A Bioinformatic Pipeline Places STAT5A as a miR-650 Target in Poorly Differentiated Aggressive Breast Cancer

Breast cancer (BRCA) is a leading cause of mortality among women. Tumors often acquire aggressive features through genomic aberrations affecting cellular programs, e.g., the epithelial to mesenchymal transition (EMT). EMT facilitates metastasis leading to poor prognosis. We previously observed a correlation between an amplification of miR-650 (Amp-650) and EMT features in BRCA samples isolated from Mexican patients. In this study, we explored the cBioportal database aiming to extend that observation and better understand the importance of Amp-650 for BRCA aggressiveness. We found that Amp-650 is more frequent in aggressive molecular subtypes of BRCA, as well as in high grade poorly differentiated tumors, which we confirmed in an external miRNA expression database. We performed differential expression analysis on samples harboring Amp-650, taking advantage of gene target prediction tools and tumor suppressor gene databases to mine several hundreds of differentially underexpressed genes. We observed STAT5A as a likely putative target gene for miR-650 in aggressive poorly differentiated BRCA. Samples with both Amp-650 and low expression of STAT5A had less overall survival than samples with either or none of the alterations. No target gene has been described for miR-650 in BRCA, thus, this bioinformatic study provides valuable information that should be corroborated experimentally.

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Targeting miRNA by tunable small molecule binders: peptidic aminosugar mediated interference in miR-21 biogenesis reverts epithelial to mesenchymal transition

MedChemComm ◽

10.1039/c8md00092a ◽

2018 ◽

Vol 9 (7) ◽

pp. 1147-1154 ◽

Cited By ~ 6

Author(s):

Arpita Ghosh ◽

Natalya Degyatoreva ◽

Casey Kukielski ◽

Sandra Story ◽

Sayantan Bhaduri ◽

...

Keyword(s):

Breast Cancer ◽

Tumor Suppressor ◽

Tumor Suppressor Gene ◽

Small Molecule ◽

Epithelial To Mesenchymal Transition ◽

Suppressor Gene ◽

Mesenchymal Transition ◽

Malignant Behavior

miR21, a potent regulator of the tumor suppressor gene PTEN, can be silenced to reverse EMT providing an attractive target for abrogating the malignant behavior of breast cancer.

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Proteomic Analysis of Zeb1 Interactome in Breast Carcinoma Cells

Molecules ◽

10.3390/molecules26113143 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3143

Author(s):

Sergey E. Parfenyev ◽

Sergey V. Shabelnikov ◽

Danila Y. Pozdnyakov ◽

Olga O. Gnedina ◽

Leonid S. Adonin ◽

...

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Epithelial To Mesenchymal Transition ◽

Critical Role ◽

Malignant Neoplasm ◽

Malignant Neoplasms ◽

Breast Cancer Patients ◽

Survival Prognosis ◽

Mesenchymal Transition ◽

Wide Range

Breast cancer is the most frequently diagnosed malignant neoplasm and the second leading cause of cancer death among women. Epithelial-to-mesenchymal Transition (EMT) plays a critical role in the organism development, providing cell migration and tissue formation. However, its erroneous activation in malignancies can serve as the basis for the dissemination of cancer cells and metastasis. The Zeb1 transcription factor, which regulates the EMT activation, has been shown to play an essential role in malignant transformation. This factor is involved in many signaling pathways that influence a wide range of cellular functions via interacting with many proteins that affect its transcriptional functions. Importantly, the interactome of Zeb1 depends on the cellular context. Here, using the inducible expression of Zeb1 in epithelial breast cancer cells, we identified a substantial list of novel potential Zeb1 interaction partners, including proteins involved in the formation of malignant neoplasms, such as ATP-dependent RNA helicase DDX17and a component of the NURD repressor complex, CTBP2. We confirmed the presence of the selected interactors by immunoblotting with specific antibodies. Further, we demonstrated that co-expression of Zeb1 and CTBP2 in breast cancer patients correlated with the poor survival prognosis, thus signifying the functionality of the Zeb1–CTBP2 interaction.

