A multicenter total therapy strategy for de novo adult Philadelphia chromosome positive acute lymphoblastic leukemia patients: final results of the GIMEMA LAL1509 protocol.

The GIMEMA LAL1509 protocol, designed for adult (≥18-60 years) de novo Ph+ acute lymphoblastic leukemia patients, was based on a dasatinib plus steroids induction - with central nervous system prophylaxis - followed by dasatinib alone in patients in complete molecular response or chemotherapy and/or allogeneic transplantation in patients not reaching a complete molecular response. Sixty patients (median age 41.9 years) were enrolled: 33 were p190+, 18 p210+ and 9 p190/p210+. At the end of induction (day +85), 58 patients (97%) achieved a complete hematologic remission. No deaths in induction were recorded. Eleven patients (18.3%) obtained a complete molecular response. Among non-complete molecular responders (n=47), 22 underwent an allogeneic transplant. Seventeen hematologic relapses occurred (median 7 months, range 3-40.1), 13 during consolidation and 4 post-transplant. ABL1 mutations (5 T315I, 3 V299L, 1 E281K and 1 G254E) were found in 10/13 relapsed cases. With a median follow-up of 57.4 months (range: 4.2-75.6), overall survival and disease-free survival are 56.3% and 47.2%. A better diseasefree survival was observed in patients who obtained a molecular response at day +85 compared to cases who did not. The presence of additional copy number aberrations - IKZF1 plus CDKN2A/B and/or PAX5 deletions - was the most important unfavorable prognostic factor on overall and disease-free survival (p=0.005 and p=0.0008). This study shows that in adult Ph+ ALL long-term survivals can be achieved with a total-therapy strategy based on a chemo-free induction and, in complete molecular responders, also without further systemic chemotherapy. Finally, the screening of additional copy number aberrations should be included in the diagnostic work-up. EudraCT 2010-019119-39.

Correction: Gene expression, proteome and calcium signaling alterations in immortalized hippocampal astrocytes from an Alzheimer's disease mouse model.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Gene expression, proteome and calcium signaling alterations in immortalized hippocampal astrocytes from an Alzheimer's disease mouse model.

Evidence is rapidly growing regarding a role of astroglial cells in the pathogenesis of Alzheimer's disease (AD), and the hippocampus is one of the important brain regions affected in AD. While primary astroglial cultures, both from wild-type mice and from rodent models of AD, have been useful for studying astrocyte-specific alterations, the limited cell number and short primary culture lifetime have limited the use of primary hippocampal astrocytes. To overcome these limitations, we have now established immortalized astroglial cell lines from the hippocampus of 3xTg-AD and wild-type control mice (3Tg-iAstro and WT-iAstro, respectively). Both 3Tg-iAstro and WT-iAstro maintain an astroglial phenotype and markers (glutamine synthetase, aldehyde dehydrogenase 1 family member L1 and aquaporin-4) but display proliferative potential until at least passage 25. Furthermore, these cell lines maintain the potassium inward rectifying (Kir) current and present transcriptional and proteomic profiles compatible with primary astrocytes. Importantly, differences between the 3Tg-iAstro and WT-iAstro cell lines in terms of calcium signaling and in terms of transcriptional changes can be re-conducted to the changes previously reported in primary astroglial cells. To illustrate the versatility of this model we performed shotgun mass spectrometry proteomic analysis and found that proteins related to RNA binding and ribosome are differentially expressed in 3Tg-iAstro vs WT-iAstro. In summary, we present here immortalized hippocampal astrocytes from WT and 3xTg-AD mice that might be a useful model to speed up research on the role of astrocytes in AD.

Genetic risk of prediabetes and diabetes development in chronic myeloid leukemia patients treated with nilotinib.

