Francesca Giacobbi

Cytogenetic conversion in a case of polycythaemia vera treated with interferon-alpha.

Summary Polycythaemia vera is a clonal disorder of the haemopoietic stem cell causing a pathologic expansion of the erythroid and sometimes the megakaryocytic and myeloid elements. In order to avoid the possible mutagenic effects of radioactive phosphorus, alkylating agents and hydroxyurea, since 1988 α‐IFN has been used for the treatment of PV and has been shown to induce and maintain haematological remission. We describe a 24‐year‐old PV patient with chromosomal abnormalities who achieved not only a reduction of the proliferation of erythroid elements and reticulin content in the bone marrow, but also a complete cytogenetic remission after IFN treatment.

Mesenchymal progenitors aging highlights a mir-196 switch targeting HOXB7 as master regulator of proliferation and osteogenesis

Human aging is associated with a decrease in tissue functions combined with a decline in stem cells frequency and activity followed by a loss of regenerative capacity. The molecular mechanisms behind this senescence remain largely obscure, precluding targeted approaches to counteract aging. Focusing on mesenchymal stromal/stem cells (MSC) as known adult progenitors, we identified a specific switch in miRNA expression during aging, revealing a miR‐196a upregulation which was inversely correlated with MSC proliferation through HOXB7 targeting. A forced HOXB7 expression was associated with an improved cell growth, a reduction of senescence, and an improved osteogenesis linked to a dramatic increase of autocrine basic fibroblast growth factor secretion. These findings, along with the progressive decrease of HOXB7 levels observed during skeletal aging in mice, indicate HOXB7 as a master factor driving progenitors behavior lifetime, providing a better understanding of bone senescence and leading to an optimization of MSC performance. Stem Cells 2015;33:939–950

Chronic eosinophilic leukaemia with ETV6-NTRK3 fusion transcript in an elderly patient affected with pancreatic carcinoma

To the Editor: An 82-yr-old woman with previous history of breast cancer, surgically treated in 1992, and arterial hypertension underwent distal pancreatectomy and splenectomy in July 2008 for a poorly differentiated adenocarcinoma of the pancreatic tail with regional lymph nodes and liver metastases. She was subsequently started on palliative chemotherapeutic treatment, consisting of gemcitabine 1000 mg ⁄m days 1 and 8 every 3 wk. On February 2009, having completed eight cycles, the chemotherapy was withdrawn because hepatic metastases increased in size and number. Until March 2009, the complete blood count was unrevealing (WBC count 7.2 · 10 ⁄L with a normal differential count, Hb 10.2 g ⁄dL, Plt count 300 · 10 ⁄L). One month later, the patient was admitted because of low-grade fever, bone pain and marked fatigue. The laboratory investigations revealed leukocytosis with marked eosinophilia and thrombocytopenia (WBC count 73 · 10 ⁄L with eosinophils 78%, Hb 11.4 g ⁄dL, Plt count 69 · 10 ⁄L). The diagnostic work-up excluded either allergic reactions or parasitic infestations or autoimmune disorders or T-cell populations with an abnormal phenotype (1, 2), raising the hypothesis of an eosinophilic leukaemoid reaction secondary to the metastatic pancreatic cancer (3). However, the morphological examination of peripheral blood (PB) smear showed eosinophilia accompanied with circulating myeloid immature precursors and blasts (3%) (Fig. 1A), while bone marrow (BM) trephine biopsy documented marked proliferation of eosinophil granulocytopoiesis, with a blast cell count < 20% (Fig. 1B). Moreover, moderate to severe BM fibrosis was documented on Gomori methenamine silver staining (not shown). These morphological pictures were consistent with a myeloproliferative neoplasm with eosinophilia (MNE) (4). Unfortunately, serum tryptase level was not measured. Extensive FISH and molecular studies on both PB and BM samples failed to detect PDGFRA, PDGFRB and FGFR1 rearrangements (4), but the clonality of the myeloid population was confirmed by further cytogenetic and FISH studies. In particular, conventional G-banding showed 46, XX, )7, +8 karyotype (Fig. 2A), while whole chromosome painting and metaphase FISH examinations performed with specific probes showed that ETV6 gene, located on 12p13, was cryptically rearranged with 15q25 (Fig. 2B,C). A submicroscopic t(12;15)(p13;q25) resulting in the fusion gene ETV6-NTRK3 on der(15) was thus documented. Moreover, RNA isolated from the BM sample was subjected to reverse transcriptase–PCR using primers designed to amplify either the 731-bp solid cancer ETV6-NTRK3 variant (5) or the 601-bp acute myeloid leukaemia (AML) ETV6-NTRK3 variant (6). These latter molecular analyses demonstrated the 731and 1265-bp products, respectively, as expected when the solid cancer-associated fusion transcript is detected (Fig. 2D). Both FISH and molecular examinations, performed as described (7) on formalin-fixed paraffinembedded pancreatic carcinoma sections, were negative for ETV6-NTRK3 fusion transcript, whereas amplification of ETV6 gene was documented (not shown).

