Inhibitory effects of preventive and curative orally administered spinach glycoglycerolipid fraction on the tumor growth of sarcoma and colon in mouse graft models

The glycoglycerolipid fraction from spinach was purified, and this fraction was used to clarify bioactive functions, such as inhibition of DNA polymerase activity and cancer cell growth. The effects of the spinach glycoglycerolipid fraction on preventive and curative antitumor activities, and acute toxicity were investigated. After oral administration of 20 mg/kg of the glycoglycerolipid fraction for 2 weeks as preliminary medication, colon tumor growth was delayed, and the protein expression level of proliferating cell nuclear antigen (PCNA) was decreased in tumor tissue. Five days after tumor cell implantation, oral administration of, not only 70 mg/kg of the glycoglycerolipid fraction, but also the γ-cyclodextrin (CD) glycoglycerolipid fraction complex, for 4 weeks, suppressed sarcoma formation with no adverse reactions in mice. In the acute toxicity test, 2000 mg/kg of orally administered glycoglycerolipid fraction did not show evident toxicity. Hence, these results suggest that the spinach glycoglycerolipid fraction is a safe and effective anticancer bioactive agent and/or food material.