FOXO3 and cancer: Although FOXOs are generally seen as tumor suppressor proteins emerging data also suggest that the FOXO transcription factor FOXO3 may even support cancer development by protecting tumor cells against oxidative stress [12], by promoting drug resistance in cooperation with other FOX transcription factors [20], activating PKB survival signaling [21], attenuating the pro-apoptotic response to hypoxia [22] and even by promoting tumor cell invasion via induction of matrix metalloproteinases [23].