Chemical analysis and screening as anticancer agent of anthocyanin-rich extract from Uva Caimarona ( Pourouma cecropiifolia Mart.) fruit.

The anthocyanin-rich extract (ARE) of the fruit from Pourouma cecropiifolia , a tropical plant native to the Amazon region, showed moderate cytotoxicity toward different cancer cell lines when evaluated by MTT assays. This extract was fractionated using Sephadex LH-20 chromatography to obtain three fractions (F1-F3), the composition of which was analyzed by HPLC-PDA and LC-ESI/MS. F1 was composed primarily of the monomeric anthocyanins delphinidin-3-O-beta-glucopyranoside, cyanidin-3-O-beta-glucopyranoside, and cyanidin-3-O-(6''-malonyl)glucopyranoside. F2 contained the isomeric flavonols quercetin 3-O-alpha-rhamnopyranosyl-(1-->6)-beta-galactopyranoside and quercetin 3-O-alpha-rhamnopyranosyl-(1-->6)-beta-glucopyranoside, the structures of which were confirmed by (1)H and (13)C NMR. F3 contained polymeric pigments, which were analyzed using tandem ESI/MS with an ion trap-TOF. The structures of two proanthocyanidin and two flavanol-anthocyanin condensed pigments were suggested on the basis of their MS(n) fragmentation patterns. After cell viability assays were performed, only fraction F3 showed a cell growth-inhibitory effect similar to the one found for ARE. F3 significantly reduced the viability of HEp-2 larynx, MKN-45 gastric carcinoma, and MCF-7 breast cancer cells; in contrast, the pure compounds did not show promising cytotoxicity toward the cancer cells evaluated.

[Sensitivity profile of a panel of cell lines designed for the evaluation of in vitro cytotoxicity]. / Caracterización del perfil de sensibilidad de un panel de líneas celulares para valoración de citotoxicidad in vitro.

INTRODUCTION: Preliminary in vitro cytoxicity evaluations are determined in human tumor cell lines as a bioassay for the screening of potentially anticancer natural products. OBJECTIVE: To strengthen the available in vitro cytotoxicity evaluation models, the panel of cell lines was expanded, and the sensitivity profile of each cell line was evaluated for its response to selected antineoplasic drugs. MATERIALS AND METHODS: HeLa, MKN-45 and U-937 cell lines were added to the panel, and the sensitivity was determined for each of seven cell lines: HEp-2, HT-29, MCF-7, SiHa, MKN-45, HeLa and U-937. The effects of the antineoplasic drugs Doxorubicin HCl, Taxol, Cisplatin, Cyclophosphamide and Carmustin were examined, using the methyl thiazol tetrazolium (MTT) reduction assay. RESULTS: A differential sensitivity to the drugs Doxorubicin HCl, Taxol and Cisplatin was established among the cell lines by comparing the lethal concentration 50 (LC50) values. HEp-2 was the most sensitive cell line, whereas HeLa and U-937 were the most resistant. HEp-2 exhibited a biphasic response to Taxol treatment; this was related to the reported mechanism of action of this compound. CONCLUSION: Cyclophosphamide and Carmustin did not show activity under test conditions.

Caracterización del perfil de sensibilidad de un panel de líneas celulares para valoración de citotoxicidad in vitro / Sensitivity profile of a panel of cell lines designed for the evaluation of in vitro cytotoxicity

Introducción. La valoración de la citotoxicidad in vitro de líneas celulares derivadas de tumores humanos se emplea como bioensayo preliminar para el tamizaje de productos de origen natural con potencial actividad anticancerígena. Objetivo. Fortalecer el modelo de valoración de citotoxicidad in vitro disponible en el laboratorio, ampliando el panel de líneas celulares y caracterizando su perfil de sensibilidad a los fármacos antineoplásicos. Materiales y métodos. Se adicionaron al panel las líneas celulares HeLa, MKN-45 y U-937, y se evaluó la sensibilidad de las siete líneas celulares (HEp-2, HT-29, MCF-7, SiHa, MKN-45, HeLa y U-937) a los fármacos antineoplásicos doxorrubicina HCl, taxol, cisplatino, ciclofosfamida y carmustina, usados en la terapia antineoplásica. Para la valoración de la citotoxicidad se empleó el método de reducción del metil-tiazol-tetrazolio. Resultados. Al comparar las concentraciones letales 50 (CL50) calculadas, se evidenció una sensibilidad diferencial de las líneas celulares frente a doxorrubicina HCl, taxol y cisplatino, siendo HEp-2 la línea más sensible a todos los fármacos, en tanto que las HeLa y U-937 fueron las más resistentes. La respuesta de HEp-2 frente al taxol presentó un comportamiento bifásico, relacionado con su mecanismo de acción. Conclusión. En las condiciones empleadas no se observaron efectos frente a la ciclofosfamida y la carmustina.