Figure 8.

miR-718 mediates K1- and Nef-induced tumorigenesis in nude mice. (A) Inhibition of miR-718 abrogates the enhanced effect of Nef on K1-induced tumorigenesis. EA.hy926 cells transduced with K1, Nef or both were infected with control virus (pCDH) or miR-718 sponge for 72 h and further re-suspended in serum-free medium. As detailed in the ‘Materials and Methods’ section, the treated cells were injected (s.c.) into nude mice. The sizes of tumors from nude mice were determined by two-dimensional caliper measurements. Data represent mean ± SD, each group with five tumors (n = 5). Two independent experiments were performed and similar results were obtained. ** and *** indicate P < 0.01 and P < 0.001 by Student's t-test, respectively. (B) Tumor-bearing mice were killed at day 56 after injections, and tumors were removed and pictures were taken. (C) Inhibition of miR-718 abrogates the enhanced effect of Nef on K1-induced tumorigenesis. The tumors from nude mice treated as in (A) were removed and weighed. Scatter plots represent the weights of independent tumors from different groups. Data represent mean ± SD, each group with five tumors (n = 5). Two independent experiments were performed and similar results were obtained. (D) Inhibition of miR-718 increased total PTEN level and suppressed the enhanced phosphorylation of AKT and mTOR by K1 and Nef. The tumor tissues from nude mice treated as in (A) were removed, and the expression of total PTEN, phosphorylation levels of AKT and mTOR in tumor tissues were analyzed by Western blot. Numbers labeled under the bands were the relative intensities of the bands after calibration for loading with the house-keeping protein tubulin. The relative value of proteins in K1 + pCDH group was considered as ‘1’.