Figure 6. Liposomal delivery of anti-miR551b-3p reduces tumor burden and downregulates STAT3 in vivo.
A, HEYA8 cells (2.5 × 105 cells/animal) stably express luciferase reporter genes were injected into the peritoneal cavity of nude mice (n=10). Mice were treated with con. antimiR or anti-miR551b-3p encapsulated in DOPC nanoliposomes. Bioluminescence imaging was performed on day 28 and the images of five representative mice from each group is displayed. The color scale bars depict photon fluxes emitted from the tumor cells. B, Luminescence intensity was quantified (n=10) on the indicated days. Bars represent standard error (s.e.). Significance was determined by two-way Anova test. C–D, Tumor nodules were isolated on day 28. Numbers of abdominal tumors and total tumor weight were calculated. p values were determined by Student’s t-test. E–F, RNA was extracted from three representative tumor samples from each group. Relative expression of miR551b-3p and STAT3 was analyzed by qRT-PCR and normalized to U6 RNA or β-Actin respectively. p values were determined by Student’s t test. G, Tumor tissues from 5 separate tumors (A) were lysed and immunoblotting performed using the indicated antibodies. H–I, In vivo effects of anti-miR551b-3p treatment on tumor cell proliferation were determined by Ki67 immunohistochemistry (IHC). Ki67 positive cells were quantified in three different fields from the tumor tissues isolated from three mice from each group. p values were determined by Student’s t test. Scale bar represents 100 μm. J, Two-step model illustrates the process how STAT3 is regulated by miR551b-3p and the action of STAT3.