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Epigenetic Modulation of SPCA2 Reverses Epithelial to Mesenchymal Transition in Breast Cancer Cells

Cancers ◽

10.3390/cancers13020259 ◽

2021 ◽

Vol 13 (2) ◽

pp. 259

Author(s):

Monish Ram Makena ◽

Myungjun Ko ◽

Donna Kimberly Dang ◽

Rajini Rao

Keyword(s):

Breast Cancer ◽

Secretory Pathway ◽

Histone Deacetylase Inhibitors ◽

Epithelial To Mesenchymal Transition ◽

Molecular Subtype ◽

Survival Prognosis ◽

Mesenchymal Transition ◽

Tumor Cell Migration ◽

Canonical Wnt

The secretory pathway Ca2+-ATPase SPCA2 is a tumor suppressor in triple receptor negative breast cancer (TNBC), a highly aggressive molecular subtype that lacks tailored treatment options. Low expression of SPCA2 in TNBC confers poor survival prognosis in patients. Previous work has established that re-introducing SPCA2 to TNBC cells restores basal Ca2+ signaling, represses mesenchymal gene expression, mitigates tumor migration in vitro and metastasis in vivo. In this study, we examined the effect of histone deacetylase inhibitors (HDACi) in TNBC cell lines. We show that the pan-HDACi vorinostat and the class I HDACi romidepsin induce dose-dependent upregulation of SPCA2 transcript with concurrent downregulation of mesenchymal markers and tumor cell migration characteristic of epithelial phenotype. Silencing SPCA2 abolished the ability of HDACi to reverse epithelial to mesenchymal transition (EMT). Independent of ATPase activity, SPCA2 elevated resting Ca2+ levels to activate downstream components of non-canonical Wnt/Ca2+ signaling. HDACi treatment led to SPCA2-dependent phosphorylation of CAMKII and β-catenin, turning Wnt signaling off. We conclude that SPCA2 mediates the efficacy of HDACi in reversing EMT in TNBC by a novel mode of non-canonical Wnt/Ca2+ signaling. Our findings provide incentive for screening epigenetic modulators that exploit Ca2+ signaling pathways to reverse EMT in breast tumors.

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MiR-205 Dysregulations in Breast Cancer: The Complexity and Opportunities

Non-Coding RNA ◽

10.3390/ncrna5040053 ◽

2019 ◽

Vol 5 (4) ◽

pp. 53 ◽

Cited By ~ 9

Author(s):

Xiao ◽

Humphries ◽

Yang ◽

Wang

Keyword(s):

Breast Cancer ◽

Cell Proliferation ◽

Cancer Cell ◽

Target Gene ◽

Cancer Metastasis ◽

Epithelial Mesenchymal Transition ◽

Metastatic Breast ◽

Therapy Resistance ◽

Cancer Cell Proliferation ◽

Mesenchymal Transition

MicroRNAs (miRNAs) are endogenous non-coding small RNAs that downregulate target gene expression by imperfect base-pairing with the 3′ untranslated regions (3′UTRs) of target gene mRNAs. MiRNAs play important roles in regulating cancer cell proliferation, stemness maintenance, tumorigenesis, cancer metastasis, and cancer therapeutic resistance. While studies have shown that dysregulation of miRNA-205-5p (miR-205) expression is controversial in different types of human cancers, it is generally observed that miR-205-5p expression level is downregulated in breast cancer and that miR-205-5p exhibits a tumor suppressive function in breast cancer. This review focuses on the role of miR-205-5p dysregulation in different subtypes of breast cancer, with discussions on the effects of miR-205-5p on breast cancer cell proliferation, epithelial–mesenchymal transition (EMT), metastasis, stemness and therapy-resistance, as well as genetic and epigenetic mechanisms that regulate miR-205-5p expression in breast cancer. In addition, the potential diagnostic and therapeutic value of miR-205-5p in breast cancer is also discussed. A comprehensive list of validated miR-205-5p direct targets is presented. It is concluded that miR-205-5p is an important tumor suppressive miRNA capable of inhibiting the growth and metastasis of human breast cancer, especially triple negative breast cancer. MiR-205-5p might be both a potential diagnostic biomarker and a therapeutic target for metastatic breast cancer.

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