Figure 7.

The Role of miR-1 in Tumorigenesis of Melanoma Stem Cells In Vivo

(A) Effects of miR-1 on solid tumor growth in mice. Melanoma stem cells overexpressing miR-1 or control cells were injected into nude mice. Two weeks later, the tumor volume in mice was measured every week. Each point represents the mean of five mice (*p < 0.1; **p < 0.01). (B) Evaluation of tumor size in miR-1-overexpressing mice. At 6 weeks after cell injection, the mice were sacrificed and the tumor volume was examined. (C) Western blot analysis of miR-1 targets in solid tumors of miR-1-overexpressing or control mice. Actin was used as a control. (D) Western blot analysis of LC3 and PINK1 proteins in solid tumors of miR-1-overexpressing or control mice. Actin was used as a control. (E) Immunohistochemical analysis of miR-1 targets mitophagy markers in solid tumors of miR-1-overexpressing or control mice. Brown represented Ki67, MINOS1, GPD2, LRPPRC, PINK1, or LC3 protein. Nuclei were stained with hematoxylin (blue). Scale bars, 50 μm. (F) The expression levels of miR-1 and its targets in melanoma and breast cancer tissues. Based on the GEO database, the expressions of miR-1 and its targets in the healthy and cancerous tissues of patients were evaluated. (G) Model for the miR-1-mediated mitophagy of cancer stem cells.