Sulfated galactofucan from Sargassum thunbergii induces senescence in human lung cancer A549 cells

Lung Cancer

Bao Y, et al. Food Funct 2020.


Isolated compounds from Sargassum thunbergii (S. thunbergii) have shown to exhibit diverse biological activities, including anti-cancer activity. In this study, we examined the effect of sulfated galactofucan (SWZ-4-H), which was successfully isolated from S. thunbergii, and its underlying mechanism on human lung cancer (LC) A549 cell growth in vitro and in vivo. In vitro experiment indicated that SWZ-4-H decreased cell growth and number in a dose-dependent manner (P < 0.05 vs. control). Besides, cells treated with SWZ-4-H had irregular morphology, including increased cell volumes, and large nuclei, which suggested senescence-like changes. Moreover, SWZ-4-H increased senescence-related β-galactosidase (SA-β-Gal) staining in a dose-dependent manner; however, while lower (1 mg mL-1) concentration induced mainly senescence without causing cell death, higher dosage (3 mg mL-1) induced both senescence and cell death. The effect of SWZ-4-H was further confirmed by analyzing the expression of p53, p21, p16, and Rb (p-RB); SWZ-4-H significantly increased the expression of p53, p21, and p16 and decreased phosphorylated Rb (p-RB) in a dose-dependent manner. Moreover, in vivo experiment showed that SWZ-4-H significantly reduced the tumor volume without affecting the body weight. To sum up, our data indicated that SWZ-4-H could induce lung cancer senescence by regulating p53, p21, p16, and p-Rb, thus providing a novel perspective on anti-cancer mechanisms of SWZ-4-H in human lung cancer A549 cells.