Therapeutic potential of decoy oligonucleotides strategy in cardiovascular diseases

HIF-1α decoy oligodeoxynucleotides inhibit HIF-1α signaling and breast cancer proliferation

Although HIF-1α is considered an attractive target for the development of cancer therapies, like other transcriptional factors, it has been regarded as 'undruggable'. The decoy approach is a new class of antigene strategy that can be used to modulate the function of endogenous transcriptional factors. Here, we designed a decoy oligodeoxynucleotide (ODN) and tested its effect on the function of HIF-1α. We found the HIF-1α decoy ODN could efficiently enter into cells. Furthermore, these decoy ODNs can significantly block the expression of VEGFA, a known targeted gene of HIF-1α suggesting that the HIF-1α decoy ODNs can inhibit the function of HIF-1α. More importantly, the HIF-1α decoy ODN induced apoptosis and cell cycle arrest in MDA-MB-231 breast cancer cells. In summary, HIF-1α decoy ODNs can inhibit the function of HIF-1α and induce cancer cell apoptosis. Therefore, HIF-1α decoy ODNs should be further modified to improve their biological activity in vivo.

Transcription factor decoy oligonucleotide-based therapeutic strategy for renal disease

Renal disease, including slight renal injuries, has come to be seen as one of the risk factors for cardiovascular events. At present, most conventional therapy is inefficient, and tends to treat the symptoms rather than the underlying causes of the disorder. Gene therapy based on oligonucleotides (ODN) offers a novel approach for the prevention and treatment of renal diseases. Gene transfer into somatic cells to interfere with the pathogenesis contributing to renal disease may provide such an approach, leading to the better prevention and treatment of renal disease. The major development of gene transfer methods has made an important contribution to an intense investigation of the potential of gene therapy in renal diseases. Amazing advances in molecular biology have provided the dramatic improvement in the technology that is necessary to transfer target genes into somatic cells. Gene transfer methods, especially when mediated by several viral vectors, have improved to a surprising extent. In fact, some (retroviral vectors, adenoviral vectors, or liposome-based vectors, etc.) have already been used in clinical trials. On the other hand, recent progress in molecular biology has provided new techniques to inhibit target gene expression. The transfer of cis-element double-stranded ODN (= decoy) has been reported to be a powerful novel tool in a new class of antigene strategies for gene therapy. The transfer of decoy ODN corresponding to the cis sequence will result in attenuation of the authentic cis-trans interaction, leading to the removal of trans-factors from the endogenous cis-elements with a subsequent modulation of gene expression.

Prospects of antisense oligodeoxynucleotides to alleviate renal ischaemia-reperfusion injury

Renal ischaemia-reperfusion (I/R) injury is a clinically significant problem and an invariable consequence of renal transplantation. The problem begins at the onset of acute tubular necrosis (ATN), when the transplantation takes a long ischaemic interval by using the cardiac arrest donor's kidney. In addition, the longer the ischaemic interval, the higher the incidence rate of ATN. It is clinically important that renal I/R injury is reduced. The antisense oligodeoxynucleotide (AS-ODN), developed as a therapy for intractable diseases at the gene level, has recently been established as an important method in examining specific gene functions. The authors have previously demonstrated that AS-ODN/tissue factor (TF) prevents renal I/R injury. This review discusses the efficacy of AS-ODN/TF and AS-ODN/intercellular adhesion molecule-1 as existing targets, and the potential of AS-ODN/nuclear factor-kappaB, AS-ODN/cyclooxygenase and AS-ODN/5-lipoxygenase as prospective targets.