scholarly journals Estrogen Regulation of the Glucuronidation Enzyme UGT2B15 in Estrogen Receptor-Positive Breast Cancer Cells

Endocrinology ◽  
2006 ◽  
Vol 147 (8) ◽  
pp. 3843-3850 ◽  
Author(s):  
William R. Harrington ◽  
Surojeet Sengupta ◽  
Benita S. Katzenellenbogen
Keyword(s):  
Breast Cancer ◽  
Estrogen Receptor ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Steroid Hormone ◽  
Transcriptional Response ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Estrogen Regulation ◽  
Estradiol Stimulation

Estrogens and androgens influence many properties of breast cancer cells; hence, regulation of local estrogen and androgen levels by enzymes involved in steroid hormone biosynthesis and metabolism would impact signaling by these hormones in breast cancer cells. In this study, we show that the UDP-glucuronosyltransferase (UGT) enzyme UGT2B15, a member of the UGT family of phase II enzymes involved in the glucuronidation of steroids and xenobiotics, is a novel, estrogen-regulated gene in estrogen receptor (ER)-positive human breast cancer cells (MCF-7, BT474, T47D, and ZR-75). UGT2B15 is the only UGT2B enzyme up-regulated by estrogen, and marked estradiol stimulation of UGT2B15 mRNA levels is observed, in a time- and dose-dependent manner. UGT2B15 stimulation by estradiol is blocked by the antiestrogen ICI182,780, but not by the translational inhibitor cycloheximide, indicating that UGT2B15 is likely a primary transcriptional response mediated through the ER. UGT2B15 up-regulation is also evoked by other estrogens (propylpyrazoletriol, genistein) and by the androgen 5α-dihydrotestosterone working through the ER, but not by other steroid hormone receptor ligands. Western blot and immunocytochemical analyses with several UGT2B-specific antibodies we have designed and steroid glucuronidation assays indicate a large increase in both cellular UGT2B15 protein and enzyme activity after estrogen treatment. Due to the important role of UGT enzymes in forming conjugates between steroids and glucuronic acid, thereby inactivating them and targeting them for removal, the estrogen-induced up-regulation of UGT2B15 might have a significant moderating effect on estrogen and androgen concentrations, thereby reducing their signaling in breast cancer cells.

scholarly journals Poly-ADP-Ribosylation of Estrogen Receptor-Alpha by PARP1 Mediates Antiestrogen Resistance in Human Breast Cancer Cells

Cancers ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 43 ◽  
Author(s):  
Nicholas Pulliam ◽  
Jessica Tang ◽  
Weini Wang ◽  
Fang Fang ◽  
Riddhi Sood ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Oxidative Stress ◽  
Estrogen Receptor ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Target Genes ◽  
Tamoxifen Resistance ◽  
Tamoxifen Treatment ◽  
Dependent Manner ◽  
Tamoxifen Resistant

Therapeutic targeting of estrogen receptor-α (ERα) by the anti-estrogen tamoxifen is standard of care for premenopausal breast cancer patients and remains a key component of treatment strategies for postmenopausal patients. While tamoxifen significantly increases overall survival, tamoxifen resistance remains a major limitation despite continued expression of ERα in resistant tumors. Previous reports have described increased oxidative stress in tamoxifen resistant versus sensitive breast cancer and a role for PARP1 in mediating oxidative damage repair. We hypothesized that PARP1 activity mediated tamoxifen resistance in ERα-positive breast cancer and that combining the antiestrogen tamoxifen with a PARP1 inhibitor (PARPi) would sensitize tamoxifen resistant cells to tamoxifen therapy. In tamoxifen-resistant vs. -sensitive breast cancer cells, oxidative stress and PARP1 overexpression were increased. Furthermore, differential PARylation of ERα was observed in tamoxifen-resistant versus -sensitive cells, and ERα PARylation was increased by tamoxifen treatment. Loss of ERα PARylation following treatment with a PARP inhibitor (talazoparib) augmented tamoxifen sensitivity and decreased localization of both ERα and PARP1 to ERα-target genes. Co-administration of talazoparib plus tamoxifen increased DNA damage accumulation and decreased cell survival in a dose-dependent manner. The ability of PARPi to overcome tamoxifen resistance was dependent on ERα, as lack of ERα-mediated estrogen signaling expression and showed no response to tamoxifen-PARPi treatment. These results correlate ERα PARylation with tamoxifen resistance and indicate a novel mechanism-based approach to overcome tamoxifen resistance in ER+ breast cancer.

