Enhancing targeted cancer therapy through multiple drug delivery by silk peptide nanoparticles

Targeted therapy drugs exert an essential role in precision therapy in cancer treatments. However, their therapeutic efficiency is greatly limited by the poor water solubility and low bioavailability. Herein, by using an epidermal growth factor receptor (EGFR) targeted drug, erlotinib (ERL), as a representative of targeted therapy drugs, we demonstrate silk peptide (SP) extracted from silkworm cocoons can be used as a drug carrier to co‐load curcumin (CUR) and ERL to achieve dramatically improved antitumor therapeutic efficiency. The dual‐drug loaded nanoparticles (CUR/ERL@SP) with a mean size within 150 nm show significantly enhanced cell internalization, and thus induce more effective inhibition of cancer cell growth. As compared with free drugs, CUR/ERL@SP can more efficiently downregulate the expression of EGFR and other proteins promoting tumor invasion, immunosuppression and cell fusion in EGFR mutant PC‐9 lung cancer cells. The evaluation by using the circulating malignant cells (CMCs) from a lung cancer patient further confirms that CUR/ERL@SP can more effectively inhibit EGFR expression. This study provides a convenient strategy to enhance the therapeutic efficacy of targeted therapy drugs and a facile ex vivo method for evaluating treatment outcomes in personalized therapy.