Abstract
Abl-mediated transformation requires the activation of multiple pathways involved in the cellular proliferation and survival, including PI3K/AKT and JAK/STAT-dependent Pim kinases. Recently, the E17K mutation in the AKT1 has been associated with multiple human malignancies and leukemia in mice. However, this mutation has not been identified in Abl-transformed cells. We investigated the presence of the AKT1(E17K) mutation in v-Abl-transformed cell clones. AKT1(E17K) was detected in 3 (2.6%) of 116 specimens examined. To show the involvement of AKT1(E17K) directly in v-Abl-mediated tumorigenesis, we infected bone marrow cells from mice with bicistronic retroviruses encoding v-Abl and either wild-type or the mutant AKT1. Interestingly, we found that E17K mutant greatly increased the v-Abl transformation efficiency as compared with wild-type AKT1. Ectopic expression of E17K mutant increased the expression levels of antiapoptotic protein BCL2 and phosphorylation levels of proapoptotic protein BAD. This correlated with an increased protection from imatinib-induced apoptosis in Abl transformants. Furthermore, AKT1(E17K) promotes survival of the Pim-deficient cells, indicating a functional link between AKT and Pim in v-Abl transformation. In addition, AKT1(E17K) delays loss of Pim-1 and Pim-2 protein levels on v-Abl inactivation, which suggests that there exists reciprocal signaling between AKT and Pim in v-Abl transformants.
Original language | English (US) |
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Pages (from-to) | 3845-3853 |
Number of pages | 9 |
Journal | Oncogene |
Volume | 29 |
Issue number | 26 |
DOIs | |
State | Published - Jul 1 2010 |
Externally published | Yes |
Keywords
- AKT1
- Pim
- cancer
- mutation
- v-Abl
ASJC Scopus subject areas
- Molecular Biology
- Genetics
- Cancer Research