Genome-wide transcriptional regulation of estrogen receptor targets in fallopian tube cells and the role of selective estrogen receptor modulators

Abstract

BackgroundThe fallopian tube epithelium is one of the potential sources of high-grade serous ovarian cancer (HGSC). The use of estrogen only hormone replacement therapy increases ovarian cancer (OVCA) risk. Despite estrogen’s influence in OVCA, selective estrogen receptor modulators (SERMs) typically demonstrate only a 20 % response rate. This low response could be due to a variety of factors including the loss of estrogen receptor signaling or the role of estrogen in different potential cell types of origin. The response of fallopian tube epithelium to SERMs is not known, and would be useful when determining therapeutic options for tumors arising from this cell type, such as HGSC.ResultsUsing normal murine derived oviductal epithelial cells (mouse equivalent to the fallopian tube) estrogen receptor expression was confirmed and interaction with its ligand, estradiol, triggered mRNA and protein induction of progesterone receptor (PR). The SERMs 4-hydroxytamoxifen, raloxifene and desmethylarzoxifene, functioned as estrogen receptor antagonists in oviductal cells. Cellular proliferation and migration assays suggested that estradiol does not significantly impact cellular migration and increased proliferation. Further, using RNAseq, the oviduct specific transcriptional genes targets of ER when stimulated by estradiol and 4-hydroxytamoxifen signaling were determined and validated. The RNA-seq revealed enrichment in proliferation, anti-apoptosis, calcium signaling and steroid signaling processes. Finally, the ER and PR receptor status of a panel of HGSC cell lines was investigated including Kuramochi, OVSAHO, OVKATE, OVCAR3, and OVCAR4. OVSAHO demonstrated receptor expression and response, which highlights the need for additional models of ovarian cancer that are estrogen responsive.ConclusionsOverall, the fallopian tube has specific gene targets of estrogen receptor and demonstrates a tissue specific response to SERMs consistent with antagonistic action.Electronic supplementary materialThe online version of this article (doi:10.1186/s13048-016-0213-3) contains supplementary material, which is available to authorized users.

Activin A stimulates migration of the fallopian tube epithelium, an origin of high-grade serous ovarian cancer, through non-canonical signaling

“…The ovary produces a large number of hormones and growth factors that may stimulate migration of tumorigenic FTE cells to the ovaries. Estradiol is a major ovarian hormone, but it had no effect on migration of MOE cells [39]. In addition, steroids circulate systemically, making it unlikely that they stimulate the local migratory step from the fallopian tube to the ovary.…”

“…The next day the media was replaced with serum free MEM. Twenty-four hours later, media with appropriate treatments were added to each well and cell lysates were collected at indicated times in RIPA buffer containing protease and phosphatase inhibitors [39]. Protein concentrations were determined with a BCA assay (23227, Thermo Scientific, Waltham, MA), and 25 µg of protein was separated in a 10% SDS-PAGE gel by applying constant voltage (100 V) for 120 minutes.…”

Metabolism of Estrogens: Turnover Differs between Platinum-Sensitive and -Resistant High-Grade Serous Ovarian Cancer Cells

“…Preclinical studies have shown that estrogens can promote the proliferation of ovarian cancer cells lines and fuel tumor growth in mouse xenograft models [14], which is partly blocked by antiestrogens. Therefore, the use of endocrine disrupting agents in HGSOC could be promising [15]. Indeed, treatment of women with recurrent HGSOC using the antiestrogen tamoxifen or the aromatase inhibitor letrozole resulted in response rates between 10% and 15% and disease stabilization rates of 30% to 40% [16].…”

Single-cell RNA-sequencing reveals transcriptional dynamics of estrogen-induced dysplasia in the ovarian surface epithelium

“…Recent use of unbiased genomic and proteomics approaches demonstrate that both OSE and FTE are capable of giving rise to epithelial ovarian cancer [ 5 , 6 ]. Since our lab showed that prolonged E2 exposure impacts both cell types and genome-wide transcriptional regulation of estrogen receptor targets in mouse FTE was recently investigated [ 7 ], we present the transcription dynamics of estrogen-induced dysplasia in primary cultures of mouse OSE to further advance our understanding of how estrogen can accelerate transformation from either cells of origin.…”