ZSTK474 is primarily used in biomedical research as a potent and selective inhibitor of phosphoinositide 3-kinase (PI3K). It targets all class I PI3K isoforms (α, β, γ, δ) and shows strong activity in blocking the PI3K/Akt/mTOR signaling pathway, which is frequently dysregulated in various cancers. Due to this property, ZSTK474 is widely employed in preclinical studies to investigate tumor growth suppression and apoptosis induction in cancer cell lines. It has demonstrated antiproliferative effects in models of leukemia, breast cancer, and glioblastoma, among others. Researchers also use ZSTK474 to study autophagy and cell cycle arrest mechanisms linked to PI3K inhibition. Its ability to cross the blood-brain barrier makes it particularly valuable in studies targeting central nervous system malignancies. In addition to oncology, ZSTK474 is explored in immunology and inflammatory diseases due to PI3K's role in immune cell activation. However, its use remains confined to laboratory and experimental settings, with no current approval for clinical therapy.