Eva Barragán

Risk-adapted treatment of acute promyelocytic leukemia with all-trans retinoic acid and anthracycline monochemotherapy: long-term outcome of the LPA 99 multicenter study by the PETHEMA Group

A previous report of the Programa de Estudio y Tratamiento de las Hemopatías Malignas (PETHEMA) Group showed that a risk-adapted strategy combining all-trans retinoic acid (ATRA) and anthracycline monochemotherapy for induction and consolidation in newly diagnosed acute promyelocytic leukemia results in an improved outcome. Here we analyze treatment outcome of an enlarged series of patients who have been followed up for a median of 65 months. From November 1999 through July 2005 (LPA99 trial), 560 patients received induction therapy with ATRA plus idarubicin. Patients achieving complete remission received 3 courses of consolidation followed by maintenance with ATRA and low-dose chemotherapy. The 5-year cumulative incidence of relapse and disease-free survival were 11% and 84%, respectively. These results compare favorably with those obtained in the previous LPA96 study (P = .019 and P = .04, respectively). This updated analysis confirms the high antileukemic efficacy, low toxicity, and high degree of compliance of a risk-adapted strategy combining ATRA and anthracycline monochemotherapy for consolidation therapy.

Wnt signaling pathway is epigenetically regulated by methylation of Wnt antagonists in acute myeloid leukemia.

Activation of the Wnt signaling pathway has been implicated recently in the pathogenesis of leukemia. We studied the function of epigenetic regulation of the Wnt pathway and its prognostic relevance in acute myelogenous leukemia (AML). We used a methylation-specific polymerase chain reaction approach to analyze the promoter methylation status of a panel of Wnt antagonists including sFRP1, sFRP2, sFRP4, sFRP5, DKK1 and DKK3. Aberrant methylation of Wnt antagonists was detected in four AML cell lines and in up to 64% of AML marrow samples. Treatment of the cell lines with 5-aza-2′-deoxycytidine induced reexpression of methylated Wnt antagonists and inactivation of the Wnt pathway by downregulating the Wnt pathway genes cyclin D1, TCF1 and LEF1 and reducing nuclear localization of β-catenin. In a subgroup of patients 60 years and younger with newly diagnosed AML and intermediate-risk cytogenetics, abnormal methylation of Wnt antagonists was associated with decreased 4-year relapse-free survival (28 vs 61%, respectively, P=0.03). Our results indicate a function of the epigenetic regulation of the Wnt pathway in predicting relapse in a subgroup of AML patients.

Profile of polymorphisms of drug-metabolising enzymes and the risk of therapy-related leukaemia

Therapy‐related acute myeloid leukaemia/myelodysplastic syndrome (t‐AML/t‐MDS) results from an impaired ability to detoxify chemotherapeutic drugs or repair drug‐induced genetic damage caused by genetic polymorphisms in enzymes involved in the metabolism of drugs. We analysed the prevalence of genetic polymorphisms of CYP1A1*2A(T6235C), CYP2E1*5B(C‐1019T), CYP3A4*1B(A‐290G), del{GSTT1}, del{GSTM1}, NQO1*2(C609T), MTHFR(C677T) and TYMS 2R/3R in 78 t‐AML/t‐MDS and 458 normal individuals (control group, CG) using real‐time and conventional polymerase chain reaction (PCR)‐based methods. The incidences of polymorphisms among t‐AML/t‐MDS patients and CG individuals were similar. However, a polymorphism profile consisting of CYP1A1*2A, del{GSTT1} and NQO1*2 strongly modified the risk of t‐AML/t‐MDS. The absence of all three polymorphisms decreased the risk of t‐AML/t‐MDS 18‐fold (odds ratio (OR) = 0·054, 95% confidence interval (CI) = 0·005–0·63, P = 0·02), whereas the presence of only NQO1*2 or all three polymorphisms enhanced the risk of t‐AML/t‐MDS (OR = 2·09, 95% CI = 1·08–4·03, P = 0·03 and OR = 18·42, 95% CI = 1·59–212·76, P = 0·02 respectively). Thus, the profiles of genetic polymorphisms of drug‐metabolising enzymes might explain the increased risk to t‐AML/t‐MDS observed in some patients treated with polychemotherapy.

