SIU 2017: Demystifying the Mechanistic and Functional Aspects of RNA Activation With Double-Stranded RNAs in Human Prostate Cancer Cells

Lisbon, Portugal (UroToday.com) The recently identified phenomenon of double-stranded RNA (dsRNA)-mediated gene activation (RNAa) has been studied extensively. It is present in humans, mice, and Caenorhabditis elegans, suggesting that dsRNA-mediated RNAa is an evolutionarily mechanism. 

Previous studies showed that dsP21-322 has the capacity to induce tumor suppressor gene p21 expression in human prostate cancer cells. Nonetheless, the role of dsRNAs in the activation of gene expression, including their target molecules and associated key factors, remains poorly
understood.

In this study, human prostate cancer cell lines PC-3 and DU-145 were analyzed. Oligonucleotides were used to overexpress dsRNAs and dsControl. Real-time PCR and Western blot were used to detect mRNA and protein expression, respectively. Using fluorescence microscopy the authors examined the kinetics of dsRNA subcellular distribution. Using a well-characterized antibody that recognizes biotin protein, they performed Chromatin immunoprecipitation (ChIP) to detect the molecular target for dsR21-322. Luciferase reporter assay was further performed to verify dsRNAs target molecules. Furthermore, Co-immunoprecipitation, sliver-staining, Tandem mass spectrometry, and ChIP assay were all carried out to identify unknown proteins and whether histone modification are involved in saRNA-mediated p21 expression.

It was demonstrated that dsRNA-mediated p21 induction in human cell lines is a common phenomenon. This process occurs at the transcriptional level and that the complementary p21 promoter is the intended dsRNA target. Additionally, the authors recognized that several heterogeneous nuclear ribonucleoproteins (hnRNPs) associate with the dsP21-322. 

In conclusion, these data reveal the mechanistic and functional aspects of ncRNA-mediated p21 activation in human prostate cancer cells. This might be a useful tool to analyze gene function and aid in the development of novel drug targets for prostate cancer treatment.

Presented by: Hu, J.

Written by: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre.Twitter: @GoldbergHanan at the 37th Congress of Société Internationale d’Urologie - October 19-22, 2017- Lisbon, Portugal