Project description:In castration-resistant prostate cancer (CRPC), clinical response to androgen receptor (AR) antagonists is limited mainly due to AR-variants expression and restored AR signaling. The metabolite spermine is most abundant in prostate and it decreases as prostate cancer progresses, but its functions remain poorly understood. Here, we show spermine inhibits full-length androgen receptor (AR-FL) and androgen receptor splice variant 7 (AR-V7) signaling and suppresses CRPC cell proliferation by directly binding and inhibiting protein arginine methyltransferase PRMT1. Spermine reduces H4R3me2a modification at the AR locus and suppresses AR binding as well as H3K27ac modification levels at AR target genes. Spermine supplementation restrains CRPC growth in vivo. PRMT1 inhibition also suppresses AR-FL and AR-V7 signaling and reduces CRPC growth. Collectively, we demonstrate spermine as an anticancer metabolite by inhibiting PRMT1 to transcriptionally inhibit AR-FL and AR-V7 signaling in CRPC, and we indicate spermine and PRMT1 inhibition as powerful strategies overcoming limitations of current AR-based therapies in CRPC.
Project description:Aberrant androgen receptor (AR)-mediated transcription is a critical driver in progression of human prostate cancer. It's known that different doses of androgens can elicit differential transcriptional and proliferative responses in prostate-tumor cells. Here, we set out to examine the androgenic regulation of glycoprotein expression in the membrane fraction of prostate-tumor cells that could serve as mediators or markers of androgen-induced proliferative responses observed in prostate-tumor cells. A bioanalytical workflow involving lectin-affinity chromatography and label-free quantitative mass spectrometry was used to identify androgen-sensitive glycomembrane protein expression associated with androgen-mediated proliferation. This study would facilitate the identification of surface membrane proteins involved in androgen-mediated proliferation and provide potential therapeutic targets in the detection treatment of proliferation prostate-tumors.
Project description:This SuperSeries is composed of the following subset Series: GSE30622: Dual Role of FoxA1 in Androgen Receptor Binding to Chromatin, Androgen Signaling and Prostate Cancer [Expression Array] GSE30623: Dual Role of FoxA1 in Androgen Receptor Binding to Chromatin, Androgen Signaling and Prostate Cancer [ChIP_seq, DHS_seq] Refer to individual Series
Project description:5α-androstane-3α,17β-diol (3α-diol) is reduced from the potent androgen, 5α-dihydrotestosterone (5α-DHT), by reductive 3α-hydroxysteroid dehydrogenases (3α-HSDs). 3α-diol is believed to be a weak androgen, and has to be oxidized to 5α-DHT before it can exert its androgenic activity on androgen target tissues including the prostate. However, we repeatedly demonstrated that 3α-diol can be a potent androgen, activates cytoplasmic signaling pathway, and may be responsible for androgen-independent prostate cancer growth. A cancer-specific, cDNA-based membrane array was used to determine 3α-diol-mediated gene expressions in prostate cancer progression. Several canonical pathways appeared to be affected by 3α-diol-regulated signaling in LNCaP cells; among them are apoptosis signaling, PI3K/Akt signaling, and death receptor signaling pathways. Biological analysis of 3α-diol-activated signaling confirmed that 3α-diol augmented PI3K/Akt activation can be independent from the classical androgen receptor (AR) signaling. These observations sustained our previous report that 3α-diol continues to supported prostate cell survival and proliferation regardless the status of the AR. We provided the first global analysis of 3α-diol-activated gene expressions and identified cytoplasmic signaling pathways as important components of this response in human prostate cells. 3α-diol may play, therefore, a significant role for transition from androgen-dependent to androgen-independent prostate cancer progression in the presence of androgen blockade. Keywords: array, time course, androgen, prostate, cancer
Project description:Prostate cancer is the most common cancer in men and androgen receptor (AR) downstream signalings promote prostate cancer cell proliferation. To investigate the AR signaling, we performed directional RNA sequence analysis in AR positive prostate cancer cell line, LNCaP and VCaP. Using Noncode and GENCODE data sets. We identified androgen-regulated long non-coding RNAs (lncRNAs) in prostate cancer cells. Directional RNA sequence analysis of androgen-regulated lncRNAs in prostate cancer cells
Project description:Vitamin D induces anti-proliferative and differentiating effects in prostate cancer. Thus calcitriol, the hormonally active form of Vitamin D, and its analogs have been extensively studied in prostate cancer cells. Yet despite its importance, relatively little is known about the genome-scale mechanisms by which Vitamin D, through its cognate nuclear vitamin D receptor (VDR), exerts its regulatory functions at the genomic level. In this study, we defined VDR transcriptional networks in the LNCaP prostate cancer cell line by mapping the genomic binding sites of VDR and by identifying differentially expressed genes upon calcitriol treatment. We found that VDR and androgen receptor (AR) antagonistically regulate a subset of cell cycle-related genes that are over-expressed in prostate cancer tumors. The expression balance of these genes is partially regulated through the competition dynamics between AR and VDR binding to shared cis-regulatory elements. On such shared elements, we found that FOXA1 mediates this competition by serving as a pioneering factor for both AR and VDR binding. We also found significant enrichment of AR-, VDR-, and AR/VDR overlapping binding sites in prostate cancer-associated single-nucleotide polymorphism (SNP) intervals identified from genome-wide association studies (GWAS), providing genetic evidence to link AR, VDR and their crosstalk to prostate cancer susceptibilities. In particular, we found that in a cis-regulatory element of the RFX6 gene implicated in prostate cancer progression, an allelic variant increases prostate cancer risk by switching the antagonism between AR and VDR into a synergistic interaction. Gene expression profiling in LNCaP cells after 24hr treatment with different nuclear recpetor ligrands, with time-matching control, in triplicates Expression is assayed with Agilent G4112F.