Cancer is a complex disease, and some projections indicate that in 2030,
cancer mortality will reach approximately 11.4 million deaths worldwide. One
treatment for cancer is chemotherapy. However, cancer cells could present resistance to
the therapeutic compounds, and these compounds also have adverse effects. New drugs
with anticancer activity have been successfully found in plants. Essential oils (EOs) are
a mixture of over 100 volatile organic compounds abundant in aromatic plants. EOs are
mainly composed of compounds of low molecular weight, such as monoterpenes,
sesquiterpenes, and phenolic compounds. The chemical composition of EOs depends
mainly on the plant species, place of origin, and climatic conditions. Generally, the EO
density at room temperature is lower than that of water. They are brown, yellow, or
colorless, and they have a perceptible aroma. EOs have been used throughout history in
different areas, such as in foods, cosmetics, cleaning supplies, and traditional medicine
for the treatment of certain health problems. Monoterpenes, built from two isoprene
molecules, are hydrocarbon terpenes and oxygenated compounds (terpenoids), such as
alcohols, aldehydes, ketones, acids, and esters. Monoterpenes are one of the main
chemical constituents of EOs that have appeared in a large number of studies, and their
anticancer efficacy has been documented between 2015-2020. This review presents the
latest research progress in the use of EOs and monoterpenes as anticancer agents. The
115 EOs and 26 monoterpenes obtained from 36 different plant families included in
this review show that Asteraceae and Lamiaceae have been the most studied families
during this period.
Keywords: Antitumoral activity, Cytotoxic activity, Cancer, Cell lines, Essential
oils, Monoterpenes.