Abstract
Apoptosis is an important process that directly affects the response of cancer cells to anticancer drugs. Among different factors involved in this process, the BcL-xL protein plays a critical role in inhibiting apoptosis induced by chemotherapy agents. Henceforth, its downregulation may have a synergistic activity that lowers the necessary dose of anticancer agents. In this study, anti-Bcl-xL siRNA were formulated within an EGFR-targeted nanomedicine with scFv ligands (NM-scFv) and its activity was tested in the non-small cell lung cancer (NSCLC) cell line H460. The obtained NMs-scFv anti-Bcl-xL were suitable for intravenous injection with sizes around 100 nm, a high monodispersity level and good siRNA complexation capacity. The nanocomplex's functionalization with anti-EGFR scFv ligands was shown to allow an active gene delivery into H460 cells and led to approximately 63% of gene silencing at both mRNA and protein levels. The NM-scFv anti-Bcl-xL improved the apoptotic activity of cisplatin and reduced the cisplatin IC(50) value in H460 cells by a factor of around three from 0.68 ± 0.12 μM to 2.21 ± 0.18 μM (p < 0.01), respectively, in comparison to that of NM-scFv formulated with control siRNA (p > 0.05).