SNED1 (Sushi, nidogen and EGF-like domain-containing protein 1), also known as stromal nidogen extracellular matrix protein (Snep) and secreted protein SST-3, is an approximately 150 kDa protein (1). Mature mouse SNED1 contains 1379 aa that includes a Sushi/CCP (complement control protein) domain, an NIDO domain, 15 EGF-like domains, and 3 fibronectin type-III domains (1). Mouse SNED1 shares 84% and 96% aa sequence identity with human and rat SNED1, respectively. Alternative splicing generates an isoform lacking the Sushi/CCP domain, normally found in the center of the protein. SNED1 is mainly expressed in kidney stromal cells, but can be found in mesenchymal cells of other embryonic tissues, and within the nervous system (1,2). SNED1 has been found to have a role in tumor progression and metastasis. Studies show that SNED1 is up-regulated in highly metastatic mammary tumors while it is found to have relatively lower expression levels in poorly metastatic mammary tumors (3). SNED1 has also been shown to be up-regulated in pancreatic ductal adenocarcinoma cells which correlates with an increased chemoresistance (4). Additionally, SNED1 is found to be expressed specifically in stroma cells of the kidney and other organs in areas that undergo apoptosis during embryonic development making it important for kidney development (1).