Background
CYR61(Cysteine-rich protein 61) is a member of CCN family, which is characterized primarily by its high cysteine content. CYR61 regulates diverse cellular events including cell proliferation, differentiation, angiogenesis, and extracellular matrix formation. CYR61 plays a role in the development or progression of various cancers, including breast, prostate, lung, and hepatocellular carcinoma. Notably, its role in promoting cancer progression appears to be context-dependent. For example, investigators have shown that overexpression of CYR61 was positively associated with invasiveness of breast cancer cell lines, whereas in primary prostate tumors, expression levels were inversely correlated with tumor aggressiveness.