HAUSP compartmentalization in chronic myeloid leukemia

PTEN plays an essential role in the pathogenesis of chronic myeloid leukemia. Recently, we have shown that BCR-ABL promotes PTEN nuclear exclusion, through the modulation of HAUSP activity.

Here, we investigate HAUSP cellular compartmentalization in primary CML samples.

While in normal CD34 positive cells HAUSP is expressed mostly in the nucleus, in CML CD34 cells HAUSP is expressed both in the nuclear bodies and in the cytoplasm.

This observation suggests that HAUSP behaves as a shuttling protein in CML. It can bind to BCR-ABL in the cytosol, where it is phosphorylated on tyrosine residues, and it maintains the proper compartmentalization in the nuclear bodies, where it acts as part of a PML network to regulate PTEN de-ubiquitination.