RNA interference and the use of small interfering RNA to study gene function in mammalian systems

Abstract

In the past 2 years, extraordinary developments in RNA interference (RNAi)-based methodologies have seen small interfering RNAs (siRNA) become the method of choice for researchers wishing to target specific genes for silencing. In this review, an historic overview of the biochemistry of the RNAi pathway is described together with the latest advances in the RNAi field. Particular emphasis is given to strategies by which siRNAs are used to study mammalian gene function. In this regard, the use of plasmid-based and viral vector-based systems to mediate long-term RNAi in vitro and in vivo are described. However, recent work has shown that non-specific silencing effects and activation of the interferon response may occur following the use of some siRNA and delivery vector combinations. Future goals must therefore be to understand the mechanisms by which siRNA delivery leads to unwanted gene silencing effects in cells and, in this way, RNAi technology can reach its tremendous potential as a scientific tool and ultimately be used for therapeutic purposes.

Transforming growth factor-β1 and activin A generate antiproliferative signaling in thyroid cancer cells

“…We have shown previously that thyroid tumors express TGFb1, ActA, and SMAD proteins (Kimura et al 1999, Cerutti (Bantounas et al 2004). In this study, the generation of stable cell lines with long-term gene silencing using siRNA expression vector approach (Sui et al 2002) allowed us to investigate the effects of continuous TGF-b1 or ActA knockdown.…”

Lentivirus‐Mediated Small Interfering RNA Targeting VEGF‐C Inhibited Tumor Lymphangiogenesis and Growth in Breast Carcinoma

“…SiRNA technology provides a novel strategy for investigating gene expression and function (Bantounas et al, 2004). Compared with antisense oligonucleotides and ribozymes, siRNA allows us to target any gene with greater specificity and efficiency, and it can be developed in various ways allowing for numerous in vitro and in vivo applications (Elbashir et al, 2001;Chen et al, Fig.…”

Small interfering RNA targeting HMGN5 induces apoptosis via modulation of a mitochondrial pathway and Bcl-2 family proteins in prostate cancer cells

“…Among these approaches, the RNAi-based techniques for silencing specific genes are used more widely. 22 The combination of RNAi and lentiviral transgenesis has been demonstrated to result in efficient and stable knockdown of target genes both in vitro and in vivo. 23 Disruption of HMGN5 results in potent anti-tumor effects in an in vivo mouse model using DU145 cells (androgen-independent prostate cancer cells), 15 suggesting that targeting of HMGN5 inhibits DU145 cell proliferation in vivo.…”