Antiproliferative Effect of Urera baccifera Leaves Against Ovarian Carcinoma Cell Line (OVCAR-3)

Abstract Natural products, especially phytochemicals, have been extensively studies and have exhibited important antiproliferative effects. The American native species Urera baccifera (L.) Gaudich. ex Wedd. (Urticaceae) is widely distributed in Brazil, where it is known as urtiga-vermelha or urtigão. The leaves are popularly used as anti-inflammatory, antirheumatic and in the treatment of gastric disorders. However, the antiproliferative potential of this plant against human tumor cells remain to be elucidated. In this study, we evaluated the antiproliferative effects of U. baccifera leaves extracts and fractions against a panel of human tumor cell lines in vitro besides a chemical evaluation of the most active sample by mass spectrometry (ESI-IT-MSn). The hydroalcoholic extract was inactive while dichloromethane extract showed moderate cytostatic activity against ovarian carcinoma cell line (OVCAR-3, GI50 = 1.5 μg/mL). More, the ethyl acetate and n-butanol fractions did not show important activity against tumour cell while the dichloromethane and hexane fractions showed moderate cytostatic activity against ovarian tumor cell line (OVCAR-3, GI50 = 12.7 and 9.4 μg/mL, respectively). Finally, the chemical profile evaluated by mass spectrometry (ESI-IT-MSn) allowed the detection of flavonoids in the HEU and hydroxylated fatty acid in DEU that can explain partially the biological effects observed. This is the first report of the antiproliferative effects of U. baccifera, and DEU has shown potential as a promising source of bioactive compounds.

Antiproliferative potential of solidagenone isolated of Solidago chilensis

ABSTRACT Plants are considered among the main sources of biologically active chemicals. The species Solidago chilensis Meyen, Asteraceae, is native to the southern parts of South America, where the aerial parts of the plant are commonly used for the treatment of inflammatory conditions. However, the effects of S. chilensis on human cancer cells remain to be elucidated. In this study, we evaluated the antiproliferative effects of the hydroalcoholic and dichloromethane extracts of S. chilensis, as well as their chemical constituents quercitrin and solidagenone against the five human tumor cell lines in vitro. The dichloromethane extract showed a promisor antiproliferative effects in vitro, especially against glioma cell line. Besides, the hydroalcoholic extract and quercitrin were inactive. The diterpene solidagenone showed highly potent antiproliferative effects against breast (MCF-7), kidney (786-0), and prostate cancer (PC-3) cells (total growth inhibition: TGI < 6.25 µg/ml). Solidagenone meets the theoretical physico-chemical criteria for bioavailability of drugs, according to the "Rule of Five" and, by theorical studies, the observed biological effects were probably related to the interaction of the molecule with nuclear receptors and as an enzymatic inhibitor. This study contributes to chemical study and to the identification of antiproliferative molecules in S. chilensis.