Impaired fasting glucose and type 2 diabetes represent adverse events in patients with chronic myeloid leukemia (CML) treated with the second generation tyrosine kinase inhibitor nilotinib. An unweighted genetic risk score (uGRS) for the prediction of insulin resistance, consisting of 10 multiple single-nucleotide polymorphisms, has been proposed. We evaluated uGRS predictivity in 61 CML patients treated with nilotinib. Patients were genotyped for IRS1, GRB14, ARL15, PPARG, PEPD, ANKRD55/MAP3K1, PDGFC, LYPLAL1, RSPO3, and FAM13A1 genes. The uGRS was based on the sum of the risk alleles within the set of selected single-nucleotide polymorphisms. Molecular response (MR)3.0 and MR4.0 were achieved in 90% and 79% of patients, respectively. Before treatment, none of the patients had abnormal blood glucose. During treatment and subsequent follow-up at 80.2 months (range: 1-298), seven patients (11.5%) had developed diabetes that required oral treatment, a median of 14 months (range: 3-98) after starting nilotinib treatment. Twelve patients (19.7%) had developed prediabetes. Prediabetes/diabetes-free survival was significantly higher in patients with a uGRS <10 than in those with higher scores (100% vs. 22.8 ± 12.4%, p <0.001). Each increment of one unit in the uGRS caused a 42% increase in the prediabetes/diabetes risk (hazard ratio = 1.42, confidence interval: 1.04-1.94, p = 0.026). The presence of more than 10 allelic variants associated with insulin secretion, processing, sensitivity, and clearance is predictive of prediabetes/diabetes development in CML patients treated with nilotinib. In clinical practice, uGRS could help tailor the best tyrosine kinase inhibitor therapy.

Clinical relevance of hypogammaglobulinemia, clinical and biologic variables on the infection risk and outcome of patients with stage A chronic lymphocytic leukemia.

The prognostic effect of hypogammaglobulinemia (HGG), clinical and biologic characteristics on the infection risk and outcome has been retrospectively analyzed in 899 patients with stage A chronic lymphocytic leukemia (CLL). Low levels of IgG were recorded in 19.9% of patients at presentation, low levels of IgM and/or IgA in 10.4% and an additional 20% of patients developed HGG during the course of the disease. Before the start of any treatment, 160 (12.9%) patients experienced at least one grade ≥3 infection requiring a systemic anti-infective treatment and/or hospitalization. While IgG levels at diagnosis were not associated with an increased risk of grade ≥3 infection or with an adverse outcome, a significantly increased rate of grade ≥3 infections was recorded in patients with unmutated IGHV (p=0.011) and unfavorable FISH aberrations (p=0.009). Late onset HGG, more frequently recorded in patients with Rai stage I-II (p=0.001) and unmutated IGHV (p=0.001), was also associated with a higher rate of severe infections (p=0.002). These data indicate that, stage A patients with clinical and biologic characteristics of a more aggressive disease develop more frequently late onset HGG, grade ≥3 infections and require a closer clinical monitoring.

A sequential approach with imatinib, chemotherapy and transplant for adult Ph+ acute lymphoblastic leukemia: final results of the GIMEMA LAL 0904 study.

In the GIMEMA LAL 0904 protocol, adult Philadelphia positive acute lymphoblastic leukemia patients were treated with chemotherapy for induction and consolidation, followed by maintenance with imatinib. The protocol was subsequently amended and imatinib was incorporated in the induction and post-remission phase together with chemotherapy. Due to the toxicity of this combined approach, the protocol was further amended to a sequential scheme based on imatinib plus steroids as induction, followed by consolidation with chemotherapy plus imatinib and, when applicable, by a hematopoietic stem cell transplant. Fifty-one patients (median age 45.9 years) were enrolled in the final sequential protocol. At the end of induction (day +50), 96% of evaluable patients (n=49) achieved a complete hematologic remission; after consolidation, all were in complete hematologic remission. No deaths in induction were recorded. Overall survival and disease-free survival at 60 months are 48.8% and 45.8%, respectively. At day +50 (end of imatinib induction), a more than 1.3 log-reduction of BCR-ABL1 levels was associated with a significantly longer disease-free survival (55.6%, 95%CI: 39.0-79.3 vs. 20%, 95%CI: 5.8-69.1; P=0.03), overall survival (59.1%, 95%CI: 42.3-82.6 vs. 20%, 95%CI: 5.8-69.1; P=0.02) and lower incidence of relapse (20.5%, 95%CI: 7.2-38.6 vs. 60.0%, 95%CI: 21.6-84.3; P=0.01). Mean BCR-ABL1 levels remained significantly higher in patients who subsequently relapsed. Finally, BCR-ABL1p190 patients showed a significantly faster molecular response than BCR-ABL1p210 patients (P=0.023). Though the study was not powered to evaluate the role of allogeneic stem cell transplant, allografting positively impacted on both overall and disease-free survival. In conclusion, a sequential approach with imatinib alone in induction, consolidated by chemotherapy plus imatinib followed by a stem cell transplant is a feasible, well-tolerated and effective strategy for adult Philadelphia positive acute lymphoblastic leukemia, leading to the best long-term survival rates so far reported. (clinicaltrials.gov identifier: 00458848).

