Antitumor activity of tricin, a flavone isolated from leaves of Casearia arborea (Salicaceae)

Metastasis is one of the most important processes for the cancer progression, consisting to a set of events related to the tumor cell migration [1]. Considering that many chemotherapeutic agents used for treatment of cancer have side effects, active principles from plants played an important role in cancer chemotherapy [2]. Casearia Jaquin represents one of the largest genus in the Salicaceae family and accumulates bioactive clerodane type diterpenes [3]. C. arborea, was reported presence of casearborins A-E, from roots exhibiting cytotoxic activity against LOX and SF539 cell lines [4]. Aiming to isolate active compounds, MeOH extract from leaves of C. arborea was evaluated to cytotoxic activity against B16F10 and then fractioned to afford a flavone tricin. In order to evaluate the anti-proliferative activity of tricin, it was submitted to the clonogenic assays. Thus after 72 hour of incubation with tumor cells, was observed significant inhibition of colony formation, which may be related to a decreased proliferation profile of tumor cells. Also, was assessed the migration profile of murine melanoma cells after incubation of tricin and was observed that tricin significantly inhibited more than 60% the migration of melanoma cells. Thus for C. arborea the antitumor activity was due to the presence of a flavonoid that presents a more restricted occurrence in Casearia species. Additionally substances related to flavonoids have already been described with anti-migratory activity, and the description of tricin with this activity in the present work contributes to the development of prototypes that act as inhibitors of tumor cells.

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[4] Beutler J.A. et al, J. Nat. Prod. 2000, 63, 657.