Tax transactivates the MMP-9 promoter mainly through the NF-κB pathway.

(A) Jurkat cells were transfected with HTLV-I Tax (Tax WT), M22 Tax, or pHβAPr-1-neo vector and a CAT reporter construct containing the full-length MMP-9 promoter (−670 CAT). The results are expressed as fold induction relative to the basal level measured in cells transfected with the empty vector (pHβAPr-1-neo). (B) The indicated effector plasmids were cotransfected with −670 CAT. Open bar represents CAT activity of empty vector (pCMV4) without Tax. Solid bars represent CAT activity of IκBα and IκBβ mutants and kinase-deficient IKKα, IKKβ, and NIK mutants in the presence of Tax. The activities are given relative to the activity of empty vector (pCMV4) without Tax, which was defined as 1. The mean values and SDs represented were obtained from 3 experiments.