Figure 5.
In vivo evidence for Leptin-mediated alterations of EMT markers and IL-8 expression levels. Groups of female nude mice (n = 5) were injected with 1×107 MCF-7 tumor cells in the mammary fat, and 15 d later, intratumor injection of PBS or leptin at 0.1 μg/g was performed biweekly until the 30th day, respectively. The mice were sacrificed. (A, B) Tumor volume and (B) primary weight of mice treated with PBS were significantly smaller than that of leptin injection (P < 0.001). (D) Survival time curve revealed that leptin reduced survival rate of tumor-bearing mice compared with group PBS (P < 0.001). (E) H&E staining demonstrated leptin promoted lung and liver metastasis of breast cancer xenografts. (F) Leptin increased expression of IL-8, Ki67 and Vimentin while decreased expression of E-cadherin evaluated by IHC.