SPOCK1: a multi-domain proteoglycan at the crossroads of extracellular matrix remodeling and cancer development.

The SPARC/osteonectin, CWCV and Kazal-like domains proteoglycan 1 (SPOCK1) is a highly conserved, multi-domain proteoglycan that regulates the dynamic equilibrium of extracellular matrix (ECM). Besides, SPOCK1 is one of the key regulatory genes in the tumor ECM dynamic homeostasis process, which activates many molecular signaling pathways (such as EMT process, Wnt/β-catenin, PI3K/Akt, and mTOR/S6K signaling pathways). This activation leads to ECM remodeling and promotes cell proliferation and invasion, but inhibits cell apoptosis. Whereas there is immense information about SPOCK1's roles in different biological settings, there is need for further studies that interrogate this protein as a potential therapeutic target in cancer.