Clinical and genomic crosstalk between glucocorticoid receptor and estrogen receptor α in endometrial cancer [ATAC-seq]
Ontology highlight
ABSTRACT: Steroid hormone receptors are simultaneously active in many tissues and capable of altering each other's function. Estrogen receptor ɑ (ER) and glucocorticoid receptor (GR) are expressed in the uterus and their ligands have opposing effects on uterine growth. In endometrial tumors expressing high levels of ER, we surprisingly found that expression of GR is associated with poor prognosis. Dexamethasone reduced normal uterine growth in vivo; however, this growth inhibition was abolished in estrogen-induced endometrial hyperplasia. We observed low genomic binding site overlap when ER and GR are induced with their respective ligands; however, upon simultaneous induction they co-occupy more sites. GR binding is significantly altered by estradiol with GR recruited to ER bound loci that become more accessible upon estradiol induction. Gene expression responses to co-treatment were more similar to estradiol, but with novel regulated genes. Our results suggest phenotypic and molecular interplay between ER and GR in endometrial cancer.
Project description:Steroid hormone receptors are simultaneously active in many tissues and capable of altering each other's function. Estrogen receptor ɑ (ER) and glucocorticoid receptor (GR) are expressed in the uterus and their ligands have opposing effects on uterine growth. In endometrial tumors expressing high levels of ER, we surprisingly found that expression of GR is associated with poor prognosis. Dexamethasone reduced normal uterine growth in vivo; however, this growth inhibition was abolished in estrogen-induced endometrial hyperplasia. We observed low genomic binding site overlap when ER and GR are induced with their respective ligands; however, upon simultaneous induction they co-occupy more sites. GR binding is significantly altered by estradiol with GR recruited to ER bound loci that become more accessible upon estradiol induction. Gene expression responses to co-treatment were more similar to estradiol, but with novel regulated genes. Our results suggest phenotypic and molecular interplay between ER and GR in endometrial cancer.
Project description:Steroid hormone receptors are simultaneously active in many tissues and capable of altering each other's function. Estrogen receptor ɑ (ER) and glucocorticoid receptor (GR) are expressed in the uterus and their ligands have opposing effects on uterine growth. In endometrial tumors expressing high levels of ER, we surprisingly found that expression of GR is associated with poor prognosis. Dexamethasone reduced normal uterine growth in vivo; however, this growth inhibition was abolished in estrogen-induced endometrial hyperplasia. We observed low genomic binding site overlap when ER and GR are induced with their respective ligands; however, upon simultaneous induction they co-occupy more sites. GR binding is significantly altered by estradiol with GR recruited to ER bound loci that become more accessible upon estradiol induction. Gene expression responses to co-treatment were more similar to estradiol, but with novel regulated genes. Our results suggest phenotypic and molecular interplay between ER and GR in endometrial cancer.
Project description:Treatment with the breast cancer drug tamoxifen confers a risk of developing uterine tumors or other endometrial pathologies. Tamoxifen is a selective estrogen receptor modulator, which demonstrates tissue-specific activity although the mechanisms remain poorly understood. Both estradiol and tamoxifen act as estrogen agonists on the human uterus, and therefore have the potential to promote carcinogenicity. Estradiol and tamoxifen elicit cellular responses via the estrogen receptors (ER), which are involved in multiple signalling pathways. The effects at the molecular level are further influenced by the differential recruitment of co-factors and the presence of specific promoter motifs in target genes. In this study, ER positive (+) Ishikawa cells are used as a model to investigate the overall effect of treatment with either 17b-estradiol or 4-hydroxytamoxifen on the gene expression profiles. Keywords: Comparison of estradiol and tamoxifen on Ishikawa human uterine cells after 24h or 48h
Project description:Estrogen signaling through estrogen receptor alpha (ER) plays a major role in endometrial cancer risk and progression; however, the molecular mechanisms underlying ER’s regulatory role in endometrial cancer are poorly understood. In breast cancer cells, ER genomic binding is enabled by FOXA1 and GATA3, but the transcription factors that control ER genomic binding in endometrial cancer cells remain unknown. We previously identified ETV4 as a candidate factor controlling ER genomic binding in endometrial cancer cells and here we explore the functional importance of ETV4. Homozygous deletion of ETV4, using CRISPR/Cas9, led to greatly reduced ER binding at the majority of loci normally bound by ER. Consistent with the dramatic loss of ER binding, the gene expression response to estradiol was dampened for most genes. ETV4 contributes to estrogen signaling in two distinct ways; ETV4 loss impacts chromatin accessibility at some ER bound loci and impairs ER nuclear translocation. The diminished estrogen signaling upon ETV4 deletion led to decreased growth, particularly in 3D culture where hollow organoids were formed. Our results show that ETV4 plays a necessary role in estrogen signaling in endometrial cancer cells.
