To scrutinize the hypothesis deduced from the results of the negative correlation of the expression of huMETCAM/MUC18 with the three histological types of NPC tissue sections [11,33], we tested the effects of the over-expression of huMETCAM/MUC18 in NPC-TW01 cells on their in vitro behaviors and on in vivo tumorigenesis. Here, MCAM is linked to nasopharyngeal carcinoma.