This may be related with changes in several metabolic pathways, namely hydrocarbon metabolism,28 fatty acid β-oxidation,29 intensification of cellular membrane synthesis30 and alterations in the activity of some important enzymes, namely CYP 45031 and alcohol dehydrogenases.28 Several studies have demonstrated the intracellularly increased concentrations of reactive oxygen species (ROS) in cancer cells,32,33 which are capable of causing the oxidation of biologically crucial molecules such as DNA, RNA, proteins and lipids. This evidence concerns the gene AKR1A1 and cancer.