ST5, DENND2B, HTS1, Suppression of tumorigenicity 5 protein, DENN domain-containing protein 2B, HeLa tumor suppression 1

ST5 was identified by its ability to suppress the tumorigenicity of Hela cells in nude mice. The protein contains a C-terminal region that shares similarity with the Rab 3 family of small GTP binding proteins. This protein preferentially binds to the SH3 domain of c-Abl kinase, and acts as a regulator of MAPK1/ERK2 kinase, which may contribute to its ability to reduce the tumorigenic phenotype in cells.