ERBB2 and breast carcinoma: To ascertain if the novel engineered destabilized 3’UTR of ERBB2 will successfully target ERBB2 in trastuzumab-resistant breast cancer cells and control its aggressiveness, we experimented with the BT474 clone 5 (Reuter and Matthews, 2010; Torabi et al 2021) The ERBB2+ trastuzumab-resistant breast cancer cell line was developed by prolonged exposure to trastuzumab.