Jose Roman

Disparity for the minor histocompatibility antigen HA-1 is associated with an increased risk of acute graft-versus-host disease (GvHD) but it does not affect chronic GvHD incidence, disease-free survival or overall survival after allogeneic human leucocyte antigen-identical sibling donor transplantation

Disparity for the minor histocompatibility antigen HA‐1 between patient and donor has been associated with an increased risk of acute graft‐versus‐host disease (GvHD) after allogeneic human leucocyte antigen (HLA)‐identical sibling donor stem cell transplantation (SCT). However, no data concerning the impact of such disparity on chronic GvHD, relapse or overall survival are available. A retrospective multicentre study was performed on 215 HLA‐A2‐positive patients who received an HLA‐identical sibling SCT, in order to determine the differences in acute and chronic GvHD incidence on the basis of the presence or absence of the HA‐1 antigen mismatch. Disease‐free survival and overall survival were also analysed. We detected 34 patient–donor pairs mismatched for HA‐1 antigen (15·8%). Grades II–IV acute GvHD occurred in 51·6% of the HA‐1‐mismatched pairs compared with 37·1% of the non‐mismatched. The multivariate logistic regression model showed statistical significance (P: 0·035, OR: 2·96, 95% CI: 1·07–8·14). No differences were observed between the two groups for grades III–IV acute GvHD, chronic GvHD, disease‐free survival or overall survival. These results confirmed the association between HA‐1 mismatch and risk of mild acute GvHD, but HA‐1 mismatch was not associated with an increased incidence of chronic GvHD and did not affect relapse or overall survival.

NIN, a gene encoding a CEP110-like centrosomal protein, is fused to PDGFRB in a patient with a t(5;14)(q33;q24) and an imatinib-responsive myeloproliferative disorder

We describe a new PDGFRB fusion associated with a t(5;14)(q33;q24) in a patient with a longstanding chronic myeloproliferative disorder with eosinophilia. After confirmation of PDGFRB involvement and definition of the chromosome 14 breakpoint by fluorescence in situ hybridization, candidate partner genes were selected on the basis of the presence of predicted oligomerization domains believed to be an essential feature of tyrosine kinase fusion proteins. We demonstrate that the t(5;14) fuses PDGFRB to NIN, a gene encoding a centrosomal protein with CEP110-like function. After treatment with imatinib, the patient achieved hematological and cytogenetical remission, but NIN-PDGFRB mRNA remained detectable by reverse transcription-PCR.

Disruption and aberrant expression of HMGA2 as a consequence of diverse chromosomal translocations in myeloid malignancies.

Chromosomal translocations that target HMGA2 at chromosome band 12q14 are seen in a variety of malignancies, notably lipoma, pleomorphic salivary adenoma and uterine leiomyoma. Although some HMGA2 fusion genes have been reported, several lines of evidence suggest that the critical pathogenic event is the expression of truncated HMGA2 isoforms. We report here the involvement of HMGA2 in six patients with myeloid neoplasia, dysplastic features and translocations or an inversion involving chromosome bands 12q13–15 and either 7p12, 8q22, 11q23, 12p11, 14q31 or 20q11. Breaks within or very close to HMGA2 were found in all six cases by molecular cytogenetic analysis, leading to overexpression of this gene as assessed by RT-PCR. Truncated transcripts consisting of HMGA2 exons 1–2 or exons 1–3 spliced to intron-derived sequences were identified in two patients, but were not seen in controls. These findings suggest that abnormalities of HMGA2 play an important and previously unsuspected role in myelodysplasia.

Hypermethylation of the calcitonin gene in acute lymphoblastic leukaemia is associated with unfavourable clinical outcome.

