Current Pharmaceutical Design - Volume 14, Issue 34, 2008

Oligonucleotide-based therapeutic drugs of current interest include tools related to RNA interference (RNAi) such as short interfering RNA (siRNA), short hairping RNA (shRNA), or micro RNA (miRNA) as well as catalytic RNA and antisense oligonucleotides (asON). Based on resolved molecular patho-mechanisms of diseases and the causative involvement of genes in the development of diseases, their advantages include the m Read More

RNAi interference (RNAi) is an almost standard method for the knockdown of any target gene of interest in vitro, exploring a naturally occurring catalytic mechanism. Beyond functional analyses, the downregulation of pathologically relevant genes which are aberrantly expressed in a given disease will offer novel therapeutic approaches, also with regard to otherwise ‘undruggable’ genes. RNAi is mediated by small interferin Read More

The accessibility to topical administration through inhalation, combined with its large surface area, has led to speculation that the lung might offer an ideal target for the application of oligonucleotide based therapeutics. In this review, we shall critically examine the challenges facing antisense and siRNA based approaches for target validation in vivo and as potential therapeutics. In particular, we shall discuss the antisense and Read More

Classical pharmaceutical research and development relies on the identification and validation of i) membranepermeable small molecules or ii) extracellular targets that are able to interfere with cellular key signaling pathways. During the last two decades the direct intracellular delivery of macromolecules developed into a novel paradigm to manipulate cell functions. This technique, commonly referred to as protein transdu Read More

Cellular uptake of therapeutic oligonucleotides and subsequent intracellular trafficking to their target sites represents the major technical hurdle for the biological effectiveness of these potential drugs. Accordingly, laboratories worldwide focus on the development of suitable delivery systems. Among the different available non-viral systems like cationic polymers, cationic liposomes and polymeric nanoparticles, cell-penetrating Read More

One of the major challenges for new therapeutics molecules to enter the clinic remains improving their bioavailability and cellular uptake. Therefore, delivery has become a key stone in therapeutic development and several technologies have been designed to improve cellular uptake of therapeutic molecules, including cell-penetrating peptides (CPPs) or protein transduction domain (PTD). PTDs or CPPs were discovered t Read More

The phosphorothioate(PS)-stimulated cellular uptake of naked short interfering RNA (siRNA) into mammalian cells indicates a promising new mechanistic strategy because it makes use of a caveosomal, rather than an endosomal pathway, which is used by the majority of known delivery systems. This PS-stimulated mode delivers large amounts of siRNA primarily into the perinuclear space which is related to measurable t Read More

RNA interference (RNAi) is an evolutionary conserved post-transcriptional gene silencing mechanism, in which double stranded RNA effector molecules trigger the degradation of complementary mRNA transcripts. The use of RNAi to reduce gene expression with high specificity and ready availability is a powerful tool for reverse genetics and provides great therapeutic potential for targeting diseases caused by the expressi Read More

The prospect of introducing siRNA in a cell, to induce silencing of the corresponding gene, has encouraged research into RNAi-based therapeutics as treatment for human diseases. At present, the siRNA molecules that are in a more advanced stage of clinical evaluation have a common factor: all are delivered locally at the site of the disease. Thus, the state of the art in delivery of siRNA appears to be the local administration. Th Read More