CRLF2 overexpression identifies an unfavourable subgroup of adult B-cell precursor acute lymphoblastic leukemia lacking recurrent genetic abnormalities.

BACKGROUND: A deregulated CRLF2 (d-CRLF2) expression was described in B-cell acute lymphoblastic leukemia without recurrent fusion genes (B-NEG ALL). While the role of d-CRLF2 in children has been extensively described, little is known about its role and impact in adult ALL. METHODS: Expression levels of CRLF2 were evaluated by quantitative real-time PCR in 102 newly-diagnosed adult B-NEG ALL and correlated with the clinico-biological characteristics and outcome. Incidence and clinical impact of the P2RY8/CRLF2 transcript was also assessed. RESULTS: High CRLF2 levels, as continuous variable, were significantly associated with hyperleucocytosis (p=0.0002) and thrombocytopenia (p=0.005); when a cut-point at ΔCt≤8 was applied, 35 cases (34.3%), mostly males (80%), proved positive for CRLF2 expression. High CRLF2 levels, as continuous or categorical variable, were associated with a worse disease-free (p=0.003 and p=0.015) and overall survival (p=0.017 and 0.0038). Furthermore, when CRLF2 was analyzed as a categorical variable, a high statistical association was found with IKZF1 deletion and mutations in the JAK/STAT pathway (p=0.001 and p<0.0001, respectively). Finally, the P2RY8/CRLF2 transcript, identified in 8/102 patients (7.8%), was associated with a poor outcome. CONCLUSIONS: In adult B-NEG ALL, high CRLF2 expression is associated with distinct clinico-biological features and an unfavourable prognosis in both univariate and multivariate analysis; similarly, P2RY8/CRLF2 positivity correlates with a poor outcome. The quantification of CRLF2 is an important prognostic marker in adult B-lineage ALL without known genetic lesions.

Early lenalidomide treatment for low and intermediate-1 International Prognostic Scoring System risk myelodysplastic syndromes with del(5q) before transfusion dependence.

Lenalidomide is approved for the treatment of transfusion-dependent (TD) del(5q) myelodysplastic syndromes (MDS). However, few data are available in patients with transfusion-independent (TI) del(5q) MDS. In the first, observational, part of this 2-part study, we assessed the impact of transfusion dependence on overall survival (OS) and non-leukemic death in untreated del(5q) MDS patients who were TD (n = 136), TI with hemoglobin (Hb) ≥10 mg/dL (n = 88), or TI with Hb <10 mg/dL (n = 96). In the second, interventional, part we assessed the quality-of-life (QoL) benefits and clinical efficacy of lenalidomide (10 mg/day) in 12 patients with TI del(5q) MDS and Hb <10 mg/dL. In the untreated population, OS was significantly longer in TI than in TD patients (TI [Hb ≥10 g/dL], 108 months; TI [Hb <10 g/dL], 77 months; TD, 44 months). Transfusion dependence also negatively impacted non-leukemic death rates. In the interventional part of the study, baseline Hb levels were found to correlate significantly with physical (R = 0.666, P = 0.035) and fatigue (R = 0.604, P = 0.049) QoL scores. Median physical QoL scores improved significantly after 12 weeks' treatment with lenalidomide (+12.5; P = 0.020). Evaluable TI patients experienced early increases in Hb levels, and all attained an erythroid response. Our findings suggest that TI patients with moderate anemia may benefit from early treatment with lenalidomide.

Efficacy of biosimilar granulocyte colony-stimulating factor versus originator granulocyte colony-stimulating factor in peripheral blood stem cell mobilization in de novo multiple myeloma patients.

