Figure 3

LMP1-activates the mTOR signaling pathway through the phosphorylated AKT/mTOR/P70S6K/4EBP1 cascade in NPC cell lines. A. Western blot of stable transfected NPC cell line HONE1-LMP1 and LMP1 transiently transfected NPC cell line 6-10B. Increased expression of p-AKT, p-mTOR, p-P70S6K and p-4EBP1 was seen in both the HONE1-LMP1 and 6-10B-LMP1 cell lines. GAPDH acted as a loading control. B. Changes in gene expression measured by densitometry. LMP1 expression increased 2.9-fold in HONE1-LMP1 cells, and 2.8-fold in 6-10B-LMP1 cells compared to the vector control. Except for expression of mTOR in both cell lines, and AKT in 6-10B-LMP1 cell line, all genes increased in expression, with the ratio ranging from 1.2 to 1.9. Experiments were repeated three times independently, and mean and standard deviation are shown.