Intended transcriptional gene silencing with siRNA to the human Vascular Endothelial Growth Factor (VEGF) promoter results in VEGF repression through sequence-specific off-targeting

SiRNA designed to target the human VEGF gene promoter revealed a putative candidate for transcriptional gene silencing. However, mutation or deletion of the target site demonstrated that the observed VEGF knockdown was the result of a sequence-specific off-target effect. Bioinformatic and microarray analyses of genes implicated in VEGF transcriptional control followed by knockdown and Western blotting experiments presented one candidate, GRB2, as an unintended target of the VEGF promoter-specific siRNA.