How moderate changes in Akt T-loop phosphorylation impact on tumorigenesis and insulin resistance

Stephan Wullschleger, Kei Sakamoto, Lana Johnstone, Suzanne Duce, Stewart Fleming, Dario R. Alessi

    Research output: Contribution to journalArticlepeer-review

    10 Citations (Scopus)

    Abstract

    The Akt signalling pathway plays vital roles in controlling cellular responses to insulin as well as in proliferation and survival. Inhibition of Akt signalling leads to insulin resistance and type 2 diabetes, whereas hyperactivation of Akt promotes tumorigenesis. In this study, we investigate how modest changes in the activity of the Akt signalling pathway, to an extent that might be achieved by drug treatment, would impact on insulin resistance and tumorigenesis. Using insulin-resistant PDK1(K465E/K465E) PH domain knock-in mice, we found that introducing the PTEN+/- mutation to slightly stimulate Akt restored normal insulin sensitivity. Introducing the PDK1(K46SE/K465E) PH domain knock-in mutation into cancer-prone PTEN+/- mice, lowered Akt activity only by about 50%, but led to a delay in tumour onset of similar to 4 months in a broad range of tumours. This was also accompanied by slower growth of B cell follicular lymphomas, as monitored by magnetic resonance imaging. Our findings imply that signal transduction inhibitors that lead to a modest reduction in Akt activity would not only delay onset of tumours possessing elevated phosphoinositide 3-kinase pathway activity but would also reduce the growth rate of developed tumours.

    Original languageEnglish
    Pages (from-to)95-103
    Number of pages9
    JournalDisease Models & Mechanisms
    Volume4
    Issue number1
    DOIs
    Publication statusPublished - Jan 2011

    Keywords

    • PROTEIN-KINASE 1
    • MTOR COMPLEX 2
    • TUMOR-SUPPRESSOR
    • CANCER SUSCEPTIBILITY
    • PTEN
    • MUTATION
    • MICE
    • METABOLISM
    • PHOSPHATASE
    • PTEN/MMAC1

    Cite this