FFAR4 and breast carcinoma: Interestingly, in HRPBC patients, FFAR4 expression was associated with higher Ki-67 index (P = 0.008) and to a lesser extent, worse histological grade (P = 0.087) (Table 1), suggesting that higher FFAR4 expression in HRPBC patients might be associated with more aggressive breast cancer phenotypes in HRPBC.