IGF1R and breast cancer: Chen and Sun (2012) also proved that the anticancer mechanism of formononetin on breast cancer cells was linked to activation of p38 MAPK pathway. The apoptosis effect of formononetin was attenuated via the pretreatment of breast cancer cell with p38 inhibitor SB203580. Moreover, a study by Huang et al. (2014) suggested that activation of p38 pathway by formononetin could be mediated via the suppression of IGF1-R expression, subsequently leading to the activation of pro-apoptosis cascade in PC-3 prostate cancer cells.