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Mechanisms of apoptosis induction by simultaneous inhibition of PI3K and FLT3-ITD in AML cells in the hypoxic bone marrow microenvironment.

ABSTRACT: We investigated the antileukemia effects and molecular mechanisms of apoptosis induction by simultaneous blockade of PI3K and mutant FLT3 in AML cells grown under hypoxia in co-cultures with bone marrow stromal cells. Combined treatment with selective class I PI3K inhibitor GDC-0941 and sorafenib reversed the protective effects of bone marrow stromal cells on FLT3-mutant AML cells in hypoxia, which was associated with downregulation of Pim-1 and Mcl-1 expression levels. These findings suggest that combined inhibition of PI3K and FLT3-ITD may constitute a targeted approach to eradicating chemoresistant AML cells sequestered in hypoxic bone marrow niches.

SUBMITTER: Jin L

PROVIDER: S-EPMC3572533 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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Mechanisms of apoptosis induction by simultaneous inhibition of PI3K and FLT3-ITD in AML cells in the hypoxic bone marrow microenvironment.

Jin Linhua L Tabe Yoko Y Lu Hongbo H Borthakur Gautam G Miida Takashi T Kantarjian Hagop H Andreeff Michael M Konopleva Marina M

Cancer letters 20121002 1

We investigated the antileukemia effects and molecular mechanisms of apoptosis induction by simultaneous blockade of PI3K and mutant FLT3 in AML cells grown under hypoxia in co-cultures with bone marrow stromal cells. Combined treatment with selective class I PI3K inhibitor GDC-0941 and sorafenib reversed the protective effects of bone marrow stromal cells on FLT3-mutant AML cells in hypoxia, which was associated with downregulation of Pim-1 and Mcl-1 expression levels. These findings suggest th ...[more]

PMID: 23036488

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