Pomolic Acid: Cancer Molecular Targets, Plant Extraction Yields and Availability

Pomolic acid (3-beta,19alpha-Dihydroxy-urs-12-en-28-oic acid, PA) is a naturally occurring pentacyclic triterpenoid. Derived from the mevalonate pathway through cyclization of 2,3-oxidosqualene, it has been widely found in several plant species. In the mid-1960s, PA was identified as the genuine aglycone of triterpenoid saponins from Sanguisorba officinalis, and studies on its biological activities began in 1989. Since then, several pharmacological properties have been described for this compound, including antitumoral activity. PA induced cell death in tumors, such as lung, brain, breast, and sensitive and resistant leukemia. Additionally, PA modulates resistant proteins and events involved in metastasis. Even though PA constitutes an important candidate for new treatment against several cancers, its availability hampers the evolution of PA studies toward clinical evaluation. This review discusses the limitations of PA availability, the recent approaches to improve it, and other aspects of the antitumoral studies on PA activity.