Apoptosis is managed by the Bcl 2 family of proteins and by caspases, which really is a family of cysteine proteases. Apoptosis induced by these substances may prevent carcinogenesis by removing damaged cells or inhibiting chemical catalogs cell development. Consequently, the induction of cell cycle arrest and apoptosis in cancer cells may be the basis of anticancer therapy. Several recent studies have suggested that fucoxanthin, a carotenoid found in seaweed, inhibits tumefaction cell growth by modulating the expression of cell cycle regulatory and apoptosis related genes. Nevertheless, information regarding its capability to cause cell cycle arrest and apoptosis in melanoma is missing. In this review, we aimed to research the molecular mechanisms of fucoxanthin induced cell cycle arrest and apoptosis in mouse melanoma cell line. Fucoxanthin was isolated from marine alga The details of the isolation have been published recently. Dulbeccos modified Eagles medium, fetal bovine serum, penicillin?streptomycin, and trypsin?ethylenediaminetetraacetic acid were purchased from Gibco BRL. RNase A, 3 2, 5 diphenyltetrazolium bromide, propidium iodide, dimethyl sulfoxide, and Hoechst 33342 were obtained Infectious causes of cancer from Sigma?Aldrich. Antibodies against phospho Rb, CDK4, cyclin D1 and D2, p15INK4B, p27Kip1, B cell lymphoma 2 associated X, B cell lymphoma additional large, cleaved caspase 3 and 9, cellular inhibitor of apoptosis 1 and 2, X linked inhibitor of apoptosis, and actin were purchased from Cell Signaling Technology. The other chemicals and reagents used were of analytical grade. B16F10 cells were grown in DMEM supplemented with 10 % heat inactivated FBS, penicillin, and streptomycin. Cultures were maintained at 37 C in a five hundred CO2 incubator. The cytotoxicity of fucoxanthin was based on a colorimetric MTT assay. B16F10 cells were seeded in a well plate at a of 2 104 cells/ml. After 16 h, the cells were incubated for 72 h at 37 C and treated with various concentrations of fucoxanthin. MTT stock solution was then added to each well to acquire a total reaction amount of 250 _l. After 4 h of incubation, the plate was centrifuged at 2000 rpm for 10 min, and the supernatant was aspirated. The formazan Dizocilpine dissolve solubility crystals in each well were dissolved in DMSO. The total amount of pink formazan was based on measuring the absorbance at 540 nm. The nuclear morphology of B16F10 cells was analyzed through the use of cell permeable DNA dyes Hoechst 33342 and PI. B16F10 cells were seeded in a well plate at a concentration of just one 105 cells/ml. After 16 h, the cells were treated with various levels of fucoxanthin and incubated for 24 h. Then, Hoechst 33342 and PI were added to the culture medium at a final concentration of 10 and 5 _g/ml, respectively, and the plate was incubated for another 10 min at 37 C.