scholarly journals SAT-124 Optimization of Experimental Conditions for Mimicking Hypoxia in Cultured Breast Cancer Cells by Using Cobalt(II) Chloride (CoCl2)

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Karin Chen ◽  
Leo Satlof ◽  
Udithi Kothapalli ◽  
Noah Ziluck ◽  
Maribel Lema ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Cell Apoptosis ◽  
Breast Cancer Cells ◽  
Nuclear Translocation ◽  
Breast Cancer Cell Lines ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Experimental Conditions

Abstract Hypoxia is a common phenomenon in solid tumor development caused by a decrease in either oxygen concentration or oxygen pressure as a result of rapid tumor cell growth. Hypoxia is characterized by stabilization of the alpha subunit of the hypoxia-inducible factor (HIF-1α) and its nuclear translocation and heterodimerization with HIF-1β. Activation of this signaling pathway involves multiple downstream effectors including carbonic anhydrase 9 (CA9, s. CAIX). A reliable method to mimic hypoxia utilizes cobalt(II) chloride (CoCl2), which directly induces the expression of HIF-1α. The aim of this study was to optimize the experimental conditions for CoCl2 treatment of breast cancer cells in vitro using three human breast cancer cell lines (MDA-MB-231, T-47D, and MCF-7 cells). We performed time- and concentration-response experiments, using various concentrations of CoCl2 (50, 100, 200, and 300 μM) for 24 and 48 hours, and measured the expression of HIF-1α and CA9 by qRT-PCR and Western blot analyses. Results demonstrated that CoCl2 downregulated HIF-1α mRNA levels but upregulated CA9 mRNA levels in a concentration- and time-dependent manner. Concomitantly, CoCl2 treatment resulted in a significant induction of HIF-1α protein levels. We further investigated the effect of the CoCl2 concentrations listed above on cell apoptosis using an in situ apoptosis detection kit. The results demonstrated that concentrations of CoCl2 up to 100 μM had no significant effect on cell apoptosis.

scholarly journals Coactivator Function Defines the Active Estrogen Receptor Alpha Cistrome

2009 ◽  
Vol 29 (12) ◽  
pp. 3413-3423 ◽  
Author(s):  
Mathieu Lupien ◽  
Jérôme Eeckhoute ◽  
Clifford A. Meyer ◽  
Susan A. Krum ◽  
Daniel R. Rhodes ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Estrogen Receptor ◽  
Cancer Cells ◽  
Rna Polymerase Ii ◽  
Breast Cancer Cells ◽  
Estrogen Receptor Alpha ◽  
Transcriptional Response ◽  
Transcriptional Networks ◽  
Receptor Alpha ◽  
Genomic Regions

ABSTRACT Proper activation of transcriptional networks in complex organisms is central to the response to stimuli. We demonstrate that the selective activation of a subset of the estrogen receptor alpha (ERα) cistrome in MCF7 breast cancer cells provides specificity to the estradiol (E2) response. ERα-specific enhancers that are subject to E2-induced coactivator-associated arginine methyltransferase 1 (CARM1) action are critical to E2-stimulated gene expression. This is true for both FoxA1-dependent and independent enhancers. In contrast, a subset of E2-suppressed genes are controlled by FoxA1-independent ERα binding sites. Nonetheless, these are sites of E2-induced CARM1 activity. In addition, the MCF7 RNA polymerase II cistrome reveals preferential occupancy of E2-regulated promoters prior to stimulation. Interestingly, E2-suppressed genes tend to lie in otherwise silent genomic regions. Together, our results suggest that the transcriptional response to E2 in breast cancer cells is dependent on the interplay between polymerase II pre-occupied promoters and the subset of the ERα cistrome associated with coactivation.

