Incorporation assays of natural anthraquinones in cancerous cells

FERNANDEZ, I.; COMINI, L.R.; NUÑEZ MONTOYA, S.C.; RUMIE VITTAR, B.; CABRERA, J.L.; RIVAROLA, V.

Palermo.

Congreso; XVII CONGRESO ITALO-LATINOAMERICANO DE ETNOMEDICINA. ?BERNARDINO D?UCRIA?; 2008

SILAE

We have demonstrated previously that four anthraquinones (AQs): rubiadin, soranjidiol, rubiadin 1-methyl ether and soranjidiol 1-methyl ether, isolated from stems and leaves of Heterophyllaea pustulata, exhibit photosensitizing properties by generation of superoxide anion radical and/or singlet molecular oxygen under irradiation conditions. In addition, we have established that these compounds show photodynamic activity against the human breast carcinoma cell line (MCF-7c3). Since photodynamic therapy is based on the combined action of a photosensitizer, molecular oxygen and light localized inside tumor cell, we studied the ability of these compounds to enter into cancerous cells, by using the cell line before mentioned. For that, AQs were dissolved in phosphate-buffered saline (PBS). The monolayer culture (105-106 cell/mL) was incubated with each AQ during 15 minutes at 37 °C. Then, the culture medium (extracellular fraction) was removed and the intracellular fraction was obtained by treating the cells with PBS/SDS (sodium dodecyl sulfate) 2% at -20 °C during 15 min. The control samples were processed without AQ and under the same working conditions. AQs were isolated from both intra and extracellular fractions by using CHCl3 in order to determinate the quali-quantitative composition of these fractions by HPLC. Whereas, identification was carried out by using standards compounds, quantification was achieved using the external calibration method. < In spite of the results showed that AQ were in the culture medium (extracellular fraction), these compounds were also accumulated inside cells. We determined that the four AQs entered into the cells between 10-20 %. Hence, we could get the conclusion that these percentages of AQs are sufficient to produce a significant photodynamic activity in vitro. p style="TEXT-ALIGN: justify; LINE-HEIGHT: 14pt; MARGIN: 0cm 0cm 0pt; mso-line-height-rule: exactly" class="MsoNormal">