Combined miR-181a-5p and Ag Nanoparticles are Effective Against Oral Cancer in a Mouse Model.

Abstract

Oral squamous cell carcinoma is the most common type of malignant tumor in the head and neck region. Despite advancements, metastasis and recurrence rates remain high, and patient survival has not significantly improved. Although miRNA therapies are promising for cancer gene therapy, their applications in treating oral cancer are limited. Targeted medication delivery systems based on nanotechnology offer an efficient way to enhance oral cancer treatment efficacy. We synthesized nanosilver (AgNPs) and loaded them with the tumor suppressor miR-181a-5p. In vitro experiments were conducted to investigate the inhibitory effects of AgNPs and their composites on the malignant behavior of oral cancer cell lines. The xenograft experiment was utilized to examine their effects on tumorigenesis and the potential molecular mechanisms involved. The nanosilver exhibited a spherical morphology with a size distribution ranging from 50 to 100 nm. They exhibited a distinct absorption peak at 330 nm and could be excited to emit green fluorescence. The biocompatible AgNPs effectively shielded miRNA from degradation by RNase and serum. The nanocomposites significantly inhibited the proliferation, invasion, migration, and colony formation of oral cancer cell lines. Notably, treatment with the nanocomposites resulted in substantial tumor growth suppression in the xenograft model. Mechanistically, these composites directly targeted BCL2 and exerted their antitumor effects by suppressing the β-catenin signaling pathway and other downstream genes without inducing acute toxicity. Collectively, the findings demonstrate that the miR-181a-5p/AgNPs combination significantly impedes the growth and progression of oral cancer both in vitro and in vivo, highlighting a pivotal role for the β-catenin signaling pathway. This multifaceted approach holds promise as a prospective therapeutic strategy for oral cancer management in the future.