The differential expression of microRNAs, such as miR-21, miR-25, miR-146, and miR-9, significantly influences key pathways like TGF-β/Smad, PI3K/AKT, and VEGF/VEGFR2, thereby affecting endothelial cell function, angiogenesis, and tumor progression. The gene discussed is VEGFA; the disease is neoplasm.