Inhibitors and dominant negative mutants targeting the EGFR and STAT3 pathways attenuated LMP1-augmented cyclin D1 promoter activity. (A-B) Stable expression of EGFR-DN and STAT3β inhibited the LMP1-increased activity of cyclin D1. The indicated NPC cell lines were transfected with a cyclin D1 promoter-reporter construct, a Renilla luciferase transfection control plasmid, and an EGFR-DN or STAT3-β expression plasmid. Twenty-four hrs. after transfection, the cells were treated with DNAzymes or a control oligo (2 μM) for 12 hrs. Cells were harvested at 36 hrs. after transfection and subjected to the luciferase assay. Firefly luciferase was measured and normalized to Renilla luciferase activity. The results were expressed as fold induction of the reporter activity in vector-transfected CNE1 cells, which was assigned a value of 1. (mean ± SD, n =3, * p