Novel Peptide-Modified Zeolitic Imidazolate Framework-8 Nanoparticles with pH-Sensitive Release of Doxorubicin for Targeted Treatment of Colorectal Cancer

<b>Background</b>: Colorectal cancer (CRC) is one of the common malignant tumors. Chemotherapeutic agents represented by doxorubicin (DOX) are common adjuvant therapies for patients with advanced CRC. However, DOX suffers from dose-dependent cardiotoxicity and myelosuppression due to a lack of targeting and specificity, which severely limits its clinical application. <b>Methods</b>: Herein, we constructed a zeolitic imidazolate framework-8 (ZIF-8) modified by a novel peptide (LT peptide) to deliver the chemotherapeutic drug doxorubicin (DOX) for the targeted treatment of CRC. <b>Results</b>: In this study, LT-PEG@DOX@ZIF-8 nanoparticles were prepared by a simple method with suitable particle size and zeta potential, which were also capable of pH-responsive drug release. In vitro assays exhibited that LT-PEG@DOX@ZIF-8 nanoparticles were effectively taken up by C26 cells, significantly inhibited cell proliferation, and induced apoptosis. Furthermore, in mice models with colorectal tumors, LT-PEG@DOX@ZIF-8 nanoparticles also displayed specific tumor aggregation and exerted anti-tumor effects to prolong the survival of the mice. <b>Conclusions</b>: In conclusion, LT-PEG@DOX@ZIF-8 provides a promising strategy for the delivery of DOX to effectively treat CRC.