SUMO E3 ligase CBX4 regulates hTERT-mediated transcription of CDH1 and promotes breast cancer cell migration and invasion

hTERT, the catalytic component of the human telomerase enzyme, is regulated by post-translational modifications, like phosphorylation and ubiquitination by multiple proteins which remarkably affects the overall activity of the enzyme. Here we report that hTERT gets SUMOylated by SUMO1 and polycomb protein CBX4 acts as the SUMO E3 ligase of hTERT. hTERT SUMOylation positively regulates its telomerase activity which can be inhibited by SENP3-mediated deSUMOylation. Interestingly, we have established a new role of hTERT SUMOylation in the repression of E-cadherin gene expression and consequent triggering on the epithelial-mesenchymal-transition (EMT) program in breast cancer cells. We also observed that catalytically active CBX4, leads to retention of hTERT/ZEB1 complex onto E-cadherin promoter leading to its repression through hTERT-SUMOylation. Further through wound healing and invasion assays in breast cancer cells, we showed the tumor promoting ability of hTERT was significantly compromised upon overexpression of SUMO-defective mutant of hTERT. Thus our findings establish a new post-translational modification of hTERT which on one hand is involved in telomerase activity maintenance and on the other hand plays a crucial role in the regulation of gene expression thereby promoting migration and invasion of breast cancer cells.

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FBXL10 promotes EMT and metastasis of breast cancer cells via regulating the acetylation and transcriptional activity of SNAI1

Cell Death Discovery ◽

10.1038/s41420-021-00722-7 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Yangyang Yang ◽

Binggong Zhao ◽

Linlin Lv ◽

Yuxi Yang ◽

Shujing Li ◽

...

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Epithelial Mesenchymal Transition ◽

Migration And Invasion ◽

Bioinformatics Analyses ◽

Positive Role ◽

Mesenchymal Transition ◽

E Cadherin

AbstractF-box and leucine-rich repeat protein 10 (FBXL10) has been reported to play a regulatory role in the initiation and development of breast cancer. Bioinformatics analyses revealed that FBXL10 may involve in the process of cytoskeleton organization. This research aimed to investigate the function of FBXL10 in epithelial-mesenchymal transition (EMT) and metastasis of breast cancer, and tried to reveal the molecular mechanism involved in this issue. Functional experiments in vitro revealed that FBXL10 promoted the migration and invasion of breast cancer cells through inhibiting E-cadherin expression and inducing EMT. Mechanical studies revealed that FBXL10 could specifically interact with SNAI1, but not Slug or ZEB1. And it promoted the transcriptional repression activity of SNAI1 on CDH1 in breast cancer cells. Furthermore, FBXL10 had a positive role for the deacetylation of SNAI1 by facilitating the interaction between SNAI1 and HDAC1, a dominating deacetylase of SNAI1. And the deacetylated SNAI1 showed a more suppressive ability to inhibit the transcription of E-cadherin. Moreover, mouse models were also conducted to confirm the effect of FBXL10 on the lung metastasis of breast cancer in vivo. Totally, our data revealed that FBXL10 served as a pro-metastatic factor in breast cancer via repressing the expression of E-cadherin and inducing EMT. It may provide a novel regulatory axis in the EMT of breast cancer.

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miR-448 inhibits the epithelial-mesenchymal transition in breast cancer cells by directly targeting the E-cadherin repressor ZEB1/2

Experimental Biology and Medicine ◽

10.1177/1535370218754848 ◽

2018 ◽

Vol 243 (5) ◽

pp. 473-480 ◽

Cited By ~ 17

Author(s):

Peng Ma ◽

Kan Ni ◽

Jing Ke ◽

Wenyi Zhang ◽

Ying Feng ◽

...

Keyword(s):

Breast Cancer ◽

Cell Proliferation ◽

Cell Migration ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Epithelial Mesenchymal Transition ◽

Migration And Invasion ◽

Rt Pcr ◽

Mesenchymal Transition ◽

E Cadherin

Recently, accumulating evidence provides that dysregulation of microRNAs (miRNAs) is considered to play vital roles in tumor progression. Based on microRNA arrays, we found that microRNA-448 (miR-448) was significantly downregulated in breast cancer tissue specimens. In our study, we were in an effort to clarify the function, the direct target gene, and the molecular mechanisms of miR-448 in breast cancer. By quantitative RT–PCR, we analyzed the expression of miR-448 in 16 patients with BC. Overexpression of miR-448 was established by transfecting miR-448-mimics into MDA-MB-231 and MCF-7 cells, methyl thiazolyl- tetrazolium and colony formation assays were performed to evaluate its effects on cell proliferation. We also performed cell migration and invasion assays in breast cells overexpressing miRNA-448. All the results indicated that overexpression of miR-448 in breast cancer cells markedly suppressed cell proliferation, migration, and invasion. Through the quantitative RT–PCR and Western Blots, we also evaluated epithelial–mesenchymal transition. We found that overexpression of miR-448 also downregulated the expression of vimentin, a well-known mesenchymal marker. Meanwhile, the epithelial marker E-cadherin was unregulated, suggesting that miR-448 inhibited epithelial–mesenchymal transition . Bioinformatics assay coupled with Western Blot and luciferase assays revealed that miR-448 directly binds to the 3′UTR of E-cadherin repressor ZEB1/2, resulting in suppression of epithelial–mesenchymal transition in breast cancer cells. Impact statement In our study, we revealed that miR-448 played a vital role in breast cancer development and we also uncovered the mechanisms of it. Following is the short description of the main findings: miR-448 is downregulated in BC. miR-448 regulates cell proliferation, migration, and invasion in BC. miR-448 specifically regulates ZEB1/2 through binding to the 3′UTR in BC cells. miR-448 inhibits cell migration, invasion, and EMT by targeting to the 3′UTR of ZEB1/2.

