Astaxanthin reduces MMP expressions, suppresses cancer cell migrations, and triggers apoptotic caspases of in vitro and in vivo models in melanoma

This study assessed the use of astaxanthin as an anticancer agent for increasing inhibition to melanoma cells (A375 and A2058). Wound healing and invasion assays presented that astaxanthin treatment reduced melanoma cell migration in a dose-dependent manner. The effects on melanoma cell migration were conferred via suppressed expressions of matrix metalloproteinases 1, 2 and 9. Dichlorofluorescein diacetate assay further showed that astaxanthin treatment reduced production of cellular reactive oxygen species. Cellular proliferation assay revealed potent dose-dependent inhibiting effects on melanoma cells. One-dimensional flow cytometric analysis demonstrated that astaxanthin induced cell cycle arrest in G1 phase. Mechanisms of apoptosis were verified by double fluorescence staining with annexin V-fluorescein isothiocyanate and propidium iodide. The antitumor effects of astaxanthin significantly decreased tumor size in a xenograft model. In summary, the experimental results showed that astaxanthin has potent in vivo and in vitro inhibiting effects on melanoma tumor growth for developing as chemotherapeutic agents.