Low-density lipoprotein-decorated and Adriamycin-loaded silica nanoparticles for tumor-targeted chemotherapy of 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.