LAUSR

Purpose: To investigate Euphorbia tirucalli extract for probable geographic variations in its antiproliferative activity. Methods: The aerial parts of E. tirucalli were collected in the Brazilian states of Mato Grosso, Rio de Janeiro, Para, Minas Gerais and Santa Catarina. The 70 % ethanol extract was obtained according to the procedure described in Brazilian Homeopathic Pharmacopeia. The antiproliferative activity of extracts, in concentrations of 62, 125, 250, and 500 μg mL -1 , was tested against leukemia (HL-60), lymphoma (Daudi) and melanoma (B16F10) cell lines using methyl thiazol tetrazolium assay (MTT). Phytochemical analysis were carried out using High-performance liquid chromatography-diode array (HPLC-UV-DAD) and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI(-) FT-ICR MS) assays. Results: There was significant regional variability in the cytotoxicity of E. tirucalli extracts in a dosedependent manner. The extracts had similar activity towards leukemia cell line HL-60, decreasing cell viability to about 60 – 70 %. The extract showed the presence of ellagitannins, flavonoids, veracylglucan, and acid triterpenes as the major compounds. Conclusion: While the results support the ethnopharmacological use of E. tirucalli throughout Brazil, regional quantitative differences found in some classes of secondary metabolites may explain the variations observed in antitumor activity. Keywords: Aveloz, Cancer, Cytotoxicity, Antiproliferative, Ethnopharmacological, Traditional medicine