Genus Vernonia (Asteraceae): A Promising Source of Antitumor Agents with Pharmacological Potentials

Antitumor research leads to the development of new molecules that act specifically in tumor cells by blocking or inhibiting their molecular targets. New therapeutic approaches for the screening of bioactive compounds present in medicinal plants have received increasing attention due to their chemopreventive and chemotherapeutic properties. In ethnomedicine, plants of the genus Vernonia (Asteraceae) are widely used and some have shown several and interesting biological activities, including anticancer. This present study aimed to document experimental evidence supporting the claimed ethnomedical uses of Vernonia species for the treatment of various types of cancer and also to confirm the anticancer potential of these plants. The compounds isolated from aqueous and alcoholic extracts, as well as fractions from different parts of Vernonia plants have acted as potential anticancer agents that inhibited the proliferation of various types of human cancer cell lines, including cervical cancer cells, melanoma cells, promyelocytic leucemia cells, breast adenocarcinoma cells, ovarian cancer, liver cancer cell, and human lung cancer cells. Studies have correlated the antitumor activity of Vernonia plants by inducing apoptosis and modulating mitochondrial signaling pathways controlled by NF-κB, Bcl-2 and p53, as well as inducing DNA damage and arresting the cell cycle at the S-phase checkpoint by oxidative stress. In conclusion, Vernonia species act as a promising source for drug development. However, further studies are needed to explore the exact mechanism of action, pharmacokinetics, chronic toxicological studies, safe dose consumption, and possible interactions with other herbs.