RESUMO
Very strong antiproliferative action of V. diospyroides type SS fruit extracts (IC50 range of 1.60-17.45 µg/mL) in MDA-MB-468 cell-line was observed in an MTT assay. After dosing of an extract concentration at half IC50 to cell line for 24 to 72 hours, treated cells were subjected to Annexin V-FITC/PI binding assay, followed by FACS and western blot analyses. Significant apoptotic death was observed with all extract treatments and both exposure times. Dosing with acetone extract of pericarp and cotyledon induced the highest apoptotic populations (33 and 32%, resp.), with the lowest populations of viable cells (65 and 67%, resp.). During 24 to 72 hours of dosing with methanolic extract of pericarp, the populations of viable and early apoptotic cells decreased significantly from 72.40 to 71.32% and from 12.00 to 6.36%, respectively, while the late apoptotic and nonviable cell populations continuously increased from 15.30 to 19.18% and from 0.30 to 3.14%, respectively. The expression of Bax increased within 12-48 hours of dosing, confirming apoptosis induced by time-dependent responses. The mutant p53 of MDA-MB-468 cells was expressed. Our results indicate that apoptosis and time-dependent therapeutic actions contribute to the cytotoxic effects of V. diospyroides type SS fruit on MDA-MB-468 cell.