Project description:Estrogen signaling through estrogen receptor alpha (ER) plays a major role in endometrial cancer risk and progression; however, the molecular mechanisms underlying ER’s regulatory role in endometrial cancer are poorly understood. In breast cancer cells, ER genomic binding is enabled by FOXA1 and GATA3, but the transcription factors that control ER genomic binding in endometrial cancer cells remain unknown. We previously identified ETV4 as a candidate factor controlling ER genomic binding in endometrial cancer cells and here we explore the functional importance of ETV4. Homozygous deletion of ETV4, using CRISPR/Cas9, led to greatly reduced ER binding at the majority of loci normally bound by ER. Consistent with the dramatic loss of ER binding, the gene expression response to estradiol was dampened for most genes. ETV4 contributes to estrogen signaling in two distinct ways; ETV4 loss impacts chromatin accessibility at some ER bound loci and impairs ER nuclear translocation. The diminished estrogen signaling upon ETV4 deletion led to decreased growth, particularly in 3D culture where hollow organoids were formed. Our results show that ETV4 plays a necessary role in estrogen signaling in endometrial cancer cells.
Project description:Estrogen signaling through estrogen receptor alpha (ER) plays a major role in endometrial cancer risk and progression; however, the molecular mechanisms underlying ER’s regulatory role in endometrial cancer are poorly understood. In breast cancer cells, ER genomic binding is enabled by FOXA1 and GATA3, but the transcription factors that control ER genomic binding in endometrial cancer cells remain unknown. We previously identified ETV4 as a candidate factor controlling ER genomic binding in endometrial cancer cells and here we explore the functional importance of ETV4. Homozygous deletion of ETV4, using CRISPR/Cas9, led to greatly reduced ER binding at the majority of loci normally bound by ER. Consistent with the dramatic loss of ER binding, the gene expression response to estradiol was dampened for most genes. ETV4 contributes to estrogen signaling in two distinct ways; ETV4 loss impacts chromatin accessibility at some ER bound loci and impairs ER nuclear translocation. The diminished estrogen signaling upon ETV4 deletion led to decreased growth, particularly in 3D culture where hollow organoids were formed. Our results show that ETV4 plays a necessary role in estrogen signaling in endometrial cancer cells.
Project description:Analysis of the genome-wide response of the ER:PRL-HeLa cell line to treatment with estrogen receptor ligands estradiol, 4H-tamoxifen and bisphenol-A.
Project description:Analysis of the genome-wide response of the ER:PRL-HeLa cell line to treatment with estrogen receptor ligands estradiol, 4H-tamoxifen and bisphenol-A. Total RNA obtained from ER:PRL-HeLa cells treated for 4 hours with estradiol, 4H-tamoxifen or bisphenol -A is compared to vehicle treated controls
Project description:Most endometrial cancers are driven by excess estrogen signaling and express the hormone receptor estrogen receptor alpha (ER). Evaluation of the estrogen response in endometrial cancer cells has been limited by the availability of hormonally responsive in vitro models, with one cell line, Ishikawa, being used in most studies. Here, we describe a novel, adherent endometrioid endometrial cancer (EEC) cell line model, HCI-EC-23. We show that HCI-EC-23 retains ER expression and that ER functionally responds to 17b-estradiol (E2) induction over a range of passages. We also demonstrate that this cell line retains paradoxical activation of ER by tamoxifen, which is also observed in Ishikawa and is consistent with clinical data. The mutational landscape shows that HCI-EC-23 is mutated at many of the commonly altered genes in EEC, has relatively few copy-number alterations, and is microsatellite instable high (MSI-high). In vitro proliferation of HCI-EC-23 is modestly enhanced by E2 but is strongly reduced upon combination E2 and progesterone (P4) treatment. HCI-EC-23 exhibit strong E2 dependence for tumor growth in vivo and tumor size is reduced by combination E2 + P4 treatment. Molecular characterization of E2 induction in HCI-EC-23 revealed hundreds of estrogen-responsive genes that significantly overlapped with those regulated in Ishikawa. Analysis of ER genome binding identified similar patterns in HCI-EC-23 and Ishikawa, although ER exhibited more bound sites in Ishikawa. This study demonstrates that HCI-EC-23 is estrogen-responsive and can be used to study the hormonal aspects of endometrial cancer.
Project description:Most endometrial cancers are driven by excess estrogen signaling and express the hormone receptor estrogen receptor alpha (ER). Evaluation of the estrogen response in endometrial cancer cells has been limited by the availability of hormonally responsive in vitro models, with one cell line, Ishikawa, being used in most studies. Here, we describe a novel, adherent endometrioid endometrial cancer (EEC) cell line model, HCI-EC-23. We show that HCI-EC-23 retains ER expression and that ER functionally responds to 17b-estradiol (E2) induction over a range of passages. We also demonstrate that this cell line retains paradoxical activation of ER by tamoxifen, which is also observed in Ishikawa and is consistent with clinical data. The mutational landscape shows that HCI-EC-23 is mutated at many of the commonly altered genes in EEC, has relatively few copy-number alterations, and is microsatellite instable high (MSI-high). In vitro proliferation of HCI-EC-23 is modestly enhanced by E2 but is strongly reduced upon combination E2 and progesterone (P4) treatment. HCI-EC-23 exhibit strong E2 dependence for tumor growth in vivo and tumor size is reduced by combination E2 + P4 treatment. Molecular characterization of E2 induction in HCI-EC-23 revealed hundreds of estrogen-responsive genes that significantly overlapped with those regulated in Ishikawa. Analysis of ER genome binding identified similar patterns in HCI-EC-23 and Ishikawa, although ER exhibited more bound sites in Ishikawa. This study demonstrates that HCI-EC-23 is estrogen-responsive and can be used to study the hormonal aspects of endometrial cancer.