FIGURE 7

FIGURE 7

SA inhibits Cav-1 expression and blocks late-phase autophagy and subsequent metastatic processes. (A) The expression levels of Cav-1 in MDA-MB-231 and BT-549 cells with different concentrations (0–200 μg/ml) or time intervals (24–72 h) of SA. All values represent the mean ± SD (n = 3, *p < 0.05, **p < 0.01). (B) The expression levels of Cav-1 in cells treated with SA (100 μg/ml) during starvation or hypoxic conditions. Values represent the mean ± SD (n = 3, *p < 0.05, **p < 0.01 vs. Ctrl, ##p < 0.01 vs. EBSS or hypoxia). (C) Cav-1, LC3-II, and p62 protein levels in MDA-MB-231 cells transfected with siCAV-1 with or without SA (100 μg/ml) during hypoxia for 48 h. Values represent the mean ± SD (n = 3, *p < 0.01 SA + empty vector group during hypoxia vs. SA + siCAV-1 group during hypoxia). (D) Cell counting assays and (E) wound healing assays as well as transwell invasion assays showed that SA suppressed breast-cancer growth and metastasis in a Cav-1-dependent manner under hypoxic stress. Values represent the mean ± SD (n = 3, *p < 0.05, *p < 0.01 SA + empty vector group during hypoxia vs. SA + CAV-1 group during hypoxia).