BACKGROUND AIMS: Filgrastim and lenograstim are the standard granulocyte colony-stimulating factor (G-CSF) agents for peripheral blood stem cell mobilization (PBSC) in patients who undergo autologous stem cell transplantation. METHODS: To assess whether biosimilars are effective, we conducted a single-center, prospective study that included 40 consecutive de novo multiple myeloma patients who received cyclophosphamide 4 g/m(2) per day plus biosimilar filgrastim G-CSF to mobilize PBSC. These patients were compared with a group of 37 patients matched for age, diagnosis, previous chemotherapy and mobilization who had been treated with originator G-CSF. The mean number of CD34+ cells/µL in the peripheral blood was 199.6 ± 207.4 in the biosimilar and 192.8 ± 154.7 in the originator group (P = 0.87). The median number of CD34+ cells/kg recipient collected was 11.5 ± 5.8 and 12.3 ± 5.3 in the biosimilar and originator groups, respectively (P = 0.51). The mobilization failure rate was 2.5% and 2.7% in the biosimilar filgrastim and originator filgrastim cohorts (P = NS), respectively. RESULTS: Twenty-nine patients in the biosimilar group and 28 patients in the originator group underwent autologous transplantation. There were no statistically significant differences between the biosimilar and originator G-CSF cohorts in terms of hematopoietic recovery parameters and transplant-related toxicities. CONCLUSIONS: The efficacy of biosimilar G-CSF appears to be equivalent to the reference G-CSF.

Tolerability and efficacy of busulfan and fludarabine as allogeneic pretransplant conditioning therapy in acute myeloid leukemia: comparison with busulfan and cyclophosphamide regimen.

BACKGROUND: The aim of this study was to compare safety and efficacy of the association of busulfan with cyclophosphamide (BuCy2) versus busulfan and fludarabine (BuFlu) as a conditioning regimen in allogeneic hematopoietic progenitor cell transplantation (allo-HPCT) in patients with acute myeloid leukemia (AML). PATIENTS AND METHODS: A total of 65 consecutive patients who received an allo-HPCT from Human Leucocyte Antigen-matched sibling donors were analyzed. The conditioning was BuCy2 in 48 patients and BuFlu in 17 patients. RESULTS: There were no significant differences between the 2 cohorts in hematological engraftment, incidence of extrahematological toxicities, and acute graft versus host disease (GVHD). The incidence of chronic GVHD was 34% in the BuCy2 group versus 57% in the BuFlu group (P = .03). Transplant-related mortality was 17% (8 patients) in the BuCy2 group versus 0 in the BuFlu arm. Disease-related mortality was similar in the whole study population; in high-risk AML patients it was 11% in the BuCy2 group and 19% in the BuFlu group (P = .015). The probability of disease-free and event-free survival at 2 years was, respectively, 70% and 60% in the BuCy2 group and 59% and 58% in the BuFlu group (P = .06 and P = not significant [ns]). The probability of overall survival at 2 years was 71% in the BuCy2 group and 63% in the BuFlu group (P = ns), and in the high-risk group it was 83% and 67% in the BuCy2 and BuFlu group, respectively (P = ns). CONCLUSION: BuFlu is well tolerated and is less toxic than BuCy2 and our results did not suggest that in high-risk AML, BuCy2 should be the favorite regimen in terms of efficacy.

Long-term results in multiple myeloma after high-dose melphalan and autologous transplantation according to response categories in the era of old drugs.

BACKGROUND: The aim of this study was to investigate the correlation between the long-term prognosis of multiple myeloma (MM) and the quality of response to therapy in a cohort of 173 patients treated with high-dose melphalan (HDM) and autologous transplantation in the era of old drugs. PATIENTS AND METHODS: A total of 173 patients with de novo MM who received a transplant between 1994 and 2010 were analyzed. VAD (vincristine, doxorubicin [Adriamycin], dexamethasone) was used as front-line regimen before auto-HPCT. The conditioning was HDM 200 mg/m(2). Patients were evaluated for clinical response using the criteria from the European Group for Blood and Marrow Transplantation, modified to include near complete remission (nCR) and very good partial remission (VGPR). RESULTS: The response distribution after transplantation in our series was complete remission (CR) in 33 cases (19%), nearly complete remission (nCR) in 38 cases (22%), VGPR in 30 cases (17%), partial remission (PR) in 65 cases (38%), and stable disease (SD) in 7 cases (4%). Patients were followed for 48 ± 36 months. Median overall survival (OS) was not reached for the CR group. Progression-free survival (PFS) was 122 months for CR, 55 months for nCR, 56 months for VGPR, 32 months for PR, and 22 months for SD. Significant differences in PFS and OS were found between the CR and nCR groups (P = .003 and P = .001, respectively), between the CR and VGPR groups (P = .002 and P = .001, respectively), and between the CR and PR groups (P = .000 and P = .001, respectively). Responses were clustered in 3 main categories, ie, CR, nCR + VGPR + PR, and SD. The respective 10-year PFS and OS values were 58% and 70% for CR, 15% and 18% for nCR + VGPR + PR, and 0% and 0% for SD. CONCLUSION: The achievement of depth and prolonged response represents the most important prognostic factor. The relapse rate is low for patients in CR after 10 years of follow-up, possibly signifying a cure.

