EGFR and triple-negative breast carcinoma: In triple-negative breast cancer MDA-MB-231 and MDA-MB-436 cells, knockdown of ER-α36 expression enhances EGFR protein degradation through the proteasome system while EGFR signaling pathway up-regulates the promoter activity of ER-α36 through an Ap1 binding site in the 5′ flanking sequence of ER-α36 gene [28].