Chemosensitization of solid tumors by inhibition of Bcl-xL expression using DNAzyme.

DNAzymes are a novel class of gene suppressors that selectively bind to an RNA substrate by Watson-Crick base pairing and cleave phosphodiester bonds. To explore the potential for therapeutic use of catalytic DNA molecules, active DNAzymes targeting the bcl-xL gene were generated through a multiplex in vitro selection. The DNAzyme-mediated down-regulation of the bcl-xL expression was demonstrated in various cancer cell lines by Western blots.

Broad-spectrum and virus-specific nucleic acid-based antivirals against influenza.

Rapid increase in drug-resistant influenza virus isolates, and pandemic threat posed by highly pathogenic avian influenza A and swine flu viruses provide clear and compelling reasons for fast tracking development of novel antiviral drugs. Nucleic acid-based drugs represent a promising class of novel antiviral agents that can be designed to target various seasonal, pandemic and avian influenza viruses. Nucleic acids can be designed to elicit broad-spectrum antiviral responses in the host, by suppressing viral gene expression, or by inducing cleavage or degradation of viral RNA.

Recent patents in antiviral siRNAs.

The advent of gene silencing siRNA technology has created opportunities to develop therapeutics based on targeting the genomics of the disease state. Amongst the first applications of siRNA technology, antiviral applications have been quickly and extensively exploited allowing emergence of a range of antiviral therapeutic strategies. Patent activity has encompassed a range of the components required to utilize this technology ranging from the identification of susceptible genomic targets through to the development of vector systems to express the siRNA endogenously or the synthesis of stable RNA oligonucleotides for in vivo therapeutics.

Recent Patents on development of nucleic acid-based antiviral drugs against seasonal and pandemic influenza virus infections.

Influenza viruses are etiological agents of deadly flu that continue to pose global health threats, and have caused global pandemics that killed millions of people worldwide. The global crisis involving the avian H5N1 influenza provides compelling reasons to accelerate fast track development of novel antiviral drugs against the potential pandemic virus. The availability of neuraminidase inhibitors such as oseltamivir (tamiflu) improves our ability to defend against influenza viruses, but the incidences of tamiflu-resistance are rising rapidly.

Brothers in arms: DNA enzymes, short interfering RNA, and the emerging wave of small-molecule nucleic acid-based gene-silencing strategies.

The past decade has seen the rapid evolution of small-molecule gene-silencing strategies, driven largely by enhanced understanding of gene function in the pathogenesis of disease. Over this time, many genes have been targeted by specifically engineered agents from different classes of nucleic acid-based drugs in experimental models of disease to probe, dissect, and characterize further the complex processes that underpin molecular signaling. Arising from this, a number of molecules have been examined in the setting of clinical trials, and several have recently made the successful transition from the bench to the clinic, heralding an exciting era of gene-specific treatments.