Upon cytokine treatment, human Peptidyl-prolyl cis-trans isomerase PIN1 binds to the phosphorylated Thr-254-Pro motif in human Nuclear factor NF-kappa-B p65 subunit (RELA) and inhibits p65 binding to I-kappa-B-alpha, resulting in increased nuclear accumulation and protein stability of p65 and enhanced NF-kappa-B activity