MTOR and cancer: Given the high involvement of AKT-mTOR signaling in dictating cancer resistance to both small-molecule targeted drugs and biological agents [35], we evaluated the impact of silencing of circPDHK1 (si-circPDHK1) on the anti-tumor efficacy of tyrosine kinase inhibitors (TKI), PI3K-AKT inhibitor, or mTOR inhibitor.