CRIP2 is a putative transcription factor. It has a widespread tissue expression and is highly expressed in heart. CRIP2 contains two LIM zinc-binding domains. CRIP2 may participate in the differentiation of smooth muscle tissue. It also plays an important role in esophageal squamous cell carcinoma (ESCC) tumorigenesis. CRIP2 acts as a transcription repressor of the NF-κB-mediated proangiogenic cytokine expression and thus functionally inhibits tumor formation and angiogenesis. It interacts with the NF-κB/p65 to inhibit its DNA-binding ability to the promoter regions of the major proangiogenesis cytokines critical for tumor progression, including IL6, IL8, and VEGF. In conclusion, we provide compelling evidence that CRIP2 acts as a transcription repressor of the NF-κB-mediated proangiogenic cytokine expression and thus functionally inhibits tumor formation and angiogenesis.

> 95 % as determined by SDS-PAGE