We analysed calcitonin (CALC1) gene hypermethylation using semiquantitative differential polymerase chain reaction in 105 patients with adult (n = 49) and childhood (n = 56) acute lymphoblastic leukaemia (ALL), and studied the association of CALC1 hypermethylation with clinical presentation features and disease outcome. We also investigated the possible relationship between CALC1 methylation status and expression of the cell cycle inhibitor gene p57KIP2. We observed CALC1 hypermethylation in bone marrow cells from 43% (45 out of 105) of ALL patients. Clinical, molecular and laboratory features did not differ significantly between hypermethylated and hypomethylated patients, only T‐cell lineage was associated with hypermethylation (14% vs. 47%, P = 0025). Complete remission rate was similar in both groups although hypermethylated patients had a higher relapse rate (68% vs. 19%, P < 0·00001) and mortality rate (55% vs. 36%, P = 0·06) than hypomethylated patients. Estimated disease‐free survival (DFS) at 6 years was 66·1% for hypomethylated patients and 5·3% for hypermethylated patients (P < 0,00001). Multivariate analysis from potential prognostic factors demonstrated that CALC1 methylation status was an independent prognostic factor in predicting DFS (P = 0·0001). Separate analysis of adult and childhood ALL patients showed similar results to the whole series. In addition, hypermethylated patients showed downregulation of p57KIP2 expression. Our results suggest that CALC1 gene hypermethylation is associated with an enhanced risk of relapse independently of known poor‐prognostic factors and we describe, for the first time, a possible implication of the p57KIP2 gene in the genesis and prognosis of ALL.

A novel gene, MDS2, is fused to ETV6/TEL in a t(1;12)(p36.1;p13) in a patient with myelodysplastic syndrome

ETV6/TEL is the first transcription factor identified that is specifically required for hematopoiesis within the bone marrow. This gene has been found to have multiple fusion partners of which 16 have been cloned. Fluorescence in situ hybridization (FISH) analysis in a patient with myelodysplastic syndrome (MDS) revealed a t(1;12)(p36;p13) involving ETV6, with the breakpoint in this gene between exon 2 and exon 3. We report here the cloning of a novel ETV6 partner located on 1p36.1, involved in the t(1;12). 3′ RACE‐PCR from RNA identified a novel sequence fused to exon 2 of ETV6. Database searches localized this sequence in a bacterial artificial chromosome (BAC) mapped to 1p36 by fingerprint analysis. This result was confirmed by FISH using this BAC as probe. 5′ and 3′ RACE experiments with primers from this novel sequence were carried out on RNA from a healthy donor and identified a novel full‐length mRNA, which we named MDS2 (myelodysplastic syndrome 2). RT‐PCR experiments were performed on a panel of human cDNAs to analyze the expression pattern of this gene and they revealed four splicing variants. RT‐PCR analysis showed that ETV6‐MDS2, but not the reciprocal MDS2‐ETV6 fusion transcript, was expressed in the bone marrow of the patient. The product of the ETV6‐MDS2 fusion transcript predicts a short ETV6 protein containing the first 54 amino acids of ETV6 plus four novel amino acids, lacking both the PTN and the DNA‐binding domains. Possible mechanisms to account for the development of MDS in this patient are discussed.

Low prevalence of the factor V Leiden among patients with ischemic stroke

The aim of the study is to determine if a novel thrombophilia mechanism (factor V Leiden) that is associated with resistance to activated protein C (APC) is in itself a risk factor for the development of ischemic stroke (IS). Sixty-six controls and 66 patients with IS were included in an unmatched case-control study. In the group of patients selected for this study, other causes of IS were ruled out. APC resistance was considered if activated partial thromboplastin time (aPTT) measured in the presence of APC was less than 2.2 times prolonged when compared to aPTT in the absence of APC (APC ratio < 2.2). Digestion with a restriction enzyme of a previously amplified exon 10 of the gene that encodes for factor V was used to detect the presence of the factor V mutation. We identified 5 patients (prevalence: 7.5%) with APC resistance (mean age: 31 years, range: 6-52 years). Mutation in factor V gene was confirmed in three of them. In the control group we detected 3 (4.5%) low APC ratios, all of them carrying specific factor V mutation. We cannot conclude a significant association between APC resistance and IS [odds ratio: 1.72; chi 2 Mantel and Haenszel was 0.53 (p = 0.4673) and exact Fishers test p = 0.3589] but these 5 young adults suffered an episode of IS having APC resistance as the only prothrombotic condition. In conclusion, these results cannot prove a statistical association between APC resistance and IS. Further studies must be done in order to confirm that there is no relationship between APC resistance and IS in young adults when major risk factors are excluded.

