PTEN is a phosphatase which metabolises PIP₃, the lipid product of PI 3-Kinase, directly opposing the activation of the oncogenic PI3K/AKT/mTOR signalling network. Accordingly, loss of function of the PTEN tumour suppressor is one of the most common events observed in many types of cancer. Although the mechanisms by which PTEN function is disrupted are diverse, the most frequently observed events are deletion of a single gene copy of PTEN and gene silencing, usually observed in tumours with little or no PTEN protein detectable by immunohistochemistry. Accordingly, with the exceptions of glioblastoma and endometrial cancer, mutations of the PTEN coding sequence are uncommon (<10%) in most types of cancer. Here we review the data relating to PTEN loss in seven common tumour types and discuss mechanisms of PTEN regulation, some of which appear to contribute to reduced PTEN protein levels in cancers.

PTEN是一种磷酸酶，可代谢PI 3-激酶的脂质产物PIP ₃，直接对抗致癌PI3K / AKT / mTOR信号网络的激活。因此，PTEN肿瘤抑制剂的功能丧失是在许多类型的癌症中观察到的最常见事件之一。尽管破坏PTEN功能的机制多种多样，但最常观察到的事件是PTEN单个基因拷贝的缺失和基因沉默，通常在几乎没有或没有PTEN蛋白可通过免疫组织化学检测到的肿瘤中观察到。因此，除了胶质母细胞瘤和子宫内膜癌外，PTEN编码序列的突变在大多数类型的癌症中并不常见（<10％）。在这里，我们回顾了与7种常见肿瘤类型中PTEN丢失有关的数据，并讨论了PTEN调节的机制，其中一些机制似乎有助于降低癌症中PTEN的蛋白水平。