Fig. 7

A model of RSV inhibiting NKTCL cells. We make a hypothesis about the mechanisms of RSV inhibiting NKTCL. RSV inhibits NKTCL cell proliferation, induces cell cycle arrest and apoptosis through down-regulating the activities of AKT and Stat3 and inducing DDR. Down-regulated pAKT leads to up-regulation of pro-apoptotic protein Bad and Bax, which then activate the cleaved caspase-9 and caspase-3, resulting in cell apoptosis via mitochondrial pathway. On the other hand, down-regulated AKT causes p53 activated. By inducing DDR directly or via increasing Zta of EBV, RSV phosphorylates ATM, Chk2 and p53, subsequently inhibits Cyclin A2, which leads to S phase cell cycle arrest. p53 can also up-regulate Bax and Bad and activate caspase cascade, which ultimately leads to apoptosis