Therefore, in vitro datasets were selected as measured responses that could be related to the mechanistic understanding related to PFOA toxicity and observations in human exposure studies, such as, estrogen receptor binding activation associated with breast cancer, pregnane X receptor binding associated with hepatic steatosis, thyroid hormone receptor α binding leading to thyroid disease, and immunotoxicity (pro-inflammation from cytokines). This evidence concerns the gene ESR1 and breast carcinoma.