ERBB2 and breast carcinoma: For example, in clinical tissue samples of breast cancer, high levels of RECQL4 protein were significantly associated with aggressive tumor behavior, including lymph node positivity, larger tumor size, HER2 overexpression, ER-negativity, triple-negative phenotypes, and poor survival22, and shRNA-mediated RECQL4 suppression in MDA-MB453 breast cancer cells significantly inhibited in vitro clonogenic survival and in vivo tumorigenicity24.