Anti-miR21 and resveratrol (RSV)-loaded mesoporous silica nanoparticles (MSNs) conjugated with hyaluronic acid (HA) were developed to enhance therapeutic efficacy in gastric carcinoma. The surface conjugation of HA, which acts as a targeting ligand to the overexpressed CD44 receptor on gastric cancer cells, was clearly identified by the presence of a greyish shell on the dark MSNs. Confocal laser-scanning microscopy and flow cytometry analysis showed higher cellular internalisation of HA/RSVmirNP compared to RSVmirNP. In vitro cytotoxicity and apoptosis assays confirmed the superior anticancer effect of the optimised formulation and synergistic effects of anti-miR21 and RSV in gastric cancer cells. Importantly, HA/RSVmirNP showed significant (p < .001) reductions in the tumour burden compared to the other group. Indeed, HA/RSVmirNP showed a threefold higher tumour regression effect compared to that of free RSV and a twofold tumour regression effect compared to that of RSVmirNP, indicating its anticancer efficacy. The percentage of TUNEL-positive cells was significantly higher in HA/RSVmirNP-treated cells compared to any other group, indicating that the mechanism underlying the superior anticancer efficacy of HA/RSVmirNP included apoptosis and cell necrosis. Thus, a combination of anti-miR21 and RSV in a targeted nanocarrier might be a promising drug delivery system for gastric cancer therapy.
Keywords: Gastric cancer; anti-miR21; cancer targeting; mesoporous silica nanoparticles; resveratrol.