Follistatin-like protein 5 (FSTL5)

Follistatin-like protein 5 is an 847-amino acid, 93 kDa secreted glycoprotein encoded by the *FSTL5* gene, located at chromosome 4q32.2[1][3]. It shares structural features with other follistatin-like proteins, such as a Kazal-like domain, a follistatin-like module, EF-hand domains (calcium-binding), and an immunoglobulin-like domain[1][3][5]. FSTL5 has a highly restricted expression in the central nervous system (especially in olfactory regions, hippocampal CA3, and granular layer of the cerebellum in mice)[3]. Functionally, FSTL5 is implicated in regulation of caspase-dependent apoptosis, interacting with the BMP signaling pathway, and cell differentiation[1][5]. Its expression and/or dysregulation have been linked with cancer progression and prognosis, notably with a tumor-suppressive effect in hepatocellular carcinoma and a negative biomarker association in medulloblastoma and colorectal cancer[1]. Although its therapeutic targeting is still under investigation, it may serve as both a target and biomarker in some diseases, particularly cancer[1]. Key points: - It is a bona fide protein-coding gene and a member of the follistatin and SPARC families[1][3]. - FSTL5 is considered a putative therapeutic target largely in cancer, though detailed drug targeting information is unavailable[1]. - Its biological function is incompletely understood and is a subject of ongoing research[1][3].

Other names

FSTL5Follistatin-related protein 5Follistatin-like protein 5KIAA1263DKFZp566D234

No specific drugs directly targeting FSTL5 are described in available literature; mechanism inferred to be modulation of apoptosis pathways and BMP signaling.