Mangoes (Mangifera indica) are an excellent source of lupeol, and a good source of beta-carotene and vitamin C. Mango peel is also a significant source of ellagic acid, ferulic acid, gallic acid, mangiferin, protocatechuic acid and quercetin. However, the peel also incorporates urushiol, which can cause allergic reactions.
Mangoes and their components have been shown to act as powerful antioxidants, have radioprotective properties, help prevent atherosclerosis, and improve glucose and lipid parameters in experimental mice fed a high-fat diet. Mango peel compounds have been reported to have antiproliferative and pro-apoptotic activities (which trigger programmed cell death) against human leukemia, as wells as human lung, colon, ovarian and prostate cancer cells.
Lupeol, a component of mango pulp (flesh), has been shown to inhibit proliferation and increase apoptosis of prostate, pancreatic and skin cancer cells in laboratory mice. One European population study found that consumption of mangoes was associated with lower risk of gallbladder cancer. A Mexican study found that consumption of mangoes was associated with lower risk of gastric cancer.

Breast cancer-related effects of eating mangoes

While mangoes contain compounds that suggest the fruit may have chemopreventive properties against breast cancer, no major population studies have been performed to evaluate this potential. One study of carcinogen-induced mammary tumor development in rats found that while long-term mango consumption increased rat plasma antioxidant capacity, it did not inhibit mammary tumor development.

Mango peel compounds inhibit breast cancer

Mango peel compounds have been demonstrated to have antiproliferative and pro-apoptotic activities against human hormone receptor positive ER+/PR+, hormone receptor negative (ER-/PR-), and HER2 overexpressing (HER2+) breast cancer cells. Gallic acid has been shown to increase the effectiveness of Taxol (paclitaxel) chemotherapy in ER+/PR+ breast cancer cells. Mangiferin has been shown to enhance the treatment effects of Adriamycin (doxorubicin) in ER+/PR+ breast cancer cells.
However, mangiferin and extracts rich in mangiferin have also been shown to increase endothelial cell migration, which could possibly assist angiogenesis (the formation of new blood vessels) in established tumors.

Lupeol is a promising anti-cancer compound

Lupeol has been found to inhibit the growth and proliferation of several cancer types, but the evidence concerning breast cancer is limited. Lupeol has been reported to resensitize drug-resistant cancer cells to chemotherapy. Lupeol has been shown to inhibit tumors growth in an animal model of prostate cancer, apparently by acting as an androgen receptor inhibitor.
Lupeol has been demonstrated to reduce the migration and invasion of triple negative (ER-/PR-/HER2-) breast cancer cells in a dose-dependent manner. Lupeol has also been shown to inhibit the proliferation of ER+/PR+ and HER2+ breast cancer cells.

Additional comments

Despite the similarity in the names, mangosteen (Garcinia mangostana), a Southeast Asian tropical fruit, is not related to mango.
Below are links to recent studies concerning this food and its components. For a more complete list of studies, please click on mango.