Protein C, protein S, and C4b-binding protein in neonatal severe infection and septic shock

We have studied the behaviour of total protein S, free protein S, protein C and C4b-binding protein fifteen neonates with severe infections, eight with septic shock and in a group of ten healthy newborns. Protein C was decreased in shock and septic patients, but only the shock group showed significant differences compared to normal neonates. Total protein S was normal in both groups of patients, although free protein S had significantly lower values in shock and nonshock infants. C4b-binding protein was higher than normal in septic and shock patients compared to the control group. Decreased values of protein C and free protein S can be explained by the activation of coagulation and their subsequent consumption. On the other hand, the increased levels of C4b-binding protein can affect the distribution of protein S in plasma, producing a shift in protein S to the complexed inactive form. These findings can contribute to an increased risk of microthrombosis during neonatal sepsis.

E1A3 as a unique, naturally occurring BCR–ABL transcript in an indolent case of chronic myeloid leukaemia

A woman with Ph‐positive chronic myeloid leukaemia (CML) with an atypical e1a3 BCR–ABL hybrid gene is described. To our knowledge, this is the first report of this transcript type as a unique naturally occurring BCR–ABL fusion in a CML patient. This case was characterized by a low leucocyte count and a very indolent course without treatment. Because the deletion of ABL exon 2 sequences results in deletion of an essential part of the ABL SH3 domain, our case suggests that this ABL SH3 domain is not absolutely necessary for efficient induction of a myeloproliferative disease in the context of BCR–ABL/p190.

Novel type of BCR-ABL transcript in a chronic myelogenous leukaemia patient relapsed after bone marrow transplantation.

We identified a novel BCR–ABL transcript in a chronic myelogenous leukaemia (CML) patient who relapsed after bone marrow transplantation (BMT), containing a fusion between part of BCR exon 3, 44 nucleotides derived from ABL intron 1b and ABL exon 2. The breakpoints were located within BCR exon 3 on chromosome 22 and within the ABL intron 1b on chromosome 9, and the transcript derives from a splicing of ABL exon 2 to a putative splicing acceptor site 44 nucleotides downstream to the breakpoint on chromosome 9. The patients clinical course strengthens the idea that short forms of BCR–ABL transcripts are associated with a more aggressive disease.

Enfermedad de Behçet: estudio de 74 pacientes

Fundamento y objetivo: La enfermedad de Behcet (EB) es una entidad clinica poco prevalente en Espana. Son escasos los articulos publicados sobre datos epidemiologicos y manifestaciones clinicas en nuestro pais. El objetivo del presente estudio ha sido conocer las caracteristicas de las manifestaciones clinicas de la EB en la Comunidad Valenciana. Pacientes y metodo: Se recogieron datos de los pacientes diagnosticados entre 1990 y 2005 de EB en los Hospitales Universitarios La Fe, General y Doctor Peset de Valencia. Todos los pacientes cumplian los criterios diagnosticos del Grupo de Estudio Internacional para el diagnostico de la EB. Las diferencias entre sexos se analizaron mediante el test de la *2. Resultados: Formaron el grupo de estudio 74 pacientes (40 varones y 34 mujeres). Las manifestaciones clinicas mas frecuentes fueron las aftas orales (98,5%) y genitales (82,4%), seguidas de las cutaneas (64,2%), oculares (42,5%), fiebre (39,4%) y vasculares (28,4%), con predominio de las trombosis venosas sobre las arteriales. Solo las manifestaciones gastrointestinales fueron mas frecuentes en el sexo femenino (p = 0,002). Las alteraciones vasculares y oculares fueron mas graves en los varones. En cuanto a la prevalencia de los factores de riesgo cardiovascular, el 32,4% de los pacientes eran fumadores, un 20,3% presentaba hiperlipemia; un 19%, hipertension; un 13,5%, obesidad, y un 9,5%, diabetes, aunque no se observo asociacion entre estos y los episodios tromboticos ni la uveitis posterior (p > 0,05). Conclusiones: Los resultados obtenidos fueron similares a los de otras areas geograficas. Destacan la mayor frecuencia de manifestaciones digestivas en mujeres y el predominio de los episodios tromboticos venosos sobre los arteriales. Los factores de riesgo cardiovascular no parecen desempenar un papel en el desarrollo de episodios tromboticos ni uveitis posterior en estos pacientes.