Optimizing outcomes following allogeneic hematopoietic progenitor cell transplantation in AML: the role of hypomethylating agents.

Aberrant DNA methylation is a key pathological mechanism in myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML), and provides rationale for the clinical development of hypomethylating agents (HMAs) for the treatment of these diseases. One HMA, azacitidine (Vidaza®, Celgene Corp.), has demonstrated improved survival versus conventional care regimens in patients with intermediate-2/high-risk MDS and AML (20-30% blasts) and has a favorable tolerability profile. Emerging evidence indicates that azacitidine can have an immunomodulatory effect by, for example, increasing functional regulatory T-cell (Treg) numbers and killer-cell-immunoglobulin-like receptor expression. Allogeneic hematopoietic progenitor cell transplantation (allo HPCT) is the only potentially curative treatment approach in patients with advanced MDS or AML. Unfortunately, allo HPCT in these settings is limited because most patients are ineligible due to age/comorbidities, or are at a high risk of treatment failure due to disease relapse. Recent studies have shown that azacitidine after allo HPCT increases Treg numbers while inducing a cytotoxic CD8+ T-cell response, suggesting a potential mechanism for augmenting the graft-versus-leukemia (GvL) effect without increasing graft-versushost- disease (GVHD). In patients at a high risk of relapse following allo HPCT, pre-emptive azacitidine may help prevent/delay relapse. For patients who have relapsed following allo HPCT, azacitidine may be a salvage therapy option, either as monotherapy or in combination with donor lymphocyte infusions (DLI). In this mini-review, we discuss these emerging clinical data for HMAs in the post-allo HPCT regimens and highlight the possible future role of azacitidine in this setting.

Quality of life in elderly patients with acute myeloid leukemia: patients may be more accurate than physicians.

BACKGROUND: The aim of this study was to evaluate changes in quality of life scores and their association with therapy and survival in unselected elderly patients with acute myeloid leukemia. DESIGN AND METHODS: From February 2003 to February 2007, 113 patients aged more than 60 years with de novo acute myeloid leukemia were enrolled in a prospective observational study. Two different quality of life instruments were employed: the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire - C30 (EORTC QLQ-C30) and a health-related quality of life questionnaire for patients with hematologic diseases (QOL-E). RESULTS: Forty-eight patients (42.4%) received intensive chemotherapy and 65 (57.6%) were given palliative treatments. Age greater than 70 years (P=0.007) and concomitant diseases (P=0.019) had a significant impact on treatment allocation. At diagnosis, general quality of life was affected [median QOL-E standardized score 54, interquartile range 46-70; median EORTC global score 50, interquartile range 41-66]. Most patients were given a good ECOG Performance Status (< 2), which did not correlate with the patients' perception of quality of life. At multivariate analysis, palliative approaches (P=0.016), age more than 70 years (P=0.013) and concomitant diseases (P=0.035) each had an independent negative impact on survival. In a multivariate model corrected for age, concomitant diseases and treatment option, survival was independently predicted by QOL-E functional (P=0.002) and EORTC QLQ-C30 physical function (P=0.030) scores. CONCLUSIONS: Quality of life could have an important role in elderly acute myeloid leukemia patients at diagnosis as a prognostic factor for survival and a potential factor for treatment decisions.

Changes in RPS14 expression levels during lenalidomide treatment in Low- and Intermediate-1-risk myelodysplastic syndromes with chromosome 5q deletion.