Angiopoietin-2 expression in B-cell chronic lymphocytic leukemia: association with clinical outcome and immunoglobulin heavy-chain mutational status.

Angiopoietin-2 expression in B-cell chronic lymphocytic leukemia: association with clinical outcome and immunoglobulin heavy-chain mutational status

Chronic myeloid leukemia with thrombocythemic onset may be associated with different BCR/ABL variant transcripts

Ph-positive chronic myeloid leukemia (CML) mimicking essential thrombocythemia (ET) at onset seems to be a distinct clinical entity. Whether this rare clinical form of CML is associated with single, specific variants of BCR/ABL transcripts is a matter of debate. Among 82 consecutive patients with Ph-positive CML, we identified 3 patients in which the disease mimicked ET at presentation, because of marked thrombocytosis and moderate leukocytosis, with few immature myeloid cells in peripheral blood and blood basophilia in 2 of them. Molecular analysis with the reverse transcriptase-polymerase chain reaction technique showed the presence of b2a2, b3a2, and b3a2-b2a2 transcript variants in the three patients, respectively. The results of our study together with a review of literature data suggest that different BCR/ABL transcript variants may occur in CML mimicking ET, without an apparently significant prevalence of one type.

Chromosome rearrangements at telomeric level in hematologic disorders

Following retrospective screening of our karyotype data from 414 consecutive non-childhood, neoplastic, and preneoplastic hematologic diseases, we have isolated 11 cases with alterations involving one or two chromosome termini, including: a) nonclonal telomeric telomeric associations (tas), b) subclonal terminal rearrangements consisting of additional (add) material of unknown origin fused at the end of the chromosome, c) clonal telomere-centromere fusion (t telcen) with pseudodicentric structure. Most of these abnormalities were present in karyotypes with multiple alterations and associated to an evolutive stage of the disease (9 of 94 cases studied in progression, including three of 22 CML studied in blast crisis). The immunophenotype of the cell populations was lymphoid in eight cases, six of which were NHL, and myeloid, erythroid, and undifferentiated in the other three. More data on telomeric abnormalities may clarify whether there is ubiquitous genomic instability of neoplastic cells or an inborn cell lineage predisposition favoring rearrangements involving telomeres.

Late-Appearing PML/RARα Fusion Transcript with Coincidental t(12;13)(p13.2;q14) in Acute Promyelocytic Leukemia Lacking the t(15;17) Cytogenetic Anomaly

The late appearance of a cytogenetic/molecular hallmark in human leukemias is a rare event. We report on a case of acute myeloid leukemia with morphology, immunophenotype and clinical features typical of promyelocytic subtype (APL), in which the specific PML/RARalpha gene rearrangement was molecularly detected only at second relapse of disease, without cytogenetic evidence of the t(15;17). The emergence of the PML/RARalpha gene may be therapy-related or may represent the exceptional result of a clonal evolution during progression of neoplasia. At second relapse, a novel cell clone bearing a t(12;13)(p13.2;q14) was also observed and a molecular deletion and rearrangement of a locus at 13q14, distinct from retinoblastoma (Rb1) locus, was found. In this unusual case, the PML/RARalpha product seems to be not essential for the expression of the promyelocytic phenotype at diagnosis and, when detectable, it is not the sole genetic defect.

The importance of cytogenetic and molecular analyses in eosinophilia-associated myeloproliferative neoplasms: an unusual case with normal karyotype and TNIP1- PDGFRB rearrangement and overview of PDGFRB partner genes

Fusion genes derived from the platelet-derived growth factor receptor beta (PDGFRB) or alpha (PDGFRA) play an important role in the pathogenesis of eosinophilia-associated myeloproliferative neopla...

Occurence of a novel t(11;19)(q13;q13.3) in complete remission of acute promyelocytic leukemia

Abstract A woman with t(15;17) and PMLIRARa positive acute promyelocytic leukemia (APL-M3v) achieved a complete remission (CR) with cytogenetic and molecular conversion, after one-month ATRA plus idarubicin treatment. During CR, less than one-month after consolidation therapy with topoisomerase II inhibitors, a novel t(11;19) (q13;q13.3) was detected in peripheral blood stem cells and later in harvest bone marrow cells. Persisting CR and the negativity for BCL1 and PRAD1 genes rearrangement, the autotransplantation was performed, with good outcome. The patient is still in CR eighteen months post-transplant, in spite of the persistence of a small t(11;19) clone in BM cells. The emergence of a novel chromosomal change during CR of acute leukemia is a rare phenomenon. This is the first t(11;19)(q13;q13.3) described in APL. This finding raises the issue of whether the abnormal karyotypes at remission might represent a risk of tumor recurrence. The meaning of this genomic instability is yet unknown.

NPM1 mutations may reveal acute myeloid leukemia in cases otherwise morphologically diagnosed as myelodysplastic syndromes or myelodysplastic/myeloproliferative neoplasms.

Nucleophosmin 1 (NPM1) gene mutations, resulting in aberrant cytoplasmic delocalization of NPM1 (NPMc+), are detected in about 30% of all de novo acute myeloid leukemia (AML) cases, and in 50–60% o...