The actin filament-associated protein AFAP1 (AFAP-110) is an actin cross-linking protein first identified as a substrate of the viral oncogene v-Src. AFAP1 has a fundamental role in actin cytoskeleton arrangement. It contains a carboxyterminal actin-binding domain that directly binds to F-actin and serves as an adaptor protein in the regulation of SRC and PKC signal transduction by several functional domains, including 2 pleckstrin homology (PH) domains, a Src homology 3-binding (SH3-binding) motif, and several SH2-binding motifs. It is overexpressed in prostate carcinoma and contributes to tumor growth by regulating cell-matrix adhesions and migration in the cancer cells. AFAP1 represent a possible therapeutic target for controlling tumorigenesis and metastasis.