Plant derived and dietary phenolic antioxidants: Anticancer properties

•Most antioxidant phenolics exhibit anti-proliferative activity in cancer cells.•Extracts with higher phenolic content usually exhibit higher cytotoxic activity.•The correlation between antioxidant and cytotoxic activities is not always clear.•Brain, larynx, ovarian, pancreas, pleura and retina cancer cells are few studied.•Few studies of structure-anticancer activity relationships on phenolics are reported. In this paper, a review of the literature on the phenolic compounds with anticancer activity published between 2008 and 2012 is presented. In this overview only phenolic antioxidant compounds that display significant anticancer activity have been described. In the first part of this review, the oxidative and nitrosative stress relation with cancer are described. In the second part, the plant-derived food extracts, containing identified phenolic antioxidants, the phenolic antioxidants isolated from plants and plant-derived food or commercially available and the synthetic ones, along with the type of cancer and cells where they exert anticancer activity, are described and summarized in tables. The principal mechanisms for their anti-proliferative effects were also described. Finally, a critical analysis of the studies and directions for future research are included in the conclusion.