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1.  C/EBPα and MYB regulate FLT3 expression in AML 
Leukemia  2013;27(7):1487-1496.
The interaction between the receptor FLT3 (FMS-like tyrosine kinase-3) and its ligand FL leads to crucial signalling during the early stages of the commitment of haematopoietic stem cells. Mutation or over-expression of the FLT3 gene, leading to constitutive signalling, enhances the survival and expansion of a variety of leukaemias and is associated with an unfavourable clinical outcome for acute myeloid leukaemia (AML) patients. In this study, we used a murine cellular model for AML and primary leukaemic cells from AML patients to investigate the molecular mechanisms underlying the regulation of FLT3 gene expression and identify its key cis- and trans-regulators. By assessing DNA accessibility and epigenetic markings, we defined regulatory domains in the FLT3 promoter and first intron. These elements permit in vivo binding of several AML-related transcription factors, including the proto-oncogene MYB and the CCAAT/enhancer binding protein C/EBPα, which are recruited to the FLT3 promoter and intronic module, respectively. Substantiating their relevance to the human disease, our analysis of gene expression profiling arrays from AML patients uncovered significant correlations between FLT3 expression level and that of MYB and CEBPA. The latter relationship permits discrimination between patients with CEBPA mono- and bi-allelic mutations, and thus connects two major prognostic factors for AML.
PMCID: PMC4214120  PMID: 23340802
AML; C/EBP alpha; FLT3; MYB; regulation
2.  Distinct regulation of c-myb gene expression by HoxA9, Meis1 and Pbx proteins in normal hematopoietic progenitors and transformed myeloid cells 
Blood Cancer Journal  2012;2(6):e76-.
The proto-oncogenic protein c-Myb is an essential regulator of hematopoiesis and is frequently deregulated in hematological diseases such as lymphoma and leukemia. To gain insight into the mechanisms underlying the aberrant expression of c-Myb in myeloid leukemia, we analyzed and compared c-myb gene transcriptional regulation using two cell lines modeling normal hematopoietic progenitor cells (HPCs) and transformed myelomonocytic blasts. We report that the transcription factors HoxA9, Meis1, Pbx1 and Pbx2 bind in vivo to the c-myb locus and maintain its expression through different mechanisms in HPCs and leukemic cells. Our analysis also points to a critical role for Pbx2 in deregulating c-myb expression in murine myeloid cells cotransformed by the cooperative activity of HoxA9 and Meis1. This effect is associated with an intronic positioning of epigenetic marks and RNA polymerase II binding in the orthologous region of a previously described alternative promoter for c-myb. Taken together, our results could provide a first hint to explain the abnormal expression of c-myb in leukemic cells.
PMCID: PMC3389162  PMID: 22829978
c-myb; hematopoietic progenitors; myeloid leukemia; Hox and TALE proteins
3.  Trastuzumab-Induced Myocardiotoxicity Mimicking Acute Coronary Syndrome 
Case Reports in Oncology  2012;5(1):125-133.
Trastuzumab is an important biological agent in the treatment of HER2-positive breast cancer, with effects on response rates, progression-free survival, overall survival and quality of life. Although this drug is well tolerated in terms of adverse effects, trastuzumab-associated myocardiotoxicity has been described to have an incidence of 0.6–4.5% and in rare cases, the drug can trigger severe congestive heart failure with progression to death or even mimic acute coronary syndrome with complete left bundle branch blockade. In this paper is reported a case of trastuzumab-associated myocardiotoxicity manifesting as acute coronary syndrome in a 69-year-old female. The patient is currently undergoing a conservative clinical treatment that restricts overexertion.
The majority of clinical studies report trastuzumab-induced cardiotoxicity as a rare event, and, when present, characterized by mild to moderate clinical signs, the ease of reversibility with pharmacological measures and the temporary discontinuation of the medication. Conversely, it is vital for the oncologist/cardiologist to consider the possibility that trastuzumab-induced cardiotoxicity may manifest itself as a severe clinical case, mimicking acute coronary syndrome, justifying careful risk stratification and adequate cardiac monitoring, especially in high-risk patients.
PMCID: PMC3364043  PMID: 22666200
Breast cancer; Trastuzumab; Myocardiotoxicity; Acute coronary syndrome

Results 1-3 (3)