STK11 and breast cancer: For example, in breast cancer treatment, the use of Akt inhibitors upregulates VPS34-dependent SGK3 signaling.25 Another kinase regulated by VPS34 is intimal LKB1 liver kinase B1 (LKB1; also known as STK11), an AMPK activator and a positive regulator of cell polarity and epithelial tissue.26 VPS34 and mTOR complex 1 (mTORC1) signaling have been shown to be correlated.