Upregulation of LHPP by saRNA inhibited hepatocellular cancer cell proliferation and xenograft tumor growth.

Hepatocellular carcinoma (HCC) is the most common primary liver cancer worldwide and no pharmacological treatment is available that can achieve complete remission of HCC. Phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP) is a recently identified HCC tumor suppressor gene which plays an important role in the development of HCC and its inactivation and reactivation has been shown to result in respectively HCC tumorigenesis and suppression. Small activating RNAs (saRNAs) have been used to achieve targeted activation of therapeutic genes for the restoration of their encoded protein through the RNAa mechanism.

p21CIP/WAF1 saRNA inhibits proliferative vitreoretinopathy in a rabbit model.

Purpose: Proliferative vitreoretinopathy (PVR) is a disease process resulting from proliferation of retinal pigment epithelial (RPE) cells in the vitreous and periretinal area, leading to periretinal membrane formation and traction and eventually to postoperative failure after vitreo-retinal surgery for primary rhegmatogenous retinal detachment (RRD). The present study was designed to test the therapeutic potential of a p21CIP/WAF1 (p21) inducing saRNA for PVR.

Methods: A chemically modified p21 saRNA (RAG1-40-53) was tested in cultured human RPE cells for p21 induction and for the inhibition of cell proliferation, migration and cell cycle progression.

Small activating RNA activation of ATOH1 promotes regeneration of human inner ear hair cells.

The loss of inner ear hair cells leads to irreversible acoustic injury in mammals, and regeneration of inner ear hair cells to restore hearing loss is challenging. is a key gene in the development and regeneration of hair cells. Small activating RNAs (saRNAs) can target a gene to specifically upregulate its expression.

Lipoxin A methyl ester protects PC12 cells from ketamine-induced neurotoxicity via the miR-22/BAG5 pathway.

Objective: Ketamine is an anesthetic that induces neurotoxicity when administered at high doses. In this work, we explored the protective effects of lipoxin A methyl ester (LXA ME) against ketamine-induced neurotoxicity and the underlying protective mechanism in pheochromocytoma (PC12) cells.

Methods: PC12 cells were treated with 50 μM of ketamine and different LXA ME concentrations of LXA4 ME (5-50 nM) for 24 h, and their viability, apoptosis, and oxidative status were assessed.

Visualization of subdiffusive sites in a live single cell.

We measured anomalous diffusion in human prostate cancer cells which were transfected with the Alexa633 fluorescent RNA probe and co-transfected with enhanced green fluorescent protein-labeled argonaute2 protein by laser scanning microscopy. The image analysis arose from diffusion based on a "two-level system". A trap was an interaction site where the diffusive motion was slowed down.

Small activating RNA induced expression of VHL gene in renal cell carcinoma.

Recent studies have reported that chemically synthesized double-stranded RNAs (dsRNAs), also known as small activating RNA (saRNAs), can specifically induce gene expression by targeting promoter sequences by a mechanism termed RNA activation (RNAa). In the present study, we designed 4 candidate saRNAs targeting the Von Hippel-Lindau (VHL) gene promoter. Among these saRNAs, dsVHL-821 significantly inhibited cell growth by up-regulating VHL at both the mRNA and protein levels in renal cell carcinoma 769-P cells.

Development of Therapeutic dsP21-322 for Cancer Treatment.

Small activating RNAs (saRNAs) are a class of artificially designed short duplex RNAs targeted at the promoter of a particular gene to upregulate its expression via a mechanism known as RNA activation (RNAa) and hold great promise for treating a wide variety of diseases including those undruggable by conventional therapies. The therapeutic benefits of saRNAs have been demonstrated in a number of preclinical studies carried out in different disease models including cancer. With many tumor suppressor genes (TSGs) downregulated due to either epigenetic mechanisms or haploinsufficiency resulting from deletion/mutation, cancer is an ideal disease space for saRNA therapeutics which can restore the expression of TSGs via epigenetic reprogramming.

Small RNA-Guided Transcriptional Gene Activation (RNAa) in Mammalian Cells.

