Suppression of EGFR expression by antisense or small interference RNA inhibits U251 glioma cell growth in vitro and in vivo

Abstract

Epidermal growth factor receptor (EGFR) had been reported as one of the major responsible genes for malignant progression and phenotype reversion of gliomas, and has been used as one of the most important therapeutic targets. In the present study, small interference RNA (siRNA) and antisense EGFR expression constructs, which target sequences of human EGFR catalytic domain (2400-2420) and the 3 0 -coding region, respectively, were used to examine the growth inhibition effects on U251 glioma cells. Cell growth was significantly inhibited and G2/M arrest was observed in antisense-and siRNA-treated groups. Matrigel matrix demonstrated spotted cell clustering pattern in antisense-and siRNA-transfected U251 cells, indicating poor cell growth activities. In addition, the tumor volumes in U251 subcutaneous mice model treated with antisense and siRNA were significantly smaller than those treated with control siRNA and phosphate-buffered saline. Also, glial fibrillary acidic protein expression was upregulated in antisense-and siRNA-treated groups than the control groups. Our results demonstrated that antisense-or siRNA-targeting intracellular region of EGFR can inhibit EGFR expression, exerted growth inhibition effect on U251 glioma cells in vitro and in vivo. Consequently, siRNA expression plasmid-mediated gene therapy would be a new strategy in treatment of gliomas.

Inhibition of EGFR pathway signaling and the metastatic potential of breast cancer cells by PA-MSHA mediated by type 1 fimbriae via a mannose-dependent manner

“…Apoptosis has also been proven to be prominently increased in EGFR anti-sense-or siRNA-treated groups, indicating that EGFR is an important way to induce the cascade-dependent apoptosis (Schaerli and Jaggi, 1998;Gibson et al, 1999;Lage et al, 2003;Kang et al, 2006). Our study discovered several novel concepts for biological therapy.…”

Role of the AKT pathway in microRNA expression of human U251 glioblastoma cells

“…Western immunoblot analysis was used to confirm siRNA of AKT in U251 cells. Protein extracts (20 μg) from each sample were run on SDS-PAGE as previously described (23). After blocking, the membranes were incubated with mouse anti-AKT and anti-phospho-AKT monoclonal antibody (both in 1:1,000), NF-κB (1:1,000), c-Myc (1:1,000) or ß-actin (1:2,000, Santa Cruz Biotechnology, Santa Cruz, CA).…”

Photochemically stimulated drug delivery increases the cytotoxicity and specificity of EGF–saporin

“…Antibody dependent cellular cytotoxicity is, in addition, suggested to be an important mechanism for cetuximabinduced cytotoxicity in vivo (Naramura et al 1993, Kurai et al 2007). Other EGFR targeting strategies are under development for therapeutic use such as utilization of EGFR specific siRNA (Kang et al 2006, Yamanaka et al 2008), EGFR targeted Receptor recycling 4) Cellular activation P P P P P P P P P P P P P P P P P P P P P P P P…”