Lupeol synergizes with doxorubicin to induce anti-proliferative and apoptotic effects on breast cancer cells.

Purpose: Anti-cancer and anti-migration effects of lupeol as a biological pentacyclic triterpenoid were investigated individually and in combination with Doxorubicin (DOX) on MCF-7 and MDA-MB-231 breast cancer cells and human foreskin fibroblasts.

Methods: To uncover the anticancer effect of lupeol and the impact of its combination with DOX, cell viability and scratch assays and dual acridine-orange apoptotic staining were performed. Moreover, the expression of proapoptotic caspase-3 and metastasis-related MMP-9 at the mRNA and protein levels was analyzed using qPCR and western blot techniques.

Results: Lupeol synergistically increased the anti-proliferative effect of DOX with IC50 values of 42.55, 62.24 and 65.9 μM on MCF-7, MDA-MB-231 and HFF cells, respectively. Lupeol reduced the cell migration and lowered the DOX-induced cell migration, significantly (p < 0.05). The number of apoptotic cells elevated significantly (p < 0.05) when cancer cells were treated with the combination of lupeol and DOX. Lupeol individually and in combination with DOX up-regulated the expression of caspase-3. The proposed combination therapy synergized (3-4 fold) the down-regulation of MMP-9 expression in MCF-7 and MDA-MB-231 cells.

Conclusion: Our results indicate that lupeol could be considered as an anticancer agent and anticancer adjuvant in breast cancer-therapy. The anticancer properties of lupeol attribute to its antiproliferative, antimigrative and apoptotic effects.