MiRNA-204-5p and oxaliplatin-loaded silica nanoparticles for enhanced tumor suppression effect in CD44-overexpressed colon adenocarcinoma.

Main purpose of present study was to enhance the therapeutic efficacy in the treatment of colon adenocarcinoma by combining the benefits of chemotherapy and gene therapy. In this study, we have successfully formulated oxaliplatin (OXL) and miRNA-204-5p loaded polyethyleneimine (PEI)/hyaluronic acid (HA)-assembled mesoporous silica nanoparticles (OXmi-HSMN). Our study, for the first time, proved that miRNA-204-5p can generate a synergistic anticancer effect with OXL with HMSN, and thus improve the effects of therapeutic efficacy in colon cancers. In vitro targeting studies showed that OXmi-HSMN exhibited higher uptake efficiency in CD44 receptor over-expressed HT-29 cells via CD44 receptor-mediated endocytosis. OXmi-HMSN exhibited a higher cell cytotoxicity compared to any other formulations indicating that internalization via CD44 receptor-mediated endocytosis increased the anticancer effect. The OXmi-HMSN showed significantly higher pre-apoptotic cells (43.9%) with significant apoptosis fractions (upper right quadrant - 20%) indicating the superior anticancer efficacy in terms of apoptosis inducing potentials. Importantly, OXmi-HMSN caused conspicuous inhibition of tumor growth and was significantly greater than that of either OXL or OXL-MSN (p < 0.0001). OXmi-HMSN showed 30% of TUNEL positive cells compared to 8% TUNEL positive cells for free OXL and 6% for free miRNA-204-5p treated group indicating the wide spread apoptosis of cells throughout the tissue section. Current study provides a delivery platform for dual therapeutics for enhanced therapeutic efficacy in the management of colon cancer.