Palm Oil Tocotrienols in Cancer Chemoprevention and Treatment

Abstract

Cancer remains a worrying cause of fatality worldwide despite the advancement in medicine. Among the dietary phytonutrients, tocotrienols have been extensively studied for their bioactivity against cancer. Palm oil is a rich source of tocotrienols. The most common formulation of tocotrienols is the tocotrienol-rich fraction of palm oil (TRF). The anticancer activities of tocotrienols were once presumed due to their antioxidant and free radical scavenging properties. However, recent evidence suggested that tocotrienols are capable of demonstrating cancer-fighting properties through their influence in various signalling pathways. The selectivity of tocotrienols in killing cancer cells without affecting normal cells is indicative of their potential role in cancer treatment and prevention. Tocotrienols had proven to be particularly effective in the chemoprevention and treatment of breast, colorectal, pancreatic, prostate and liver cancers in many in vitro and in vivo animal experiments. However, the efficacy of tocotrienols in the management of human cancers are still questionable due to their poor bioavailability and lack of well-designed clinical trials. Nevertheless, due to their superb safety profiles, palm oil tocotrienols are still considered ideal candidates for future large scale clinical trials to prove their efficacy to treat or prevent cancers in humans.

Effect of Administration of an Equal Dose of Selected Dietary Chemicals on Nrf2 Nuclear Translocation in the Mouse Liver

“…Free radicals cause damage when they react with other molecules to find electrons to pair with their unpaired electrons. The other molecules then lost their electrons, causing them to become free radicals themselves, thus creating a chemical chain reaction of free radical production [ 1 ]. Oxidative stress is a condition that occurs when there is an imbalance between the production and accumulation of free radicals (reactive oxygen species) in the living system and the ability of the living system to detoxify these reactive products [ 2 ].…”

“…The free radical chain reaction may cause damage to cellular homeostasis due to its potential in causing alterations in the lipid, protein, and DNA structure. The damaged molecules may initiate mutation and growth of tumours [ 1 ]. Reactive oxygen species (ROS) play an essential role in cell signaling and homeostasis.…”

“…Reactive oxygen species (ROS) play an essential role in cell signaling and homeostasis. However, high levels of ROS are responsible for various medical conditions, including ageing, cancer, inflammation, and chronic illnesses [ 1 ]. Therefore, exogenous antioxidants from the chemicals in foods have been used to prevent or repair the oxidative damage caused by ROS [ 3 ].…”

Dietary Vitamin E Isoforms Intake: Development of a New Tool to Assess Tocopherols and Tocotrienols Intake in Adults

“…γ-tocopherol shows higher activity in capturing reactive oxygen and nitrogen species than α-tocopherol, and its concentration in the blood may be related to a lower risk of cancer and cardiovascular diseases [19]. Research on tocotrienols is expanding worldwide due to their interesting biological properties that tocopherols do not have, including neuroprotective, radioprotective, anticancer, anti-inflammatory, and lipid-lowering properties [20]. Tocotrienols are also credited with angiogenic effects and participation in the regulation of the activity of enzymes and transcription pathways, which may be reflected in the prevention of cancer [21].…”

“…The main rich, natural sources of tocotrienols are palm oil, rice bran, wheat germ oil, coconut oil, and annatto seeds. An extract from the annatto seeds of the achiote tree (Bixa orellana L.) consists of 90% δ-tocotrienol and 10% γ-tocotrienol; palm oil, extracted from the reddish pulp of the fruits of the palm tree (Elaeis guineensis), consists mainly of 46% γ-tocotrienol and 22% α-tocotrienol [20,27,28].…”