Similar Datasets
Project description:Recurrence of metastatic breast cancer stemming from acquired endocrine and chemotherapy resistance remains a health burden for women with luminal (ER+) breast cancer. Disseminated ER+ tumor cells can remain viable but quiescent for years to decades. Contributing factors to metastatic spread include the maintenance and expansion of breast cancer stem cells (CSCs). Breast CSCs frequently exist as a minority population in therapy resistant tumors. In this study, we show that cytoplasmic complexes composed of steroid receptor (SR) co-activators, PELP1 and SRC-3, modulate breast CSC expansion through upregulation of the HIF-activated metabolic target genes PFKFB3 and PFKFB4. Seahorse metabolic assays demonstrated that cytoplasmic PELP1 influences cellular metabolism by increasing both glycolysis and mitochondrial respiration. PELP1 interacts with PFKFB3 and PFKFB4 proteins, and inhibition of PFKFB3 and PFKFB4 kinase activity blocks PELP1-induced tumorspheres and protein-protein interactions with SRC-3. PFKFB4 knockdown inhibited in vivo emergence of circulating tumor cell (CTC) populations in mammary intraductal (MIND) models. Application of PFKFB inhibitors in combination with ER targeted therapies blocked tumorsphere formation in multiple models of advanced breast cancer including tamoxifen (TamR) and paclitaxel (TaxR) resistant models, murine tumor cells, and ER+ patient-derived organoids (PDxO). Together, our data suggest that PELP1, SRC-3, and PFKFBs cooperate to drive ER+ tumor cell populations that include CSCs and CTCs. Identifying non-ER pharmacological targets offers a useful approach to blocking metastatic escape from standard of care ER/estrogen (E2)-targeted strategies to overcome endocrine and chemotherapy resistance.
| S-EPMC8238912 | biostudies-literature
Project description:Trascriptome analysis of mcf7 cell lines were performed
2020-10-09 | GSE159263 | GEO
Project description:PELP1/SRC-3-dependent regulation of metabolic kinases drives therapy resistant ER+ breast cancer [3D]
| PRJNA668175 | ENA
Project description:Breast cancer metastasis is a major clinical problem. The molecular basis of breast cancer progression to metastasis remains poorly understood. PELP1 is an estrogen receptor (ER) coregulator that has been implicated as a proto-oncogene whose expression is deregulated in metastatic breast tumors and whose expression is retained in ER-negative tumors. We examined the mechanism and significance of PELP1-mediated signaling in ER-negative breast cancer progression using two ER-negative model cells (MDA-MB-231 and 4T1 cells) that stably express PELP1-shRNA. These model cells had reduced PELP1 expression (75% of endogenous levels) and exhibited less propensity to proliferate in growth assays in vitro. PELP1 downregulation substantially affected migration of ER-negative cells in Boyden chamber and invasion assays. Using mechanistic studies, we found that PELP1 modulated expression of several genes involved in the epithelial mesenchymal transition (EMT), including MMPs, SNAIL, TWIST, and ZEB. In addition, PELP1 knockdown reduced the in vivo metastatic potential of ER-negative breast cancer cells and significantly reduced lung metastatic nodules in a xenograft assay. These results implicate PELP1 as having a role in ER-negative breast cancer metastasis, reveal novel mechanism of coregulator regulation of metastasis via promoting cell motility/EMT by modulating expression of genes, and suggest PELP1 may be a potential therapeutic target for metastatic ER-negative breast cancer.
| S-EPMC3262052 | biostudies-literature
Project description:In this study, we examined the mechanisms by which SETDB1 regulate the cell viability of estrogen receptor (ER) positive breast cancer cells. MCF7 cells were stably transfected with non-targeted shRNA or SETDB1 shRNA via lentiviral transduction. Total RNA was isolated and utilized for RNA-seq analysis. Our results demonstrated that SETDB1 regulates the expression of subsets of genes involved in ER-and Akt-signaling.