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A Ca2+-ATPase Regulates E-cadherin Biogenesis and Epithelial-Mesenchymal Transition in Breast Cancer Cells

10.1101/379586 ◽

2018 ◽

Cited By ~ 2

Author(s):

Donna K. Dang ◽

Monish Ram Makena ◽

José P. Llongueras ◽

Hari Prasad ◽

Myungjun Ko ◽

...

Keyword(s):

Breast Cancer ◽

Gene Expression ◽

Cell Adhesion ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Epithelial Mesenchymal Transition ◽

Metastatic Cancer ◽

Benign Tumors ◽

Mesenchymal Transition ◽

E Cadherin

AbstractProgression of benign tumors to invasive, metastatic cancer is accompanied by the epithelial to mesenchymal transition (EMT), characterized by loss of the cell-adhesion protein E-cadherin. Although silencing mutations and transcriptional repression of the E-cadherin gene have been widely studied, not much is known about post-translational regulation of E-cadherin in tumors. We show that E-cadherin is tightly co-expressed with the secretory pathway Ca2+-ATPase isoform 2, SPCA2 (ATP2C2), in breast tumors. Loss of SPCA2 impairs surface expression of E-cadherin and elicits mesenchymal gene expression through disruption of cell adhesion in tumorspheres and downstream Hippo-YAP signaling. Conversely, ectopic expression of SPCA2 in triple negative breast cancer (TNBC) elevates baseline Ca2+ and YAP phosphorylation, enhances post-translational expression of E-cadherin, and suppresses mesenchymal gene expression. Thus, loss of SPCA2 phenocopies loss of E-cadherin in the Hippo signaling pathway and EMT-MET transitions, consistent with a functional role for SPCA2 in E-cadherin biogenesis. Furthermore, we show that SPCA2 suppresses invasive phenotypes, including cell migration in vitro and tumor metastasis in vivo. Based on these findings, we propose that SPCA2 functions as a key regulator of EMT and may be a potential therapeutic target for treatment of metastatic cancer.ImplicationsPost-translational control of E-cadherin and the Hippo pathway by calcium signaling regulates epithelial mesenchymal transition in breast cancer cells.

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Mummy Induces Apoptosis Through Inhibiting of Epithelial-Mesenchymal Transition (EMT) in Human Breast Cancer Cells

Galen Medical Journal ◽

10.31661/gmj.v9i0.1812 ◽

2020 ◽

Vol 9 ◽

pp. 1812

Author(s):

Solmaz Rahmani Barouji ◽

Arman Shahabi ◽

Mohammadali Torbati ◽

Seyyed Mohammad Bagher Fazljou ◽

Ahmad Yari Khosroushahi

Keyword(s):

Breast Cancer ◽

Gene Expression ◽

Anticancer Activity ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Epithelial Mesenchymal Transition ◽

Control Group ◽

Mrna Levels ◽

Mesenchymal Transition ◽

Mcf 7

Background: Mummy (Iranian pure shilajit) is a remedy with possessing anti-inflammatory, antioxidant and anticancer activities. This study aimed to examine mummy effects on epithelial-mesenchymal transition (EMT) and invasiveness of MCF-7 and MDA-MB-231 breast cancer (BC) cell lines with underlying its mechanism. Materials and Methods: The dose-dependent inhibitory effect of the mummy on cell proliferation in vitro was determined using the MTT assay. Flow cytometry and 4’,6-diamidino-2-phenylindole dihydrochloride staining were respectively used for quantitative and qualitative analysis of cellular apoptosis, and gene expression analysis was conducted using real-time PCR. Results: MDA-MB-231 showed more sensitivity than the MCF-7 cell line to the anticancer activity of mummy, while mummy did not exhibit significant cell cytotoxicity against human normal cells (MCF-10A). The gene expression profile demonstrated a significant decrease in TGF-β1, TGF-βR1, TWIST1, NOTCH1, CTNNB1, SRC along with an increase in E-cadherin mRNA levels in mummy treated cells compared to the untreated control group (P≤0.05). Conclusion: Mummy triggers inhibition of EMT and metastasis in breast cancer cells mainly through the downregulation of TGFβ1 activity, and more studies required to find its specific anticancer activity with details. [GMJ.2020;9:e1812]

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