In the present study we verified that PepO acts as a TLR2/4 dual ligand agonist resulting in switching M2 macrophage to the tumoricidal M1 macrophage by activating PI3K-AKT-mTOR and inhibiting JAK2-STAT3 pathway and enhanced the anti-tumor property of the chemotherapeutic drug doxorubicin. This evidence concerns the gene STAT3 and neoplasm.