PTEN and neoplasm: Hamada et al. revealed that PTEN deficiency in ECs accelerates tumor growth by promoting angiogenesis [24], and Koide et al. found that apoptosis regulator through modulating IAP expression (ARIA) increases membrane-associated PTEN expression while its knockdown leads to an opposite effect, therefore amplifying PI3K/Akt signaling, identifying that ARIA enhances PTEN activation and consequently reduces the PI3K/Akt signaling in ECs and EPCs, leading to the negative regulation in angiogenesis and vasculogenesis [26].