MiRNAs and tempol therapeutic potential in prostate cancer: a preclinical approach

This study investigated tempol action on genes and miRNAs related to NFκB pathway in androgen dependent or independent cell lines and in TRAMP model in the early and late-stages of cancer progression. A bioinformatic search was conducted to select the miRNAs to be measured based on the genes of interest from NFκB pathway. The miR-let-7c-5p, miR-26a-5p and miR-155-5p and five target genes (BCL2, BCL2L1, RELA, TNF, PTGS2) were chosen for RT-PCR and gene enrichment analyses. In vitro, PC-3 and LNCaP cells were exposed, respectively, to 1.0 or 2.0 mM of tempol during 48 h. In vivo, five experimental groups were evaluated regarding tempol effects in the early (CT12 and TPL12 groups) and late-stages (CT20, TPL20-I and TLP20-II) of PCa development. TPL groups were treated with 50 mg/kg or 100 mg/kg of tempol. The ventral lobe of the prostate and the plasma was collected. Tempol treatment increased miRs expression in PC-3 and LNCaP. For both cell lines, tempol decreased RELA expression. In TRAMP model, tempol increased miRNA expression in prostate for all treated groups. Tempol upregulated the miRNA expressions related to the NFκB pathway in the prostate tissue and human tumor cell lines. Their increase is mainly linked to increased cell death and delayed CaP aggressivenes. Thus, tempol's capacity for miRNA-mediated gene silencing to decrease tissue proliferation and cell survival processes is part of its tissue mechanics.