Small RNA partnering with Argonaute (Ago) proteins plays important roles in diverse biological processes mainly by suppressing the expression of cognate target sequences. Mounting evidence reveals that the small RNA-Ago pathway can also positively regulate gene expression, a phenomenon termed as RNA activation (RNAa), which is evolutionarily conserved from Caenorhabditis elegans to human. In this chapter, I provide a general overview of mammalian RNAa phenomena and their basic characteristics and discuss recent advances toward understanding the nature of the molecular machinery responsible for RNAa and the development of RNAa-based research tools and therapeutics.

Enhancing DPYSL3 gene expression via a promoter-targeted small activating RNA approach suppresses cancer cell motility and metastasis.

To explore a novel strategy in suppressing tumor metastasis, we took the advantage of a recent RNA activation (RNAa) theory and used small double-strand RNA molecules, termed as small activating RNAs (saRNA) that are complimentary to target gene promoter, to enhance transcription of metastasis suppressor gene. The target gene in this study is Dihydro-pyrimidinase-like 3 (DPYSL3, protein name CRMP4), which was identified as a metastatic suppressor in prostate cancers. There are two transcriptional variants of DPYSL3 gene in human genome, of which the variant 2 is the dominant transcript (DPYSL3v2, CRMP4a) but is also significantly down-regulated in primary prostate cancers.

saRNA-guided Ago2 targets the RITA complex to promoters to stimulate transcription.

Small activating RNAs (saRNAs) targeting specific promoter regions are able to stimulate gene expression at the transcriptional level, a phenomenon known as RNA activation (RNAa). It is known that RNAa depends on Ago2 and is associated with epigenetic changes at the target promoters. However, the precise molecular mechanism of RNAa remains elusive.

Inducing gene expression by targeting promoter sequences using small activating RNAs.

Vector-based systems comprised of exogenous nucleic acid sequences remain the standard for ectopic expression of a particular gene. Such systems offer robust overexpression, but have inherent drawbacks such as the tedious process of construction, excluding sequences (e.g.

RNAa in action: from the exception to the norm.

Small RNA programmed Argonautes are sophisticated cellular effector platforms known to be involved in a diverse array of functions ranging from mRNA cleavage, translational inhibition, DNA elimination, epigenetic silencing, alternative splicing and even gene activation. First observed in human cells, small RNA-induced gene activation, also known as RNAa, involves the targeted recruitment of Argonaute proteins to specific promoter sequences followed by induction of stable epigenetic changes which promote transcription. The existence of RNAa remains contentious due to its elusive mechanism.

Up-regulation of p21(WAF1/CIP1) by miRNAs and its implications in bladder cancer cells.

We have previously reported that synthetic dsRNA can activate p21 expression by targeting the p21 promoter, thereby suppressing the proliferation of human bladder cancer cells. As complementarity between dsRNA and its target sequences is necessary for RNA activation, miRNAs may also trigger p21 expression through the same mechanism. Here, the expression levels of three miRNAs (miR-370, miR-1180 and miR-1236) decreased in bladder cancer tissues compared to healthy controls and the levels of these mRNAs positively correlated with p21 mRNA levels.

Regulatory Variants and Disease: The E-Cadherin -160C/A SNP as an Example.

Single nucleotide polymorphisms (SNPs) occurring in noncoding sequences have largely been ignored in genome-wide association studies (GWAS). Yet, amounting evidence suggests that many noncoding SNPs especially those that are in the vicinity of protein coding genes play important roles in shaping chromatin structure and regulate gene expression and, as such, are implicated in a wide variety of diseases. One of such regulatory SNPs (rSNPs) is the E-cadherin (CDH1) promoter -160C/A SNP (rs16260) which is known to affect E-cadherin promoter transcription by displacing transcription factor binding and has been extensively scrutinized for its association with several diseases especially malignancies.

Identification of small activating RNAs that enhance endogenous OCT4 expression in human mesenchymal stem cells.

Ectopic overexpression of transcription factors has been used to reprogram cell fate. For example, virus-mediated overexpression of four transcription factors OCT4, SOX2, MYC, and KLF4, known as Yamanaka factors, can convert somatic cells to induced pluripotent stem (iPS) cells. However, gene-specific switch-on of endogenous gene production without the use of foreign DNA remains a challenge.

Demystifying the nuclear function of Argonaute proteins.

