Breast Cancer Upregulating Genes in Stromal Cells by LINE-1 Hypermethylation and Micrometastatic Detection

UNLABELLED: Changes in the methylation level of genes containing LINE-1 alter host gene regulation. AIM: This study demonstrates that paracrine signaling of breast cancer influences the epigenetic regulation of stromal cells. METHODS: We proved in vitro and in vivo breast cancer promoted LINE-1 methylation exists exclusively in female stromal cells. RESULTS: Genes containing LINE-1 of breast cancer stromal cells were upregulated. Furthermore, one of the genes, MUC-1, was demonstrated to have expression in plasma cells from the lymph nodes of patients with lymph node metastasis or micrometastasis. CONCLUSION: Breast cancer sends a paracrine signal to stroma cells causing LINE-1 epigenetic regulation. Moreover, the regulated genes in stroma cells are potential biomarkers for detecting breast cancer micrometastasis.