Tat augments vIL-6-induced phosphorylation of PTEN, PI3K, AKT, and GSK-3β both <i>in vitro</i> and <i>in vivo</i>.

<p>(<b>A</b>) Effects of Tat on vIL-6 promoter activities in 293T cells. Cells were transfected with RTA expression plasmid (<b>With RTA</b>) or its control vector (<b>Without RTA</b>) and subsequently cotransfected with the firefly luciferase reporter construct pvIL-6-Luc (0.4 mg) and a Renilla luciferase construct pRL-TK (0.02 mg) following infection with Tat or Mock. Luciferase activities were measured, normalized to inner control, and presented as fold increase (n-fold). All data points were the averages of three independent experiments performed in triplicate. (<b>B</b>) Phosphorylation levels of PTEN, PI3K, AKT, and GSK-3β were analyzed by Western blot in 4E3 and T/V cells transduced by MOI 10 of Tat or Mock. Both 4E3 and T/V cells were starved with serum-free medium for 24 hours and followed by Tat or Mock transduction for 24 hours. The relative level of phosphorylation protein was determined by quantitative densitometry after normalized to corresponding non-phosphorylation protein. The relative level of phosphorylation protein in T/V+Mock group was considered to be 1 for comparison. (<b>C</b>) Phosphorylation AKT and GSK-3β in tumor tissues from 4E3 and T/V cells on the CAM were analyzed by Western blot as above.