Fig. 7.
Repression of xenograft growth by miR-101. (a) In vivo tumor growth of miR-101–expressing cells. HCT116-miR-101 cells (3 × 106 cells/mouse) were implanted into the backs of nude mice (n = 14). After tumor size reached to 50–100 mm3, mice were separated into two groups (5–8 mice per group). The number of mice in each group is indicated at the top of the graph. Dox administration was started at the time point indicated by the arrow. Tumor size was measured twice per week. Data are shown as means ± SD of six tumor xenografts. Representative data of two independent experiments, carried out on the same number of mice, are indicated. **p < 0·01. (b) Representative image of in vivo tumors obtained from three to six mice on day 20. (c) Expression levels of miR-101 in the resultant tumors. Tumor tissues were removed from mice at day 20, and miR-101 levels were quantified by qRT-PCR. Number of samples: Dox (+), n = 5; Dox (−), n = 6. Data are expressed as the mean of triplicate reactions after normalization against the corresponding level of the RNU48 snRNA. (d) Protein levels of miR-101 targets in xenograft tumors. Data are representative of two independent experiments. (e) Sections were obtained from the resultant tumors on day 20 and analyzed by H&E staining (left two images) and p53 immunostaining (right two images). Scale bars, 50 μm. (f) Strongly p53-positive cells were counted using the Hybrid Cell Count software. Data are expressed as the percentage of total cells (2 × 104 cells in each sample) and are shown as means ± SD. (g) In vivo tumor growth of miR-101–expressing A549 cells. A549-miR-101 cells (3 × 106 cells/mouse) were implanted into the backs of nude mice (n = 18). After the size of xenograft tumors reached 50–100 mm3, mice were divided into two groups (6–8 mice in each group). The number of mice for each group is indicated at the top of the graph. Dox administration was started at the time point indicated by the arrow. Data are representative of two independent experiments, carried out on the same number of mice. * and ** indicate p < 0·05 and p < 0·01, respectively.