Family With Sequence Similarity 57, Member B (FAM57B)

FAM57B contains 1 TLC (TRAM/LAG1/CLN8) domain. The CT120B protein was predicted to have six transmembrane domains. The green fluorescent protein-tagged CT120B was localized on plasma membrane and in cytoplasm in SPC-A-1 cells. The expression of CT120B/A in normal lung tissue and in lung cancer cells was also examined. Results showed that the stable CT120B overexpression in SPC-A-1 cells resulted in a reduction of cell growth rate, and inhibited tumorigenecity and anchorage-independent growth in nude mice. The functions of CT120A and CT120B for cell growth appeared antagonistic. The delayed G₁/S phase transition might contribute to the inhibitory activities of CT120B on cell growth and that the deleted 32 amino acids missing in CT120B might be essential for the oncogenetic activities of CT120A.