Gami-soyosan is a medicinal herbal formulation prescribed for the treatment of menopausal symptoms, including hot flashes and osteoporosis. Gami-soyosan is also used to treat similar symptoms experienced by patients with breast cancer. The incidence of breast cancer in women receiving hormone replacement therapy is a big burden. However, little is known about the components and their mechanism of action that exhibit these beneficial effects of Gami-soyosan. The aim of this study was to simultaneously analyze compounds of Gami-soyosan, and determine their cytotoxic effects on estrogen receptor (ER)-positive MCF-7 human breast adenocarcinoma cells. We established a simultaneous analysis method of 18 compounds contained in Gami-soyosan and found that, among the various compounds in Gami-soyosan, gallic acid (1), decursin (17), and decursinol angelate (18) suppressed the viability of MCF-7 cells. Gallic acid (1), decursin (17), and decursinol angelate (18) induced apoptotic cell death and significantly increased poly (ADP-ribose) polymerase (PARP) cleavage and the Bcl-2-associated X protein/ B-cell lymphoma 2 (Bax/Bcl-2) ratio. Decursin (17) increased the expression of cleaved caspases-8, -9, -7, and -3. Decursinol angelate (18) increased the expression of cleaved caspase-8 and -7. These three components altered the different apoptosis signal pathways. Collectively, gallic acid (1), decursin (17), and decursinol angelate (18) may be used to inhibit cell proliferation synergistically in patients with ER-positive breast cancer.
Keywords: Gami-soyosan; MCF-7; apoptosis; breast cancer; decursin; decursinol angelate; gallic acid.