scholarly journals Biochanin A Promotes Proliferation that Involves a Feedback Loop of MicroRNA-375 and Estrogen Receptor Alpha in Breast Cancer Cells

2015 ◽  
Vol 35 (2) ◽  
pp. 639-646 ◽  
Author(s):  
Jian Chen ◽  
Bo Ge ◽  
Yong Wang ◽  
Yu Ye ◽  
Sien Zeng ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Proliferation ◽  
Estrogen Receptor ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Feedback Loop ◽  
Biochanin A ◽  
Mrna Levels ◽  
Mcf 7

Background: Biochanin A and formononetin are O-methylated isoflavones that are isolated from the root of Astragalus membranaceus, and have antitumorigenic effects. Our previous studies found that formononetin triggered growth-inhibitory and apoptotic activities in MCF-7 breast cancer cells. We performed in vivo and in vitro studies to further investigate the potential effect of biochanin A in promoting cell proliferation in estrogen receptor (ER)-positive cells, and to elucidate underlying mechanisms. Methods: ERα-positive breast cancer cells (T47D, MCF-7) were treated with biochanin A. The MTT assay and flow cytometry were used to assess cell proliferation and apoptosis. mRNA levels of ERα, Bcl-2, and miR-375 were quantified using real-time polymerase chain reaction. Compared with the control, low biochanin A concentrations (2-6 μM) stimulated ERα-positive cell proliferation (T47D, MCF-7). The more sensitive T47D cells were used to study the relevant signaling pathway. Results: After treatment with biochanin A, ERα, miR-375, and Bcl-2 expression was significantly upregulated. Additionally, in the in vivo studies, uterine weight in ovariectomized mice treated with biochanin A increased significantly. Conclusion: This study demonstrated that biochanin A promoted ERα-positive cell proliferation through miR-375 activation and this mechanism is possibly involving in a miR-375 and ERα feedback loop.

scholarly journals KISS1R Induces Invasiveness of Estrogen Receptor-Negative Human Mammary Epithelial and Breast Cancer Cells

Endocrinology ◽  
2013 ◽  
Vol 154 (6) ◽  
pp. 1999-2014 ◽  
Author(s):  
Donna Cvetković ◽  
Magdalena Dragan ◽  
Sean J. Leith ◽  
Zuhaib M. Mir ◽  
Hon S. Leong ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Estrogen Receptor ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Mammary Epithelial ◽  
Metastasis Suppressor ◽  
Dependent Manner ◽  
Egfr Transactivation ◽  
Exogenous Expression ◽  
Mcf10a Cells

Abstract Kisspeptins (KPs), peptide products of the KISS1 metastasis-suppressor gene, are endogenous ligands for a G protein-coupled receptor (KISS1R). KISS1 acts as a metastasis suppressor in numerous human cancers. However, recent studies have demonstrated that an increase in KISS1 and KISS1R expression in patient breast tumors correlates with higher tumor grade and metastatic potential. We have shown that KP-10 stimulates invasion of estrogen receptor α (ERα)-negative MDA-MB-231 breast cancer cells via transactivation of the epidermal growth factor receptor (EGFR). Here, we report that either KP-10 treatment of ERα-negative nonmalignant mammary epithelial MCF10A cells or expression of KISS1R in MCF10A cells induced a mesenchymal phenotype and stimulated invasiveness. Similarly, exogenous expression of KISS1R in ERα-negative SKBR3 breast cancer cells was sufficient to trigger invasion and induced extravasation in vivo. In contrast, KP-10 failed to transactivate EGFR or stimulate invasiveness in the ERα-positive MCF7 and T47D breast cancer cells. This suggested that ERα negatively regulates KISS1R-dependent breast cancer cell migration, invasion, and EGFR transactivation. In support of this, we found that these KP-10-induced effects were ablated upon exogenous expression of ERα in the MDA-MB-231 cells, by down-regulating KISS1R expression. Lastly, we have identified IQGAP1, an actin cytoskeletal binding protein as a novel binding partner of KISS1R, and have shown that KISS1R regulates EGFR transactivation in breast cancer cells in an IQGAP1-dependent manner. Overall, our data strongly suggest that the ERα status of mammary cells dictates whether KISS1R may be a novel clinical target for treating breast cancer metastasis.

