ZNF217, a notable member of this class of genes, is a Krüppel-like finger (KLF) protein that acts as a transcriptional regulator that amplifies the estrogen response in breast cancer (Cohen et al. 2015) and has been identified as a biomarker of poor survival in patients with Luminal A (ER+) breast tumors (Frietze et al. 2014). This evidence concerns the gene ZNF217 and breast carcinoma.