title: Resveratrol and pterostilbene epigenetically restore PTEN expression by targeting oncomiRs of the miR-17 family in prostate cancer.
abstract: In recent years, not only has the role of miRNAs in cancer become increasingly clear but also their utilization as potential biomarkers and therapeutic targets has gained ground. Although the importance of dietary stilbenes such as resveratrol and pterostilbene as anti-cancer agents is well recognized, our understanding of their miRNA-targeting capabilities is still limited. In our previous study, we reported that resveratrol downregulates PTEN-targeting members of the oncogenic miR-17 family, which are overexpressed in prostate cancer. This study investigates the resveratrol and pterostilbene induced miRNA-mediated regulation of PTEN in prostate cancer. Here, we show that both compounds decrease the levels of endogenous as well as exogenously expressed miR-17, miR-20a and miR-106b thereby upregulating their target PTEN. Using functional luciferase reporter assays, we demonstrate that ectopically expressed miR-17, miR-20a and miR-106b directly target PTEN 3'UTR to reduce its expression, an effect rescued upon treatment with resveratrol and pterostilbene. Moreover, while stable lentiviral expression of miR-17/106a significantly decreased PTEN mRNA and protein levels and conferred survival advantage to the cells, resveratrol and more so pterostilbene was able to dramatically suppress these effects. Further, pterostilbene through downregulation of miR-17-5p and miR-106a-5p expression both in tumors and systemic circulation, rescued PTEN mRNA and protein levels leading to reduced tumor growth in vivo. Our findings implicate dietary stilbenes as an attractive miRNA-mediated chemopreventive and therapeutic strategy, and circulating miRNAs as potential chemopreventive and predictive biomarkers for clinical development in prostate cancer.
authors: Cancer Institute, University of Mississippi Medical Center, Jackson, Mississippi, USA.
authors: Swati
authors: S
authors: Dhar
authors: Cancer Institute, University of Mississippi Medical Center, Jackson, Mississippi, USA.
authors: Avinash
authors: A
authors: Kumar
authors: United States Department of Agriculture, Agricultural Research Service, Natural Products Utilization Research Unit, University, Mississippi, USA.
authors: Agnes M
authors: AM
authors: Rimando
authors: Center of Biostatistics and Bioinformatics, University of Mississippi Medical Center, Jackson, Mississippi, USA.
authors: Xu
authors: X
authors: Zhang
authors: Cancer Institute, University of Mississippi Medical Center, Jackson, Mississippi, USA.|Department of Pathology, University of Mississippi Medical Center, Jackson, Mississippi, USA.
authors: Anait S
authors: AS
authors: Levenson
mesh_terms: D020413:3' Untranslated Regions; D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry; D045744:Cell Line, Tumor; D002470:Cell Survival; D044127:Epigenesis, Genetic; D015972:Gene Expression Regulation, Neoplastic; D016147:Genes, Tumor Suppressor; D006801:Humans; D007150:Immunohistochemistry; D016086:Lentivirus / Q000235:genetics; D008156:Luciferases / Q000378:metabolism; D008297:Male; D051379:Mice; D035683:MicroRNAs / Q000378:metabolism*; D051059:PTEN Phosphohydrolase / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D000077185:Resveratrol; D013267:Stilbenes / Q000737:chemistry*
chemical_list: D020413:3' Untranslated Regions; D000972:Antineoplastic Agents, Phytogenic; C542541:MIRN106 microRNA, human; C524941:MIRN17 microRNA, human; C534451:MIRN20a microRNA, human; D035683:MicroRNAs; D012333:RNA, Messenger; D013267:Stilbenes; C107773:pterostilbene; D008156:Luciferases; D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human; D000077185:Resveratrol
keywords: PTEN; oncomiRs; prostate cancer epigenetics; pterostilbene; resveratrol