Blood type B antigen modulates cell migration through regulating cdc42 expression and activity in HaCaT cells.

ABO blood group is determined by carbohydrate antigens, called ABH antigens. It has been known that the change of carbohydrate antigen expression, including ABH antigens, has correlation with the tumor metastasis and survival; however, the exact mechanism remains to be elucidated. ABH antigens are expressed not only in blood cells but also in several tissues. In epidermis, ABH antigen is expressed in the uppermost spinous and granular layer. We investigated the role of ABH antigens on the cell migration of HaCaT keratinocytes, which express B antigen. Knock-down of B antigen expression by small interference RNA of FUT1 inhibited HaCaT cell migration. At that time, we found that lamellipodia and actin fiber were also reduced by knock-down of B antigen expression. The transcription of cdc42, a kind of Rho GTPase which plays a key role in actin polymerization, was reduced by down-regulated B antigen expression. Furthermore, the reduced B antigen expression also inhibited the interaction of cdc42 and N-WASP. Collectively, our data provide a clue how ABH antigens regulate the cell migration mechanism.