1: Br J Haematol. 2005 Jul;130(2):233-48. 

Routine expression profiling of microarray gene signatures in acute leukaemia by
real-time PCR of human bone marrow.

Sakhinia E, Faranghpour M, Liu Yin JA, Brady G, Hoyland JA, Byers RJ.

Division of Laboratory and Regenerative Medicine, School of Medicine, Faculty of
Medical and Human Sciences, The University of Manchester, Manchester, UK.

Cancer subtype diagnosis using microarray signatures has the potential to
transform pathological diagnosis but the routine measurement of genes signatures
remains difficult. Reverse transcription polymerase chain reaction (RT-PCR)
measurement of Indicator genes for acute myeloid leukaemia (AML) and acute
lymphoblastic leukaemia (ALL) was used to determine gene signatures. Bone marrow
(BM) mononuclear cells were sorted into total, CD34(+) and CD34(-) fractions,
and mRNAs globally amplified from each fraction using polyA PCR. The expression
profile of the 17 top-ranked genes distinguishing AML and ALL were measured by
RT-PCR in five ALL, 26 AML, 12 AML remission, four chronic myeloid leukaemia
(CML) and nine morphologically normal BM samples. All but two of the genes
measured showed similar expression in AML and ALL to that reported previously.
Specifically, c-MYB (P </= 0.04) was significantly increased in ALL in the total
fraction, whilst HOXA9 (P </= 0.19) and cystatin c (P </= 0.01) were increased
in AML in the CD34(+) and CD34(-) fractions, respectively. c-MYB, hSNF2, RBAP48,
HKRT-1, LYN, CD33, Adipsin and HOXA9 were increased in AML compared with
remission AML, indicating an ability to determine disease activity. The method
used is simple, sensitive and robust, enabling routine clinical use, and it can
also be extended to other tumours types with gene signatures.

PMID: 16029452 [PubMed - indexed for MEDLINE]


---------------------------------------------------------------


2: Mol Cell Biol. 2000 May;20(9):3274-85. 

Hoxa9 immortalizes a granulocyte-macrophage colony-stimulating factor-dependent
promyelocyte capable of biphenotypic differentiation to neutrophils or
macrophages, independent of enforced meis expression.

Calvo KR, Sykes DB, Pasillas M, Kamps MP.

Department of Pathology, School of Medicine, University of California San Diego,
La Jolla, California 92093-0612, USA. krcalvo@ucsd.edu

The genes encoding Hoxa9 and Meis1 are transcriptionally coactivated in a subset
of acute myeloid leukemia (AML) in mice. In marrow reconstitution experiments,
coexpression of both genes produces rapid AML, while neither gene alone
generates overt leukemia. Although Hoxa9 and Meis1 can bind DNA as heterodimers,
both can also heterodimerize with Pbx proteins. Thus, while their coactivation
may result from the necessity to bind promoters as heterodimers, it may also
result from the necessity of altering independent biochemical pathways that
cooperate to generate AML, either as monomers or as heterodimers with Pbx
proteins. Here we demonstrate that constitutive expression of Hoxa9 in primary
murine marrow immortalizes a late myelomonocytic progenitor, preventing it from
executing terminal differentiation to granulocytes or monocytes in the presence
of granulocyte-macrophage colony-stimulating factor (GM-CSF) or interleukin-3.
This immortalized phenotype is achieved in the absence of endogenous or
exogenous Meis gene expression. The Hoxa9-immortalized progenitor exhibited a
promyelocytic transcriptional profile, expressing PU.1, AML1, c-Myb, C/EBP
alpha, and C/EBP epsilon as well as their target genes, the receptors for
GM-CSF, G-CSF, and M-CSF and the primary granule proteins myeloperoxidase and
neutrophil elastase. G-CSF obviated the differentiation block of Hoxa9, inducing
neutrophilic differentiation with accompanying expression of neutrophil
gelatinase B and upregulation of gp91phox. M-CSF also obviated the
differentiation block, inducing monocytic differentiation with accompanying
expression of the macrophage acetyl-low-density lipoprotein scavenger receptor
and F4/80 antigen. Versions of Hoxa9 lacking the ANWL Pbx interaction motif
(PIM) also immortalized a promyelocytic progenitor with intrinsic biphenotypic
differentiation potential. Therefore, Hoxa9 evokes a cytokine-selective block in
differentiation by a mechanism that does not require Meis gene expression or
interaction with Pbx through the PIM.

PMID: 10757811 [PubMed - indexed for MEDLINE]


---------------------------------------------------------------