Low-density lipoprotein-decorated and Adriamycin-loadedsilica nanoparticles for tumor-targeted chemotherapyof colorectal cancer

BACKGROUND: Chemotherapy for colorectal cancer remains an unsatisfactory method of treatment and requires the development of more advanced drug delivery systems (DDSs). Among inorganic materials, silica nanoparticles (SLNs) have been considered a suitable candidate to be developed as versatile carriers for drug delivery and imaging applications. Low-density lipoprotein (LDL) is a widespread material that is responsible for cholesterol transport in plasma. The concept of employing LDL-modified nanoparticles for tumor-targeted drug delivery has been widely adopted. OBJECTIVES: The objective of this study was to develop and test a new DDS for effective chemotherapy of colorectal cancer. MATERIAL AND METHODS: We successfully developed an Adriamycin (Adr)-loaded DDS based on LDL-modified SLNs (LDL/SLN/Adr). The tumor-homing property of LDL and the drug-loading capability of SLNs were combined to prepare LDL/SLN/Adr that can specifically deliver Adr to the cancer site to achieve effective chemotherapy of HT-29 colorectal cancer. RESULTS: In vitro analysis showed that LDL/SLN/Adr consisted of nano-sized particles and was capable of targeting the low-density lipoprotein receptors (LDLR) which were overexpressed in many cancer cell lines. As a result, LDL/SLN/Adr exerted better cytotoxicity than unmodified SLNs and free drugs. In vivo imaging and anticancer assays also confirmed the preferable tumor-homing and enhanced anticancer effect of LDL/SLN/Adr. CONCLUSIONS: LDL/SLN/Adr might be a promising DDS for effective chemotherapy of colorectal cancer.