FIG 6.
E6 and E7 expression by themselves sensitizes N/Tert-1 cells to estrogen. (A) N/Tert-1 (i), N/Tert-1+HPV16 (ii), N/Tert-1+E6 (iii), N/Tert-1+E7 (iv), and N/Tert-1+E6E7 (v) cells were seeded on day zero and grown in the presence or absence of estrogen. Cells were trypsinized and counted on daya 3 and 6, and cell counts are presented on a logarithmic scale. Statistical differences can be observed on both days 3 and day 6 in panel ii, but only on day 6 in panels iii to v. *, P < 0.05; **, P < 0.001. (B) Day 3 cell counts are compared as a percentage of control and normalized. Only N/Tert-1+HPV16 cells present a statistical difference at this time point. **, P < 0.001. (C) N/Tert-1+E6, N/Tert-1+E7, and N/Tert-1+E6E7 cells were analyzed for their RNA expression levels of E6 and E7 and compared to the loading control GAPDH. Data are presented as fold expression as calculated from ΔΔCT calculated from the comparison of levels observed in control cells and further compared to GAPDH levels. No statistical differences were found.