scholarly journals Overexpression of the urokinase receptor splice variant uPAR-del4/5 in breast cancer cells affects cell adhesion and invasion in a dose-dependent manner and modulates transcription of tumor-associated genes

2012 ◽  
Vol 393 (12) ◽  
pp. 1449-1455 ◽  
Author(s):  
Bettina Grismayer ◽  
Sumito Sato ◽  
Charlotte Kopitz ◽  
Christian Ries ◽  
Susanne Soelch ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Adhesion ◽  
Cancer Cells ◽  
Splice Variant ◽  
Breast Cancer Cells ◽  
Urokinase Receptor ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Dose Dependent ◽  
Adhesion And Invasion

Abstract mRNA levels of the urokinase receptor splice variant uPAR-del4/5 are associated with prognosis in breast cancer. Its overexpression in cancer cells affects tumor biologically relevant processes. In the present study, individual breast cancer cell clones displaying low vs. high uPAR-del4/5 expression were analyzed demonstrating that uPAR-del4/5 leads to reduced cell adhesion and invasion in a dose-dependent manner. Additionally, matrix metalloproteinase-9 (MMP-9) was found to be strongly upregulated in uPAR-del4/5 overexpressing compared to vector control cells. uPAR-del4/5 may thus play an important role in the regulation of the extracellular proteolytic network and, by this, influence the metastatic potential of breast cancer cells.

Momordica charantia Seed and Aryl Extracts Potentiate Growth Inhibition and Apoptosis by Dual Blocking of PI3K/AKT and MAPK Pathways as a Downstream Target of EGFR Signaling in Breast Cancer Cells

2020 ◽  
Vol 16 (5) ◽  
pp. 726-733
Author(s):  
Guzide Satir Basaran ◽  
Hatice Bekci ◽  
Ayse Baldemir ◽  
Selen Ilgun ◽  
Ahmet Cumaoglu
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Cell Lines ◽  
Breast Cancer Cells ◽  
Molecular Mechanisms ◽  
Therapeutic Potential ◽  
Momordica Charantia ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Seed Extracts

Background and Objective: Herbal extracts and plant compounds are increasingly becoming of interest for their therapeutic potential in various cancer types. Momordica charantia is well known for its anti-diabetic, anti-inflammatory, and anti-cancer properties. Methods: In the present study, we investigated the antiproliferative and pro-apoptotic effects of Momordica charantia seed and aryl extracts on breast cancer cells and explored the underlying molecular mechanisms. Results: Our results showed that both extract significantly inhibited the growth of MCF-7 and MDA MB-231 cells in a concentration-dependent manner, and induced apoptosis by upregulation of caspase 9 and caspase 3 mRNA levels. In addition, in different incubation time, both extract evidently inhibited EGF and induced EGFR phosphorylation/activation in both cell lines. Moreover, Momordica charantia aryl and seed extracts inhibited phosphorylation/activation of PI3K/AKT and MAPK (ERK and P38) pathways in both cell lines. Conclusion: The current study clearly demonstrates that the Momordica charantia aryl and seed extracts have the potential to exert its cytotoxic effect on breast cancer cells by a mechanism involving inhibition of EGFR and EGRF related pathways with the induction of apoptosis. The overall finding demonstrates that this plant, especially seed extract, could be a potential source of new anticancer compounds for possible drug development against cancer.

scholarly journals NLRC4, ASC and Caspase-1 Are Inflammasome Components That Are Mediated by P2Y2R Activation in Breast Cancer Cells

