Considering that ID3 expression, which is a target gene of both Smad1/5/9 and p38, was increased by CCN6 combined with BMP2, and that production of CCN6 and BMP2 increased in the cells before EMT, it is suggested that CCN6 combined with BMP2 suppresses EMT of oral cancer cells in primary lesions. This evidence concerns the gene SMAD1 and lip and oral cavity carcinoma.