inositol-3-4-5-trisphosphate and Neoplasms

The tumour suppressor PTEN has been implicated in a large number of human tumours and is conserved from humans to worms. Characterization of PTEN protein showed that it is a phosphatase that acts on proteins and on 3-phosphorylated phosphoinositides, including phosphatidylinositol (3,4,5)-trisphosphate, and can therefore modulate signal-transduction pathways that involve lipid second messengers. Recent results indicate that at least part of its role is to regulate the activity of the serine/threonine kinase AKT/PKB, and thus influence cell survival signalling. This article discusses the function of PTEN and how this could be linked to its activity as a tumour suppressor.

Topics: Amino Acid Sequence; Animals; DNA Mutational Analysis; DNA, Neoplasm; Evolution, Molecular; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Neoplastic; Genes, Lethal; Genes, Tumor Suppressor; Helminth Proteins; Humans; Inositol Phosphates; Invertebrates; Mammals; Mice; Mice, Knockout; Molecular Sequence Data; Neoplasms; Phosphatidylinositols; Phospholipids; Phosphoric Monoester Hydrolases; Phosphorylation; PTEN Phosphohydrolase; Saccharomyces cerevisiae; Sequence Alignment; Sequence Homology, Amino Acid; Species Specificity; Substrate Specificity; Tumor Suppressor Proteins