It has been reported that activation of pim-1 proto-oncogene (PIM)22, p110β23, pyruvate dehydrogenase kinase 1 (PDK1)-serum/glucocorticoid-regulated kinase 1 (SGK1)24, and estrogen receptor25 mediated the resistance to PI3K inhibitors in breast cancer. Here, PDK1 is linked to breast cancer.