Apoptosis induction of the rosmarinic acid-loaded mesoporous organosilica nanoparticles on gastric cancer cells

Introduction: Rosmarinic acid has anticancer properties because it inhibits cell growth and induces apoptosis. However, its stability is significantly diminished in the acidic environment of digestive system. Although encapsulation of rosmarinic acid with nanoscale materials is required to increase its bioavailability, the anticancer activity must be maintained. We have previously synthesized a new form of organosilica nanoparticle that could efficiently load rosmarinic acid in its pores, called as RA@SiNPs. These compounds were hazardous to some cancer cells, but the exact mechanism of cell death remained unclear. This study sought to determine the ability of RA@SiNPs to cause apoptosis in the AGS human gastric cancer cells. Methods: Cells were incubated with various concentrations of nanoparticles for 24 hours. Cells were analyzed after another 48 hours. Cytotoxicity was assessed using Cell Counting Kit-8 test. Cell apoptosis was determined by flow cytometry, intracellular Caspase-3 activity and DNA apoptosis ladder analyses. Abnormal cell morphologies were stained and visualized using optical microscopes. Results: Approximately 54.31±9.16% of AGS cells survived after incubation with 240 μg/mL of RA@SiNPs. The cell ratios in the early and late stages of apoptosis were 10.50±2.83% and 32.50±2.40%, respectively. The necrosis ratio was relatively low. RA@SiNPs-treated cells exhibited Caspase-3 activity, DNA damage and apoptotic cell morphological abnormalities. Conclusions: This study determined that the RA@SiNPs nanomaterial significantly reduced the viability of gastric AGS cells via apoptosis. Using safe drug delivery materials like RA@SiNPs can ensure the therapeutic effect of the drug in patients without causing inflammation.