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Comment
. 2015 Jul;5(7):697-700.
doi: 10.1158/2159-8290.CD-15-0609.

INPP4B Is a Tumor Suppressor in the Context of PTEN Deficiency

Thanh-Trang T Vo  1 , David A Fruman  2
Affiliations
Comment

INPP4B Is a Tumor Suppressor in the Context of PTEN Deficiency

Thanh-Trang T Vo et al. Cancer Discov. 2015 Jul.

Abstract

Enzymes (PI3K and PTEN) controlling cellular levels of 3-phosphorylated phosphoinositides are known as important drivers or suppressors of tumorigenesis in various cancers. In this issue of Cancer Discovery, Kofuji and colleagues and Chew and colleagues identify the lipid phosphatase INPP4B as a context-specific tumor suppressor that controls phosphoinositide levels and AKT2 activation in PTEN-deficient cells.

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Conflict of interest statement

The authors disclose no conflicts of interest.

Figures

Figure 1
Figure 1
Model mechanisms of how INPP4B acts as a tumor suppressor by reducing AKT2 activation. In the classical model INPP4B reduces PtdIns(3,4)P2 at the plasma membrane. The PIP3 threshold model by Kofuji and colleagues proposes that when PTEN is absent, INPP4B restrains PtdIns(3,4,5)P3 levels by directly dephosphorylating this lipid to PtdIns(4,5)P2. The compartmentalization model by Chew and colleagues proposes that INPP4B reduces AKT2 activation specifically at the endosome by degrading PtdIns(3,4)P2 produced by PI3K-C2α.
See this image and copyright information in PMC

Comment on

References

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