Journal Article

PCA3 noncoding RNA is involved in the control of prostate-cancer cell survival and modulates androgen receptor signaling

Nasciutti, Luiz Eurico, Gimba, Etel Rodrigues Pereira, Palumbo, Antonio, de Oliveira, Felipe Leite, de Mello, Kivvi Duarte, Sternberg, Cinthya, Neves, Adriana Freitas, Goulart, Luiz Ricardo, Ferreira, Luciana Bueno, Caetano, Mauricio S

2012

Overview

Background PCA3 is a non-coding RNA (ncRNA) that is highly expressed in prostate cancer (PCa) cells, but its functional role is unknown. To investigate its putative function in PCa biology, we used gene expression knockdown by small interference RNA, and also analyzed its involvement in androgen receptor (AR) signaling. Methods LNCaP and PC3 cells were used as in vitro models for these functional assays, and three different siRNA sequences were specifically designed to target PCA3 exon 4. Transfected cells were analyzed by real-time qRT-PCR and cell growth, viability, and apoptosis assays. Associations between PCA3 and the androgen-receptor (AR) signaling pathway were investigated by treating LNCaP cells with 100 nM dihydrotestosterone (DHT) and with its antagonist (flutamide), and analyzing the expression of some AR-modulated genes (TMPRSS2, NDRG1, GREB1, PSA, AR, FGF8, CdK1, CdK2 and PMEPA1). PCA3 expression levels were investigated in different cell compartments by using differential centrifugation and qRT-PCR. Results LNCaP siPCA3-transfected cells significantly inhibited cell growth and viability, and increased the proportion of cells in the sub G0/G1 phase of the cell cycle and the percentage of pyknotic nuclei, compared to those transfected with scramble siRNA (siSCr)-transfected cells. DHT-treated LNCaP cells induced a significant upregulation of PCA3 expression, which was reversed by flutamide. In siPCA3/LNCaP-transfected cells, the expression of AR target genes was downregulated compared to siSCr-transfected cells. The siPCA3 transfection also counteracted DHT stimulatory effects on the AR signaling cascade, significantly downregulating expression of the AR target gene. Analysis of PCA3 expression in different cell compartments provided evidence that the main functional roles of PCA3 occur in the nuclei and microsomal cell fractions. Conclusions Our findings suggest that the ncRNA PCA3 is involved in the control of PCa cell survival, in part through modulating AR signaling, which may raise new possibilities of using PCA3 knockdown as an additional therapeutic strategy for PCa control.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Analysis / Androgen receptors / Androgens / Antibiotics / Antigens, Neoplasm - genetics / Antigens, Neoplasm - metabolism / Antisense RNA / Apoptosis / Associations, institutions, etc / Biomedical and Life Sciences / Biomedicine / Cancer / Cancer cells / Cancer Research / Care and treatment / Cell culture / Cell cycle / Cell Line, Tumor / Cell survival / Cell Survival - genetics / Centrifugation / Colleges & universities / Cyclin-dependent kinase 2 / Dihydrotestosterone / Exons / Fibroblast growth factor 8 / Fibroblast growth factors / Flutamide / G1 phase / Gene expression / Genes / Genetic aspects / Health Promotion and Disease Prevention / Humans / Immunoblotting / Male / Medicine/Public Health / non-coding RNA / Noncoding DNA / Noncoding RNA / Nuclei / Oncology / PCA3 / Physiological aspects / Prostate cancer / Prostatic Neoplasms - genetics / Prostatic Neoplasms - metabolism / Real-Time Polymerase Chain Reaction / Receptors, Androgen - genetics / Receptors, Androgen - metabolism / Research Article / Reverse Transcriptase Polymerase Chain Reaction / RNA, Small Interfering / RNA, Untranslated - genetics / RNA, Untranslated - metabolism / RNA-mediated interference / Signal transduction / Signal Transduction - genetics / siRNA / Small interfering RNA / Societies / Surgical Oncology / Transfection