EGFR-Targeted Extracellular Vesicles Potentiate Doxorubicin-Induced Apoptosis and Tumor Suppression in Colorectal Cancer.

Colorectal cancer (CRC), characterized by epidermal growth factor receptor (EGFR) overexpression, is often associated with poor prognosis and limited therapeutic response to conventional chemotherapy. In this study, we developed EGFR-targeted extracellular vesicles (EGFR-tEVs) by transiently engineering donor cells to display the GE11 peptide, aiming to enhance the precision of doxorubicin (Dox) delivery. The physicochemical properties of EGFR-tEVs were characterized using TEM, NTA, and Western blot. In vitro, EGFR-tEV-Dox exhibited increased cellular uptake in EGFR-overexpressing HCT-116 cells, leading to the activation of the p53-Bax-cleaved PARP1 apoptotic pathway. Notably, while Dox treatment induced p53 in normal colon fibroblasts (CCD18-Co), it did not trigger significant Bax activation or PARP1 cleavage, suggesting a preference for survival-related signaling in non-malignant cells. In a xenograft mouse model, EGFR-tEVs + Dox administration resulted in a 33.1% reduction in tumor volume and an 82.8% decrease in Ki-67 expression compared to the control group. These results indicate that transient receptor-mediated targeting enhances functional drug delivery to malignant tissues while minimizing pro-apoptotic induction in normal cells. Our findings suggest that EGFR-tEVs + Dox represents a balanced therapeutic strategy that improves antitumor efficacy with a favorable safety profile for EGFR-positive colorectal cancer.