Involvement of estrogen receptor β in androgen receptor-induced growth inhibition in prostate cancer PC-3 cells

Abstract

Previous studies have suggested that changes in sex hormone receptor expression may be associated with the initiation and progression of prostate cancer (PCa). Therefore, the present study aimed to investigate the association and possible pathways between two sex hormone receptors and PCa by measuring the expression levels of the androgen receptor (AR) and the estrogen receptor subtypes alpha (ERα) and beta (ERβ) in prostatic cancer PC-3 cell lines. The pcDNA3.1-hERβ plasmid was transfected into PC-3 cell lines. The expression levels of AR, ERα and ERβ were detected at the mRNA level by reverse transcription-polymerase chain reaction (RT-PCR) and quantitative PCR (qPCR). The results demonstrated that the expression levels of AR, ERβ and ERα were downregulated to different degrees: ERβ test group vs. PC-3 cell group (P=0.000; 95% confidence interval: 0.9803–1.6331). ERβ and AR expression was detected continuously in the PC-3 cells, but the expression of ERα was not. AR expression levels exhibited an upward trend whilst the expression of ERβ demonstrated a marked downward trend. There is a correlation between the expression levels of ERβ and the incidence of PCa, and ERβ may inhibit the growth of PC-3 cell lines by regulating the expression levels of AR. ERβ may provide a novel target for PCa therapies.

<p>Estrogen Receptor Beta Inhibits The Proliferation, Migration, And Angiogenesis Of Gastric Cancer Cells Through Inhibiting Nuclear Factor-Kappa B Signaling</p>

“…ERβ is a specific estrogen receptor that acts as a tumor suppressor in diverse cancers, including colon cancer, breast cancer, ovarian cancer, and prostate cancer 6–9. A previous study has proved that the expression of ERβ is significantly lower in GC tissues than in normal tissues 14.…”

“…Estrogen receptor beta (ERβ) is a hormone-inducible transcription factor that downregulated in diverse cancers, such as colon cancer,6 breast cancer,7 ovarian cancer,8 and prostate cancer 9. A large number of previous studies have proved that ERβ plays a key regulatory role in the occurrence and development of cancers.…”

Signal Crosstalk and the Role of Estrogen Receptor beta (ERβ) in Prostate Cancer

“…Androgen signaling is critical in prostate cancer, but the mechanism is poorly understood, and ERβ may play an important function in the AR signaling pathway. Recent investigations have shown that androgen-activated androgen receptors can interact not only directly through binding to estrogen response elements, but also indirectly with SP-1 (specificity protein-1), AF-1 (activation protein-1), and nuclear factor κB proteins by binding to the corresponding ligands and regulating AR signaling at the transcriptional or post-transcriptional level, which in turn affects prostate cancer progression [ 32 – 35 ]. Researchers found elevated epithelial hyperplasia and AR downstream genes level in a ERβ knockout mouse model, most of which were also upregulated in prostate cancer, prompting consideration of whether crosstalk exists between these 2 signaling pathways [ 36 ].…”