Title:PTEN, Insulin Resistance and Cancer
VOLUME: 23 ISSUE: 25
Author(s): Aiqing Li*, Minzi Qiu, Hongbo Zhou, Tao Wang and Wen Guo*
Affiliation:State Key Laboratory of Organ Failure Research, National Clinical Research Center of Kidney Disease, Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, State Key Laboratory of Organ Failure Research, National Clinical Research Center of Kidney Disease, Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, Department of Biomedicine, Southern Medical University, Guangzhou, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou
Keywords:PTEN, PI3K/ Akt signaling, insulin/IGF system signaling, insulin resistance, cancer, GLUT-4.
Abstract:Background: The tumor suppressor PTEN serves as a negative regulator of PI3K/PTEN/Akt signaling
pathway that regulates cellular functions such as cell growth, differentiation, proliferation and migration. The
PI3K/PTEN/Akt signaling cascades might also have effect on glucose uptake via translocation of GLUT-4. Insulin
controls energy storage and the whole body glucose homeostasis. Its binding to insulin receptor on the surface
of diverse cells allows glucose entry into cells, and activates a variety of cellular actions. Insulin resistance is a
common metabolic feature and established risk factor of many diseases. Its fundamental principle is inability of
insulin to exert its normal metabolic effects, and nutrient imbalance and abnormal lipid accumulation in skeletal
muscle, liver and adipose tissues.
Methods: We review the literature on the structure and function of PTEN and its involvement in insulin resistance
and tumor regulation, and summarized the detailed scientific achievements on this topic.
Results: Suppressing PTEN expression plays a role in pro- or anti-inflammatory state during insulin resistance
associated with obesity. Selective disruption of PTEN in pancreatic α-cells demonstrates that a lack of PTEN
reduces circulating glucagon levels and protects against hyperglycemia and insulin resistance in high-fat diet–fed
mice. Loss-of-function PTEN mutations in adipose tissue results in systemic glucose tolerance and insulin sensitivity
improvement because of ascended recruitment of the GLUT-4 towards the membrane. Targeting tissuespecific
PTEN deletion improves insulin sensitivity and protects from systemic insulin resistance. PTEN, as an
important tumor suppressor gene, is frequently deleted or mutated in a variety of human tumors. Inactivation of
PTEN by loss-of-function mutations leads to deregulated hyperproliferation of cells, leading to oncogenic transformation.
Conclusion: Considering PTEN's important role in insulin resistance and tumor regulation, targeting the PTEN
gene and/or protein will likely provide an efficient strategy for therapeutic intervention in cancer and metabolic
diseases like type 2 diabetes mellitus, obesity, and cardiovascular dysfunction.