The Argonaute family of proteins is highly evolutionarily conserved and plays essential roles in small RNA-mediated gene regulatory pathways and in a wide variety of cellular processes. They were initially discovered by genetics studies in plants and have been well characterized as key components of gene silencing pathways guided by small RNAs, a phenomenon known as RNA interference. Conventionally, guided by different classes of small RNAs, Argonautes bind to and silence homologous target sequences at the post-transcriptional level.

miR-663 induces castration-resistant prostate cancer transformation and predicts clinical recurrence.

Castration-resistant prostate cancer (CRPC) and its treatment are challenging issues in prostate cancer management. Here, we report that miR-663 is upregulated in CRPC tissues. Overexpression of miR-663 in prostate LNCaP cells promotes cell proliferation and invasion, neuroendocrine differentiation, and reduction in dihydrotestosterone-induced upregulation of prostate-specific antigen expression.

Chromatin remodeling by the small RNA machinery in mammalian cells.

Chromatin states, quite different from changes in DNA sequence, can impact fundamental cellular processes such as determination of cell identity and development of disease. However, how chromatin states are established and regulated remain to be fully elucidated. In several lower eukaryotes, the small RNA machinery comprised of small RNA and its partners, the Argonaute proteins, is known to play important roles in the establishment of heterochromatin and silencing of repetitive sequences.

Ago1 Interacts with RNA polymerase II and binds to the promoters of actively transcribed genes in human cancer cells.

Argonaute proteins are often credited for their cytoplasmic activities in which they function as central mediators of the RNAi platform and microRNA (miRNA)-mediated processes. They also facilitate heterochromatin formation and establishment of repressive epigenetic marks in the nucleus of fission yeast and plants. However, the nuclear functions of Ago proteins in mammalian cells remain elusive.

Targeted induction of endogenous NKX3-1 by small activating RNA inhibits prostate tumor growth.

Background: RNA activation (RNAa) is a small RNA-mediated gene regulation mechanism by which expression of a particular gene can be induced by targeting its promoter using small double-stranded RNA also known as small activating RNA (saRNA). We used saRNA as a molecular tool to examine NKX3-1's role as a tumor suppressor and tested in vitro and in vivo antitumor effects of NKX3-1 induction by saRNA.

Materials And Methods: NKX3-1 saRNA was transfected into human prostate cancer cells including LNCaP, CWR22R, PC-3, CWR22RV1, DuPro, LAPC4, and DU145.

saRNA guided iNOS up-regulation improves erectile function of diabetic rats.

Purpose: Promoter targeted saRNAs mediate sequence specific up-regulation of gene expression. We explored the therapeutic effect of RNA activation mediated iNOS gene activation on improving erectile function in a rat model of diabetes mellitus.

Materials And Methods: An optimal saRNA sequence specific for iNOS promoter was cloned into an adenoviral vector, resulting in AdU6/shiNOS and AdU6/shControl.

Formulation of Small Activating RNA Into Lipidoid Nanoparticles Inhibits Xenograft Prostate Tumor Growth by Inducing p21 Expression.

Application of RNA interference (RNAi) in the clinic has improved with the development of novel delivery reagents (e.g., lipidoids).

Adaptation and clonal selection models of castration-resistant prostate cancer: current perspective.

Prostate cancer is a leading cause of cancer deaths in men worldwide. Management of the disease has remained a great challenge and even more so is the aggressive advanced stage with castration-resistant behavior. The mechanisms and timing of development of castration-resistant prostate cancer are unclear and remain debatable.

Small RNA and its application in andrology and urology.

Small non-coding RNAs such as small interfering RNA (siRNA), microRNA (miRNA) and piwi-interacting RNA (piRNA) exist in almost all kingdoms of organisms and have recently emerged as master regulators of gene expression to affect a diverse range of important biological processes. They exert their functions largely through two related but opposing mechanisms: RNA interference (RNAi) mediated by siRNA, miRNA and piRNA, and RNA activation (RNAa) mediated by small activating RNA (saRNA) and miRNA, leading to silencing and overexpression of target genes respectively. Dysregulation of these mechanisms have been implicated in a variety of human diseases including urological and andrological diseases.