Prognostic significance of c-erbB-2/neu amplification and epidermal growth factor receptor (EGFR) in primary breast cancer and theor relation to estradiol receptor (ER) status

The aim of this study is to evaluate the prognostic significance of c-erbB-2/neu amplification and epidermal growth factor receptor (EGFR) expression in primary breast cancer (BC) and their prognostic implications when combined with estradiol receptor (ER) status. In this work, 825 BCs were studied. Neu amplification was evaluated by dot-blot and EGFR expression was evaluated by ligand binding assay using I125-EGF. Neu, EGFR, estradiol and progesterone receptors (ER and PR) had a marked influence on disease free survival (DFS) in univariate analysis. In node-negative (NO) cases only neu was associated with short DFS (p = 0.005). However, in node-positive (N+) cases both EGFR (p = 0.005) and neu (p = 0.002) influenced DFS. None of the biological markers were significant predictors for overall survival (OS) in NO/BC. On the contrary, in N+/BC, EGFR + (p = 0.003) was associated with short OS. The EGFR + /neu/phenotype represented a sub-group with an even worse prognosis with respect to DFS (p = 0.0034) as well as EGFR + /ER-tumors (p = 0.005). Moreover, neu + /ER-patients also had a high probability of relapse (p = 0.0000) and death (p = 0.006). C-erbB-2/neu, EGFR, histological grade, pN, pT and ER were subjected to a Cox multivariate regression analysis: neu was the most important parameter in predicting recurrence, and EGFR was a significant predictor for OS.

Unrelated donor cord blood transplantation in adults with chronic myelogenous leukemia: results in nine patients from a single institution

The potential role of unrelated donor cord blood transplantation (UD-CBT) in adults is not well established. We report the results of UD-CBT in nine adult patients with chronic myeloid leukemia (CML). The median age was 27 years (range, 19–41 years), and the median weight was 62 kg (range, 45–78 kg). At transplant, six patients were in chronic phase (five in first, and one in second), two in blast crisis, and one in accelerated phase. Eight had received intensive chemotherapy, and three had undergone autologous peripheral blood hematopoietic stem cell transplantation. Four had received interferon with no cytogenetic response, and only three underwent UD-CBT within 1 year of diagnosis. After serological typing for class I antigens, and high-resolution DNA typing for DRB1, the degree of HLA match between patients and cord blood (CB) units was 4/6 in six cases and 5/6 in three cases. The median number of nucleated cells infused was 1.7 × 107/kg (range, 1.2 to 4.9 × 107/kg), and was above 2 × 107/kg in only two cases. All patients received thiotepa, busulfan, cyclophosphamide and anti-thymocyte globulin as conditioning; cyclosporine and prednisone for graft-versus-host disease (GVHD) prophylaxis; and G-CSF from day +7 until engraftment. All seven evaluable cases engrafted. The median time to reach an absolute neutrophil count ⩾0.5 × 109/l and ⩾1 × 109/l was 22 days (range, 19–52 days) and 28 days (range, 23–64 days), respectively. In the four patients evaluable for platelet recovery time to levels of ⩾20 × 109 platelets/l, ⩾50 × 109 platelets/l, and ⩾100 × 109 platelets/l, these ranged from 50 to 128 days, 60 to 139 days, and 105 to 167 days, respectively. Three patients developed acute GVHD above grade II, and three of the five patients at risk developed extensive chronic GVHD. Four patients, all transplanted in chronic phase, remain alive in molecular remission more than 18, 19, 24 and 42 months after transplantation. These preliminary results suggest that UD-CBT may be considered a reasonable alternative in adults with CML who lack an appropriate bone marrow donor. Bone Marrow Transplantation (2001) 27, 693–701.

High-resolution melting analysis for rapid screening of BRCA1 and BRCA2 Spanish mutations

The majority of BRCA1 and BRCA2 mutation detection procedures include screening methods, all of which are time-consuming. High-resolution melting (HRM) is a promising pre-screening method of gene scanning that combines simplicity and rapid identification of genetic variants. We evaluated HRM in the screening of BRCA1/2 Spanish mutations. We studied 40 BRCA1 and 47 BRCA2 DNA samples with different Spanish mutations. We included a group of 20 unknown DNAs from patients with sporadic breast cancer (BC). The assay was performed with the LightCycler® 480 Instrument (Roche). The HRM discriminates all the BRCA1/2 Spanish mutations studied from wild-type DNA. Besides, 54 out of 87 mutations were clearly differentiated from each other. In sporadic BC 11 polymorphisms and three unclassified variants were found in both genes. HRM is a valuable method for rapid screening of BRCA1/2 Spanish mutations and is capable of differentiating new genetic variants in PCR products.

