Novel endocrine therapeutic strategy in endometrial carcinoma targeting estrogen-related receptor α by XCT790 and siRNA

Abstract

PurposeTo explore the targeted therapy of estrogen-related receptor α (ERRα) in endometrial cancer (EC) cells and its potential mechanisms.MethodsThe mRNA and protein expression levels of ERRα and estrogen receptor α (ERα) were detected by qPCR and Western blotting in RL-952, AN3-CA, HEC-1A, and HEC-1B EC cell lines. After treatment with the ERRα-specific antagonist XCT790 or infection with lentivirus-mediated small interfering RNA (siRNA) targeting the ERRα (siRNA-ERRα), cell proliferation and apoptosis were evaluated by MTS assay and flow cytometry. After treatment with siRNA-ERRα, the expression profiles of transcription factors (TFs) were analyzed by protein/DNA arrays in EC cells.ResultsThe relative mRNA levels of ERRa in RL-952 (1±0.0831) and AN3-CA (1.162±0.0325) were significantly higher than those in HEC-1A (0.3081±0.0339) and HEC-1B (0.1119±0.0091) (P<0.05), and similar results were observed for ERRα protein levels. A higher ratio of ERa/ERRa was observed in ERα-positive RL-952 (10-fold) and ANC-3A (8.5-fold) cells, whereas a lower ratio was observed in ERα-negative HEC-1A (3.75-fold) and HEC-1B cells (0-fold). Both – exogenous XCT790 and endogenous siRNA-ERRα – can decrease the expression of ERRα, thereby inhibiting proliferation but promoting apoptosis in both ERα-positive and -negative EC cells. The XCT790 presented higher proliferation-inhibition and apoptosis rates in the ERα-positive than ERα-negative cells, whereas the siRNA-ERRα exhibited higher proliferation-inhibition and apoptosis rates in the ERα-negative than in ERα-positive cells. In total, 3 upregulated and 17 downregulated TFs were screened out by knocked-down expression of ERRα in all EC cells. Among them, the upregulated TFs organic cation transporter 3/4(Oct3/4), hepatic nuclear factor 4 (HNF4), HNF4 and chicken ovalbumin upstream TF (COUP-TF) as well as downregulated transcription factor EB (TFEB) were found to be statistically significant (P<0.05).ConclusionTargeting ERRα provides a promising novel endocrine therapeutic strategy.

PGC-1α and ERRα in patients with endometrial cancer: a translational study for predicting myometrial invasion

“…The endometrial cancer cell lines RL-952, ECC-1, HEC-1A and HEC-1B were purchased from the American Typical Culture Collection (ATCC, Rockville, USA). The cells were grown as previously described [ 33 ]. Cells treated with XCT790 (Sigma-Aldrich, St. Louis, MO, USA) were incubated in phenol red-free medium (Thermo Fisher) containing 1% Serum Replacement 2 (Sigma-Aldrich).…”

“…Total RNA was isolated according to the manufacturer’s protocol (Invitrogen, USA, Thermal), as previously described [ 33 ]. The mRNA was transcribed into cDNA using an Access RT-PCR System (Promega, USA).…”

“…Whole-cell proteins were extracted according to the manufacturer’s protocol (Clontech, Palo Alto, USA) and their concentration was determined using an ELISA kit (Pierce), as previously described [ 33 ]. Thirty micrograms of whole-cell protein lysate was loaded to each lane of an 8%-polyacrylamide gel.…”

miR‐522 facilitates the prosperities of endometrial carcinoma cells by directly binding to monoamine oxidase B

“…Endometrial carcinoma is a kind of lethal malignant tumor arising from the endometrium and mainly occurs among women with an increasing morbidity and mortality around the world. [1][2][3][4] Despite the improvements in survival rates of patients with endometrial carcinoma, the prognosis of patients remains tricky. 1,5 Most patients have lost the optimal treatment period when the diagnosis is identified.…”

Key regulator of cellular metabolism, estrogen-related receptor &alpha;, a new therapeutic target in endocrine-related gynecological tumor

“…Although these compounds have not been used clinically, they play a key role in exploring the biological role of ERRα and the pathways involved. The first selective ERRα antagonist, XCT790, can bind ERRα and blocking its interaction with coactivators, downregulating the expression of target genes for ERRɑ, and inhibiting cell proliferation in vitro 35,75,76…”