targeting HOXC6

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Dongli Li ◽  
Junxiu Zhang ◽  
Zijia Liu ◽  
Yuanyuan Gong ◽  
Zhi Zheng
Keyword(s):  
Stem Cell ◽  
Mesenchymal Stem Cell ◽  
Umbilical Cord ◽  
Mechanism Of Action ◽  
Epithelial Mesenchymal Transition ◽  
Human Umbilical Cord ◽  
Mesenchymal Transition ◽  
Rpe Cells ◽  
Subretinal Fibrosis

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.

scholarly journals A novel homeostatic loop of sorcin drives paclitaxel-resistance and malignant progression via Smad4/ZEB1/miR-142-5p in human ovarian cancer

Oncogene ◽  
2021 ◽  
Author(s):  
Jinguo Zhang ◽  
Wencai Guan ◽  
Xiaolin Xu ◽  
Fanchen Wang ◽  
Xin Li ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Calcium Binding ◽  
Molecular Mechanisms ◽  
Epithelial Mesenchymal Transition ◽  
Malignant Progression ◽  
Bioinformatics Analyses ◽  
Aberrant Expression ◽  
Mesenchymal Transition ◽  
E Box

AbstractThe primary chemotherapy of ovarian cancer (OC) often acquires chemoresistance. Sorcin (SRI), a soluble resistance-related calcium-binding protein, has been reported to be an oncogenic protein in cancer. However, the molecular mechanisms of SRI regulation and the role and aberrant expression of SRI in chemoresistant OC remain unclear. Here, we identified SRI as a key driver of paclitaxel (PTX)-resistance and explored its regulatory mechanism. Using transcriptome profiles, qRT-PCR, proteomics, Western blot, immunohistochemistry, and bioinformatics analyses, we found that SRI was overexpressed in PTX-resistant OC cells and the overexpression of SRI was related to the poor prognosis of patients. SRI was a key molecule required for growth, migration, and PTX-resistance in vitro and in vivo and was involved in epithelial–mesenchymal transition (EMT) and stemness. Mechanistic studies showed that miR-142-5p directly bound to the 3ʹ-UTR of SRI to suppress its expression, whereas a transcription factor zinc-finger E-box binding homeobox 1 (ZEB1) inhibited the transcription of miR-142-5p by directly binding to the E-box fragment in the miR-142 promoter region. Furthermore, ZEB1 was negatively regulated by SRI which physically interacted with Smad4 to block its translocation from the cytosol to the nucleus. Taken together, our findings unveil a novel homeostatic loop of SRI that drives the PTX-resistance and malignant progression via Smad4/ZEB1/miR-142-5p in human OC. Targeting this SRI/Smad4/ZEB1/miR-142-5p loop may reverse the PTX-resistance.

scholarly journals Tumor- and osteoclast-derived NRP2 in prostate cancer bone metastases

Bone Research ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Navatha Shree Polavaram ◽  
Samikshan Dutta ◽  
Ridwan Islam ◽  
Arup K. Bag ◽  
Sohini Roy ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Bone Metastasis ◽  
Cancer Cells ◽  
Molecular Mechanisms ◽  
Osteoclast Differentiation ◽  
Potential Effect ◽  
Tumor Burden ◽  
Bone Lesions ◽  
Prostate Cancer Cells

AbstractUnderstanding the role of neuropilin 2 (NRP2) in prostate cancer cells as well as in the bone microenvironment is pivotal in the development of an effective targeted therapy for the treatment of prostate cancer bone metastasis. We observed a significant upregulation of NRP2 in prostate cancer cells metastasized to bone. Here, we report that targeting NRP2 in cancer cells can enhance taxane-based chemotherapy with a better therapeutic outcome in bone metastasis, implicating NRP2 as a promising therapeutic target. Since, osteoclasts present in the tumor microenvironment express NRP2, we have investigated the potential effect of targeting NRP2 in osteoclasts. Our results revealed NRP2 negatively regulates osteoclast differentiation and function in the presence of prostate cancer cells that promotes mixed bone lesions. Our study further delineated the molecular mechanisms by which NRP2 regulates osteoclast function. Interestingly, depletion of NRP2 in osteoclasts in vivo showed a decrease in the overall prostate tumor burden in the bone. These results therefore indicate that targeting NRP2 in prostate cancer cells as well as in the osteoclastic compartment can be beneficial in the treatment of prostate cancer bone metastasis.

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