tokens: Furthermore , deletion and mutation analyses of the VCAM - 1 promoter performed with chloramphenicol acetyltransferase constructs revealed that Tax was trans activating the VCAM - 1 promoter via two NF - kappaB sites present at bp - 72 and - 57 in the VCAM - 1 gene promoter , with both of them being required for the Tax - induced expression of this adhesion molecule .