Soy Foods Might Weaken the Sensitivity of Tamoxifen in Premenopausal Patients With Lumina A Subtype of Breast Cancer.

BACKGROUND: Based on estrogen active substances, many women consume soy foods in the belief that it could prevent breast cancer (BC). Women with different molecular subtypes would be likely to have diverse reactions to soy foods, especially those with the estrogen-receptor-positive (ER+ ) subtype. The aim of the current study is to identify the differentially expressed genes (DEGs) on soy foods in premenopausal patients with Lumina A subtype of BC (LABC) after soy food treatment, and to further investigate the critical molecule change.

MATERIALS AND METHODS: GSE58792 retrieved from Gene Expression Omnibus was analyzed to obtain DEGs using GEO2R. Gene Ontology and pathway enrichment analysis were performed using FunRich and GeneMINIA. Overall survival of critical genes was performed by the Kaplan-Meier plotter online tool.

RESULTS: A total of 108 DEGs were obtained from the dataset, among which 35 were up-regulated and 73 down-regulated. Soy foods significantly reduced the expression of TFF3, TFF1, GATA3, and ESR1, which were related to the activity of the ER-related pathway and the sensitivity of tamoxifen. Furthermore, the lower expressions of TOX3, FSIP1, ESR1, and CLGN were related to prolonged survival time of patients with BC. The most significant signaling pathways were epithelial-to-mesenchymal transition in up-regulated DEGs, mesenchymal-to-epithelial transition, and mammary gland alveolus development in down-regulated DEGs, which were all related to the development and prognosis of BC.

CONCLUSIONS: Soy foods could dramatically alter the ER-related gene profile in LABC. Particularly, down-regulated DEGs of TFF3, TFF1, GATA3, and ESR1 might weaken the sensitivity of tamoxifen and increase the efficacy of neoadjuvant chemotherapy in premenopausal patients with LABC.