Complement C1q-like protein 4 (C1QL4)

Complement C1q-like protein 4 (**C1QL4**) is a secreted member of the C1q/TNF superfamily, structurally related to complement C1q and adiponectin family proteins. It is encoded by the C1QTNF11 gene and is also known as CTRP11. C1QL4 contains a characteristic C1q domain forming trimers, involved in protein-protein interactions and signaling. Functionally, C1QL4 binds to cell-surface receptors such as BAI3 (brain-specific angiogenesis inhibitor 3), regulating cell differentiation processes like myoblast fusion by acting as a negative regulator[2]. In cancer biology, C1QL4 promotes breast cancer cell stemness and drives epithelial-mesenchymal transition (EMT) through modulation of the PI3K/AKT/NF-κB signaling axis, correlating with poor prognosis and increased metastatic potential in breast cancer[4]. While detailed pharmacological targeting has not been described, its involvement in key regulatory cell pathways positions C1QL4 as a candidate therapeutic target in oncology and regenerative medicine[4][2][3].

Other names

C1QL4Complement C1q-like protein 4CTRP11C1q/TNF-related protein 11C1QTNF11Complement component 1, q subcomponent-like 4

Not established for drugs, but C1QL4 acts as a ligand for cell-surface receptors like BAI3, modulating downstream signaling pathways involved in cancer and tissue differentiation[2][4].