2022-04-13 | GSE187398 | GEO
Project description:The Proline-, glutamic acid- and leucine-rich protein 1 (PELP1) is an estrogen receptor (ER) coactivator and a proto-oncogene known to be deregulated in endocrine cancers. In breast cancer, PELP1 overexpression has been associated with endocrine therapy resistance. Although PELP1 is known to be regulated by estrogens in vitro, its association with estrogen levels within the tissue of breast cancer patients has not previously been assessed. Here, we determined PELP1 mRNA expression levels in paired samples of normal and malignant breast tissue obtained from 32 postmenopausal and 11 premenopausal women. In the total sample set, PELP1 levels were higher in tumors compared to normal breast tissue (P = 0.041). Among postmenopausal women, PELP1 tumor levels correlated positively with estrone (E1) and estradiol (E2) levels in both normal tissue (r = 0.543, P = 0.003 and r = 0.601, P = 0.001, respectively) and plasma (r = 0.392, P = 0.053 and r = 0.403, P = 0.046, respectively). Analyzing all ER+ tumors (n = 26), PELP1 correlated positively with E1 and E2 in tumor tissue (r = 0.562, P = 0.003 and r = 0.411, P = 0.037, respectively) and normal tissue (r = 0.461, P = 0.018 and r = 0.427, P = 0.030, respectively) in addition to plasma E1, E2 and estrone sulphate (E1S) concentrations (r = 0.576, P = 0.003, r = 0.456, P = 0.025 and r = 0.406, P = 0.049, respectively). Finally, PELP1 correlated positively with ER mRNA (ESR1) (r = 0.553, P = 0.026) in ER+ tumors, whereas a negative association between PELP1 and ESR1 (r = -0.733, P = 0.010) was observed in ER- breast tumors. Taken together, tumor PELP1 mRNA expression is associated with estrogen levels in breast cancer, suggesting a potentially important role of PELP1 in ER+ breast cancer growth in vivo.
| S-EPMC4527840 | biostudies-literature
Project description:To investigate the function of VGLL1 in breast cancer and its role in the resistance to endocrine therapies we generated stable MCF7 cells overexpressing VGLL1 using CRISPR/Cas9 Synergistic Activation Mediator (SAM) method (MCF7 ActCas9-VGLL1 cells). MCF7 ActCas9-VGLL1 cells were also cultured in the presence of fulvestrant 100nmM or 1µM to develop fulvestrant resistant cells (MCF7 ActCas9-VGLL1-FULVR) and RNA-seq was performed in the different cell lines.
2023-12-05 | GSE216528 | GEO
Project description:To elucidate the molecular mechanisms of tamoxifen resistance in breast cancer, we performed gene array analysis and identified 366 genes with altered expression in four unique tamoxifen resistant (TamR) cell lines vs the parental tamoxifen sensitive MCF7/S0.5 cell line. Most of these genes were funcationally linked to cell proliferation, death and control gene expression, and include FYN, PRKCA, ITPR1, DPYD, DACH1, LYN, GBP1 and PRLR. Treatment with FYN specific small interfering RNA or a SRC family kinase inhibitor reduced cell growth of TamR cell lines while exerting no significant effect on MCF7/S0.5 cells. Moreover, overexpression of FYN in parental tamoxifen-sensitive MCF7/S0.5 cells resulted in reduced sensitivity to tamoxifen, demonstrating growth and survival promoting function of FYN in MCF7 cells. FYN knockdown in TamR cells led to reduced phosphorylation of 14-3-3 and CDc 25A, suggesting that FYN, by activation of of important cell cycle-associated proteins, may overcome the anti-proliferative effects of tamoxifen. Evaluation of the subcellular localization of FYN in primary breast tumors from two cohorts of endocrine-treated ER+ breast cancer patients, one with advanced disease (N = 47) and the other with early disease (N = 76), showed that in the former, plasma membrane-associated FYN expression strongly correlated with longer progression-free survival (P<0.0002). Similarly, in early breast cancer patients, membrane-associated expression of FYN in the primary breast tumor was significantly associated with increased metastasis-free (P<0.04) and overall (P<0.004) survival independent of tumor size, grade or lymph node status. Our results indicate that FYN has an important role in tamoxifen resistance, and its subcellular localization in breast tumor cells may be an important novel biomarker of response to endocrine therapy in breast cancer.
2016-04-10 | GSE67916 | GEO
Project description:The transcriptional activity of the TEAD4 trascription factor requires co-activators. In this study we found that the expression of the TEAD coactivator VGLL1 is repressed in estrogen receptor positive breast cancer but upon resistance to endocrine threapies VGLL1 is expressed to high levels. To elucidate the importance of the coactivator VGLL1 in breast cancer cells resistant to endocrine therapies and to identify the VGLL1 target genes, we performed ChIP-seq for VGLL1 in MCF7 breast cancer cells resistant to fulvestrant (FULVR) and ChiP-seq for TEAD4 in FULVR cells and the isogenic MCF7 cells.
2023-12-05 | GSE216525 | GEO
Project description:To investigate the molecular mechanisms of resistance to ER downregulator and CDK4/6 inhibitors in ER+ breast cancer, we generated two cell lines, MCF7 and T47D, resistant to fulvestrant and abemaciclib after 6-8 months of exposure to increasing doses of the drug combination We performed gene expression profiling analysis using data obtained from RNA-seq of parental MCF7 or T47D and the respective fulvestrant and abemaciclib resistant cells
2023-06-05 | GSE227102 | GEO