BCL2L10 positive cells in bone marrow are an independent prognostic factor of azacitidine outcome in myelodysplastic syndrome and acute myeloid leukemia.

Azacitidine (AZA), the reference treatment for most higher-risk myelodysplastic (MDS) patients can also improve overall survival (OS) in elderly acute myeloid leukemia (AML) patients ineligible for intensive chemotherapy, but reliable biological markers predicting response and OS in patients treated with AZA are lacking. In a preliminary study, we found that an increase of the percentage of BCL2L10, an anti-apoptotic member of the bcl-2 family, was correlated with AZA resistance. In this study, we assessed prospectively by flow cytometry the prognostic value of BCL2L10 positive bone marrow mononuclear cells in 70 patients (42 MDS and 28 AML), prior to AZA treatment.

Post transcriptional control of the epigenetic stem cell regulator PLZF by sirtuin and HDAC deacetylases.

Background: The transcriptional repressor promyelocytic leukemia zinc finger protein (PLZF) is critical for the regulation of normal stem cells maintenance by establishing specific epigenetic landscape. We have previously shown that CBP/p300 acetyltransferase induces PLZF acetylation in order to increase its deoxynucleotidic acid (DNA) binding activity and to enhance its epigenetic function (repression of PLZF target genes). However, how PLZF is inactivated is not yet understood.

CD44 activation enhances acute monoblastic leukemia cell survival via Mcl-1 upregulation.

Survival of acute myeloid leukemia (AML) cells is regulated by their adherence to bone marrow stromal environment. Several adhesion molecules mediate interactions between AML cells and stroma, but their specific role in AML cell survival is still poorly understood. Here, we show that CD44 activation with the Hermes-3 monoclonal antibody enhances primary AML5 blast survival and increases apoptosis resistance of THP-1 monoblastic leukemia cells.

The effect of anti-CD44 monoclonal antibodies on differentiation and proliferation of human acute myeloid leukemia cells.

Acute myeloid leukemia (AML) is a clonal malignant disease characterized by an increasing number of immature myeloid cells arrested at various stages of granulocytic and monocytic differentiation. The stage of the blockage defines distinct AML subtypes (AML1 to AML5 are the most frequent ones). There is increasing evidence that the malignant clone is maintained by rare AML stem cells endowed with self-renewal capacity, which through extensive proliferation coupled to partial differentiation, generate leukemic progenitors and blasts, of which the vast majority have limited proliferative capacity.

CD44: a new means to inhibit acute myeloid leukemia cell proliferation via p27Kip1.

Acute myeloid leukemia (AML) is sustained by the extensive proliferation of leukemic stem and progenitor cells, which give rise to the population of leukemic blasts with defective differentiation and low proliferative capacity. We have recently shown that ligation of CD44, a cell surface molecule present on AML cells, with specific monoclonal antibodies (mAbs) inhibits their proliferation. However, its mechanism has not been investigated yet.