Isobaric tags for relative and absolute quantitation-based proteomics analysis of the effect of ginger oil on bisphenol A-induced breast cancer cell proliferation.

Several chemicals in the environment, particularly those with estrogenic activity and small amounts (micromolar or lower) of environmental estrogen can cause changes in cell function and interfere with endocrine functions of animals and humans. These compounds enter the human body and increase the load of estrogen in the body, leading to an increasing incidence of estrogen-related tumors in breast cancer, ovarian cancer and endometrial cancer. Previous studies have demonstrated that ginger can inhibit the expression of estrogen receptors, while the bioactive ingredients of ginger sig-nificantly inhibit proliferation and promote the apoptosis of breast cancer cells. In the present study, a quantitative proteomics technique based on relative and absolute quanti-tative isobaric labeling was used to determine the effect of ginger essential oil (GEO) and BPA combined treatment on the proteomic characteristics of MCF-7 cells. In total, 5,084 proteins were detected. Proteins that were upregulated >1.2-fold and downregu-lated by >0.8-fold were differentially expressed. Overall, 528 differentially expressed proteins were identified. Compared with the control group, MCF-7 cells treated with GEO, BPA and GEO-BPA resulted in 45 (14 up- and 31 downregulated), 481 (141 up- and 340 downregulated) and 34 (13 up- and 21 downregulated) differentially ex-pressed proteins, respectively. Compared with the BPA group, MCF- 7 cells treated with GEO-BPA resulted in 210 (117 up- and 93 downregulated) differentially expressed proteins, among the 210 differentially expressed proteins in the GEO-BPA group, 10 proteins were associated with oxidative phosphorylation pathways, while succinate dehydrogenase (ubiquinone) iron-sulfur subunit (SDHB), succinate dehydrogenase cytochrome b560 subunit, mitochondrial (SDHC), cytochrome oxidase subunit 2 and superoxide dismutase (Mn), mitochondrial (SOD2) expression was decreased with GEO-BPA combined treatment. Through the analysis of Gene Ontology and Kyoto Encyclopedia of Genes and Genomes, the cellular localization, functional annotation and biological pathways of differentially expressed proteins were ex-amined. The results indicated that GEO-BPA may act through the oxidative phosphory-lation pathway, decreased the expression of SDHB and SDHC, affected the tricarbox-ylic acid cycle and decreased the expression of SOD2. This may have led to oxidative stress and the death of breast cancer cells, and the SDH signaling pathway may be an important mediator of the inhibitory effects of GEO in MCF-7 breast cancer cells. GEO can inhibit the proliferation of breast cancer MCF-7 cells induced by BPA, and the underlying mechanism may be associated with oxidative phosphorylation. These results may aid the development of future treatment strategies for breast cancer caused by environmental estrogen exposure.