2020 ◽  
Vol 21 (9) ◽  
pp. 3337 ◽  
Author(s):  
Hana Jin ◽  
Hye Jung Kim
Keyword(s):  
Breast Cancer ◽  
Tumor Progression ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Inflammasome Activation ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Protein Levels ◽  
Caspase 1 ◽  
Tnf Α

The inflammasomes are reported to be associated with tumor progression. In our previous study, we determined that extracellular ATP enhances invasion and tumor growth by inducing inflammasome activation in a P2Y purinergic receptor 2 (P2Y2R)-dependent manner. However, it is not clear which inflammasome among the diverse complexes is associated with P2Y2R activation in breast cancer. Thus, in this study, we determined which inflammasome components are regulated by P2Y2R activation and are involved in tumor progression in breast cancer cells and radiotherapy-resistant (RT-R)-breast cancer cells. First, we found that NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3); NLR family caspase activation and recruitment domain (CARD) containing 4 (NLRC4); apoptosis-associated speck-like protein containing a CARD complex (ASC); and caspase-1 mRNA levels were upregulated in RT-R-MDA-MB-231 cells compared to MDA-MB-231 cells, whereas tumor necrosis factor-α (TNF-α) or ATP treatment induced NLRC4, ASC, and caspase-1 but not NLRP3 protein levels. Moreover, TNF-α or ATP increased protein levels of NLRC4, ASC, and caspase-1 in a P2Y2R-dependent manner in MDA-MB-231 and RT-R-MDA-MB-231 cells. In addition, P2Y2R activation by ATP induced the secretion of IL-1β and VEGF-A, as well as invasion, in MDA-MB-231 and RT-R-MDA-MB-231 cells, which was inhibited by NLRC4, ASC, and caspase-1 small interfering RNA (siRNA). Taken together, this report suggests that P2Y2R activation by ATP induces tumor invasion and angiogenesis through inflammasome activation, specifically by regulating the inflammasome components NLRC4, ASC, and caspase-1.

scholarly journals Investigation of the effect of estradiol and subculturing on the receptor expression within hormone-dependent breast cancer cells

2019 ◽  
Author(s):  
Avijit Mallick ◽  
Sabbir Ahmed
Keyword(s):  
Breast Cancer ◽  
Cell Proliferation ◽  
Estrogen Receptor ◽  
Cancer Cells ◽  
Cell Line ◽  
Cancer Cell ◽  
Breast Cancer Cell ◽  
Breast Cancer Cells ◽  
Receptor Expression ◽  
Dependent Manner

SUMMARYIt is now known that a very crucial role in breast cancer development, prognosis and occurrence is played by the estrogen receptor (ER). The steroid hormone estradiol (E2) acts via two nuclear receptors, estrogen receptor-α (ERα) and estrogen receptor-β (ERβ). E2 was shown previously to increase breast cancer cell proliferation in a dose-dependent manner and also induce apoptosis in long term estrogen deprived breast cancer cells. Studies have also shown that the degree of subculturing affects cell line property including gene expression. The aim of this study was to investigate the effect of E2 concentration on cell proliferation, morphology and ER expression and to investigate the effect of subculturing on the expression of ER. Our results have shown that an increase in E2 concentration was found to increase MCF-7 cell proliferation, but extreme concentrations caused significantly low cell proliferation and induced apoptosis. Moreover, ERα expression was significantly upregulated with an increase in E2 concentration, whereas ERβ2 expression was found to be unchanged at low E2 concentration and significantly upregulated at higher E2 concentration. ERα expression at passage 3 ([E2]=1nM) was significantly downregulated compared to the cells at passage 0, in addition to the significant downregulation of the same at E2 concentrations of 1nM and 10µM compared to the untreated control sample. Overall, our data suggests that high concentration of E2 can reduce proliferation and induce apoptosis in the breast cancer cells. Increased E2 exposure and subculturing also appear to change the ERα expression significantly in the breast cancer cell line.

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