The role of Akt and NF- κB signaling in drug resistance mechanism of tumor cells. Several drugs induce the activation of Akt and NF-κB signaling pathways. Akt activation inhibits the P53 and BAD pathways leading to cell survival. Akt also stimulates Ikk, which inhibits IκB and triggers NF-κB signaling pathway. NF-κB activates C-Myc and COX 2 that are mainly involved in cell proliferation and angiogenesis, respectively. Both Akt and NF-κB activate the antiapoptotic proteins Bcl-2 and Bcl-xL, inhibiting the Cytochrome-c release from mitochondria, and Cyclin D1, which contributes to cell cycle progression. Akt and NF-κB also inhibit the caspase cascade by XIAP and Survivin activation, respectively.