The fibroblast activation protein alpha encoded by FAP is a homodimeric integral membrane gelatinase belonging to the serine protease family. It is selectively expressed in reactive stromal fibroblasts of epithelial cancers, granulation tissue of healing wounds, and malignant cells of bone and soft tissue sarcomas. Seprase is thought to be involved in the control of fibroblast growth or epithelial-mesenchymal interactions during development, tissue repair, and epithelial carcinogenesis. Alternatively spliced transcript variants encoding different isoforms have been found for FAP.

FAP; Seprase; 170 kDa melanoma membrane-bound gelatinase; Fibroblast activation protein alpha; Integral membrane serine protease