IRF1 and cancer: Several features of IFNs suggest their close inter relationship with tumor-suppressor pathways: (i) IFNs possess cell growth suppression activities [53]; (ii) type I IFNs serve as a bridge between innate and adaptive immune systems which have elaborate mechanisms to eliminate virus infected and cancer cells [54]; (iii) Some IRFs, such as IRF-3 and IRF-1, act as tumor suppressor genes [55]–[57]; (iv)type I IFNs can boost the response of p53 to stress signals.