EPLIN, Epithelial protein lost in neoplasm

We have identified a novel cytoskeletal protein, EPLIN (Epithelial Protein Lost In Neoplasm), that is preferentially er;pressed in human epithelial ce lls. Two EPLIN isoforms, a 600 amino acid EPLIN-alpha and a 759 amino acid EPLIN-beta, are detected in primary epithelial cells of oral mucosa, prosta te and mammary glands. The expression of EPLIN-alpha is either down-regulat ed or lost in the majority of oral cancer cell lines (8/8), prostate cancer cell lines (4/4) and xenograft tumors (3/3), and breast cancer cell lines (5/6), The amino acid sequence of EPLIN is characterized by the presence of a single centrally located LIM domain. Both EPLIN isoforms localize to fil amentous actin and suppress cell proliferation when overexpressed. These fi ndings indicate that the loss of EPLIN seen in cancer cells may play a role in cancer progression.