Anticancer potential, molecular mechanisms and toxicity of Euterpe oleracea extract (acai): A systematic review

Cancer is an increasingly frequent malignancy worldwide, and despite the advances in drug development, it is still necessary to develop new plant-derived medicines. Euterpe oleracea (acai) is abundant in South and Central America and has health benefits due to its high levels of phytochemicals, including lignans and polyphenols. The aim of this review was to systematically describe the safety and antitumor effects of acai in preclinical models using rodents to provide a more comprehensive assessment of acai for both therapeutic uses and the development of future clinical studies in cancer. Eligible studies were identified using four international databases (PubMed, Medline, Lilacs and SciELO) from their inception date through December 2017. The included studies were analyzed with methodological rigor (QATRS) to enable better quality control for these experimental studies. Sixty publications were identified in the databases, but only 9 articles were eligible: 6 evaluated the pharmacological effects of acai in animal models of cancer (1 model each of esophageal cancer, urothelial cancer, melanoma and Walker-256 tumor and 2 models of colon cancer), and 3 were toxicological assays using preclinical models with rodents. Overall, 747 animals were analyzed. On a QATRS score scale of 0-20, the quality of the studies ranged from 16 to 20 points. Pulp was the main fraction of acai administered, and an oral administration route was most common. The acai dosage administered by gavage ranged from 30 mg/ kg to 40,000 mg/kg, and acai fed in the diet accounted for 2.5% to 5% of the diet. The anticarcinogenic and chemopreventive activities of acai were observed in all experimental models of cancer and reduced the incidence, tumor cell proliferation, multiplicity and size of the tumors due to the antiinflammatory, antiproliferative and proapoptotic properties of acai. No genotoxic effects were observed after acai administration. The results of this review suggest that acai is safe and can be used as a chemoprotective agent against cancer development. acai therapy may be a novel strategy for treating cancer.