BACKGROUND: Haploinsufficiency of the ribosomal protein S14 RPS14 gene, located in the common deleted region of chromosome 5q, is a potential causal factor of 5q- syndrome. Lenalidomide elicits high response rates and morphological improvements in myelodysplastic syndrome (MDS) patients with chromosome 5q deletion [del(5q)]. METHODS: To further evaluate the role of RPS14, its transcription was tested in bone marrow cells from 17 patients with International Prognostic Scoring System defined Low- or Intermediate-1-risk MDS with del(5q) as a single or additional cytogenetic abnormality receiving treatment with lenalidomide. RESULTS: After 12 wk of lenalidomide treatment, erythroid responses were observed in all cases with an increase in hemoglobin levels of 2.7 +/- 2.5 g/dL (up to a mean 11.8 +/- 1.9 g/dL; P = 0.001). Before treatment, RPS14 expression levels were under-expressed in 15 patients with respect to normal controls. After 12 wk of lenalidomide treatment, all patients had an erythroid response. There was a significant increase in median RPS14 expression from baseline 0.01 (IQR 0.05-0.31) to 12 wk 204.71-fold (2.86-446.32; P < 0.0001). CONCLUSIONS: These observations in the patient setting support the importance of RPS14 in the pathogenesis of MDS with del(5q).

Darbepoetin alfa for the treatment of anemia associated with myelodysplastic syndromes: efficacy and quality of life.

To evaluate efficacy, safety, changes in biological features, and quality of life (QoL) in low-risk anemic patients with MDS treated with darbepoetin alfa (DPO), 41 patients received DPO 150 microg weekly for 24 weeks. The dose was increased to 300 microg weekly in non-responsive patients. During treatment, 10/17 (59%) transfusion-dependent (TD) and 13/23 (56%) transfusion-free (TF) patients responded. In TF patients, Hb increased from 9.2 +/- 0.9 g/dL to 10.3 +/- 1.4 g/dL by 24 weeks (p = 0.004). The mean response duration was 22 weeks (95% CI: 19.7-24.0) in TF patients compared with 15.1 weeks (95% CI: 13.3-17.5) in TD patients. Response to treatment was associated with increases in QoL. Decreases in the percentage of apoptotic progenitor cells (p = 0.007) and CD34+ cells (p = 0.005) were observed. These results confirm previous studies demonstrating the safety and efficacy of DPO in anemic patients with MDS. Biological changes and improvement in QoL were associated with response. Adequate dosing is to be determined.

Iron chelation therapy associated with improvement of hematopoiesis in transfusion-dependent patients.

BACKGROUND: It is well known that iron overload may cause multiple organ failure. In chronically transfused patients, optimal iron chelation therapy is associated with reduced morbidity and mortality. Furthermore, chelation therapy has been associated with erythroid responses. STUDY DESIGN AND METHODS: Among chronically transfused adults affected by myeloproliferative neoplasms and treated with iron chelators, two case reports are described. CASE REPORT: A male adult patient with myelodysplastic syndrome (MDS) and a female adult with aplastic anemia (AA), both transfusion-dependent, were treated with deferasirox, an oral iron chelator. RESULTS: A significant reduction in transfusion requirement was observed and was dependent on chelation therapy. The patient affected by AA also experienced a significant increase in hemoglobin levels. Minimal doses of deferasirox maintained the erythroid responses. Many mechanisms of action of the drug on erythropoiesis have been postulated. The early erythroid response seems to be independent of the removal of iron from deposits, per se, since the reduction of ferritin levels (a surrogate marker of iron deposits) below threshold levels occurs as a later event. CONCLUSION: Although there are few reports on erythroid responses in patients undergoing iron chelation therapy, they may give new insights in the pathogenesis of MDS and other myeloproliferative neoplasms. AA may benefit in terms of erythroid response. The findings in these cases underline the clinical importance of treating patients with iron overload. A survival benefit of chelation in patients with myeloproliferative neoplasms is still to be confirmed.

ERK1/2 phosphorylation is an independent predictor of complete remission in newly diagnosed adult acute lymphoblastic leukemia.

Extracellular signal-regulated kinase-1/2 (ERK1/2) is frequently found constitutively activated (p-ERK1/2) in hematopoietic diseases, suggesting a role in leukemogenesis. The aim of this study was to assess the expression and clinical role of p-ERK1/2 in adult acute lymphoblastic leukemia (ALL). In 131 primary samples from adult de novo ALL patients enrolled in the Gruppo Italiano per le Malattie Ematologiche dell'Adulto (GIMEMA) Leucemia Acute Linfoide (LAL) 2000 protocol and evaluated by flow cytometry, constitutive ERK1/2 activation was found in 34.5% of cases; these results were significantly associated with higher white blood cell (WBC) values (P=.013). In a multivariate analysis, p-ERK1/2 expression was an independent predictor of complete remission achievement (P=.027). Effective approaches toward MEK inhibition need to be explored in order to evaluate whether this may represent a new therapeutic strategy for adult ALL patients.