Fucoidan Extract Induces Apoptosis in MCF-7 Cells via a Mechanism Involving the ROS-Dependent JNK Activation and Mitochondria-Mediated Pathways
Fucoidan extract has been used in clinical trials in recent years. Nishimoto observed rapid increases of interleukin 12, interferon γ, and TNF-α values in the blood of a breast cancer patient (45-years-old female) after oral administration of 200 mL fucoidan extract solution (40 mg/kg/day) for 1.5 and 4 months . Two cervical cancer patients (a 49-year-old female and a 24-year-old female), a renal cancer patient (81-year-old male), and a liver cancer patient (74-year-old female) also experienced improvement in their symptoms after receiving fucoidan extract orally at 30–40 mg/kg/day . Since 2004, Takada  has performed a clinical trial in three patients (a 47-year-old female, a 78-year-old male, and an 84-year-old female) with hepatocellular carcinoma. The patients who received 180–400 mL of FE orally per day (30–80 mg/kg/day) showed overall decreases in their α-fetoprotein (AFP) and des-y-carboxyprothrombin (DCP) levels after several days' treatment. The patients experienced significant quality-of-life improvements during the initial 3–5 months of oral therapy and subsequent remission or disappearance of their cancers. Although there is no clearly evident theoretical mechanism to account for the potentially improved response and survival rates in carcinoma patients treated with FE, these findings suggest that FE is safe for cancer patients and has potential for use for cancer prevention and intervention in humans. Fucoidan extract of an average molecular weight of 28.8 kDa was detected without degradation in subjects' serum, plasma, and urine 6 h after oral administration . In fact, the average molecular weight of FE used in our study was about 500 Da, far lower than that of traditional fucoidan. Sulfated polysaccharides from the same family may exhibit different properties depending on their electrical charges, degrees of sulfation, and molecular weights , –. The low molecular weight of FE is expected to facilitate rapid absorption into blood vessels and effective action against cancers of various organs.