Prognostic value of FLT3 mutations in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline monochemotherapy

Background Fms-like tyrosine kinase-3 (FLT3) gene mutations are frequent in acute promyelocytic leukemia but their prognostic value is not well established. Design and Methods We evaluated FLT3-internal tandem duplication and FLT3-D835 mutations in patients treated with all-trans retinoic acid and anthracycline-based chemotherapy enrolled in two subsequent trials of the Programa de Estudio y Tratamiento de las Hemopatías Malignas (PETHEMA) and Hemato-Oncologie voor Volwassenen Nederland (HOVON) groups between 1996 and 2005. Results FLT3-internal tandem duplication and FLT3-D835 mutation status was available for 306 (41%) and 213 (29%) patients, respectively. Sixty-eight (22%) and 20 (9%) patients had internal tandem duplication and D835 mutations, respectively. Internal tandem duplication was correlated with higher white blood cell and blast counts, lactate dehydrogenase, relapse-risk score, fever, hemorrhage, coagulopathy, BCR3 isoform, M3 variant subtype, and expression of CD2, CD34, human leukocyte antigen-DR, and CD11b surface antigens. The FLT3-D835 mutation was not significantly associated with any clinical or biological characteristic. Univariate analysis showed higher relapse and lower survival rates in patients with a FLT3-internal tandem duplication, while no impact was observed in relation to FLT3-D835. The prognostic value of the FLT3-internal tandem duplication was not retained in the multivariate analysis. Conclusions FLT3-internal tandem duplication mutations are associated with several hematologic features in acute promyelocytic leukemia, in particular with high white blood cell counts, but we were unable to demonstrate an independent prognostic value in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline-based regimens.

Prolonged molecular remission after PML/RARα-positive autologous peripheral blood stem cell transplantation in acute promyelocytic leukemia: is relevant pretransplant minimal residual disease in the graft?

The contribution of residual malignant cells contaminating the autologous graft with the occurrence of post-transplant relapse in acute myeloid leukemia (AML) is still unclear. The presence of a specific molecular marker (the PML/RARα rearrangement) in acute promyelocytic leukemia (APL) offers the opportunity to investigate better the pathogenesis of disease recurrence after transplant. We report an APL patient who received high-dose chemotherapy and peripheral blood stem cell (PBSC) autograft in second hematologic remission. Two leukaphereses that tested PML/RARα positive by RT-PCR were obtained during the post-reinduction hematopoietic recovery, while the patient also tested PCR positive in the BM, and was reinfused after myeloablative chemotherapy (BUCY4), when the patient had spontaneously converted to PCR negative in the marrow. At present, he remains in continuous molecular and hematologic remission 22 months after PBSC transplantation. This is the second report of an APL patient who was transplanted in molecular remission with a PML/RARα-positive PBSC autograft. As in the previous report, the prolonged clinical and molecular remission experienced post-transplant suggests that autologous PBSC infusion is still worthy of consideration for patients with APL in spite of the detection of PML/RARα-positive cells in the PBSC collections. Possible underlying mechanisms and the potential role of molecular monitoring of the graft, as well as the host, before and after transplant, in patients with APL undergoing autologous HSCT are also discussed.

A novel NUP98/RARG gene fusion in acute myeloid leukemia resembling acute promyelocytic leukemia

Chromosomal translocations in hematological malignancies often result in novel fusion chimeric genes. We report a case of acute myeloid leukemia with a clonal translocation t(11;12)(p15;q13) displaying morphologic and immunophenotypic features resembling the classical hypergranular subtype of acute promyelocytic leukemia. The gene fused to NUP98 (nucleoporin 98) was detected by comparative genomic hybridization array as the retinoid acid receptor gamma gene (RARG). The involvement of RARG in a chimeric fusion transcript has not been reported previously in human leukemia.

Minimal residual disease detection in acute myeloid leukemia by mutant nucleophosmin (NPM1) : Comparison with WT1 gene expression

BACKGROUND Molecular analysis of minimal residual disease is only applicable in acute myeloblastic leukemia (AML) patients with genetic markers (20-30%). This study analyzes the feasibility of the real-time quantitative polymerase chain reaction (RQ-PCR) assay to detect mutant nucleophosmin (NPM1) during follow-up in AML patients. Moreover, we compare the NPM1 results with those of WT1 expression to MRD assessment. METHODS The study includes 97 samples from 24 AML patients with type A NPM1 mutation at diagnosis. MRD was evaluated simultaneous by RQ-PCR assay to detect NPM1-mutated and WT1 expression. RESULTS The expression levels of WT1 and NPM1 in 93 paired samples showed a strong positive correlation (r=0.81; p<0.0001). However, the kinetics of disappearance were different, WT1 decreased rapidly after induction but maintained these residual levels after treatment in patients in complete remission, whereas NPM1 experienced a mild reduction after induction but was undetectable in long survivor patients. CONCLUSIONS This study shows the feasibility of the RQ-PCR assay to monitor MRD in AML patients carrying NPM1 mutations and its advantage over RQ-PCR assay for WT1. Owing to NPM1-mutated is specific of leukemic cells and shows higher levels at presentation.