Wip1 also plays an important role in tumorigenesis, which is evident by its overexpression in several types of human cancers such as breast cancer, ovarian cancer, and gastric carcinomas (11–14). Oncogenic stress triggers DNA damage-like signaling, which appears to act as a barrier to cellular transformation in response to oncogenic stress (15, 16), and inhibition of this signaling by Wip1 is most likely a tumor promoting mechanism. Additionally, although its overexpression alone does not promote tumorigenesis, Wip1 has been shown to cooperate with other oncogenes, including Erbb2 and HRas1, in promoting tumorigenesis (17, 18). This review will focus on the regulation of Wip1 expression after stress, the functional effects of Wip1 on signaling in the stress response, and the cooperation of Wip1 with oncogenes in promoting tumorigenesis.
