EFEMP1, also known as fibulin-3, is a secreted glycoprotein in the fibulin family. It binds EGFR and activates downstream signaling (e.g., PI3K/AKT). Overexpressed in cancers like glioblastoma, it promotes malignancy and immunosuppression. As an emerging drug target, blocking antibodies and engineered protein variants (e.g., ZR30) are under development to inhibit tumor growth and angiogenesis, offering promising therapeutic potential.