The Addition of All-Trans Retinoic Acid to Chemotherapy May Not Improve the Outcome of Patient with NPM1 Mutated Acute Myeloid Leukemia.

BACKGROUND: Previous studies have suggested that NPM1 mutations may be a marker for response to all-trans retinoic acid (ATRA) given as an adjunct to intensive chemotherapy in older patients with acute myeloid leukemia (AML). PATIENTS AND METHODS: We examined the impact of the addition of ATRA among patients with diploid cytogenetics treated on a randomized phase II study of fludarabine + cytarabine + idarubicine ± G-CSF ± ATRA with available data on their NPM1 mutation status. Between September 1995 and November 1997, 215 patients were enrolled in the study. Among them, 70 patients had diploid cytogenetic and are the subjects of this analysis. RESULTS: The median age of the 70 patients was 66 years (range 23-87). Twenty (29%) of patients had NPM1 mutations. Among them 7 (35%) did and 13 (65%) did not receive ATRA in combination with chemotherapy. Complete remission (CR) was achieved in 71% of patients treated with ATRA as compared to 69% without ATRA (P = 0.62). With median follow-up of 12.5 years, the overall survival (OS), event-free survival (EFS), and relapse-free survival (RFS) were similar among patients who received ATRA compared to no ATRA regardless of NPM1 mutation status. CONCLUSION: The addition of ATRA to intensive chemotherapy did not affect the overall outcome of patients with AML regardless of NPM1 mutation status.

Over-expression of CYP2E1 mRNA and protein: implications of xenobiotic induced damage in patients with de novo acute myeloid leukemia with inv(16)(p13.1q22); CBFß-MYH11.

Environmental exposure to benzene occurs through cigarette smoke, unleaded gasoline and certain types of plastic. Benzene is converted to hematotoxic metabolites by the hepatic phase-I enzyme CYP2E1, and these metabolites are detoxified by the phase-II enzyme NQO1. The genes encoding these enzymes are highly polymorphic and studies of these polymorphisms have shown different pathogenic and prognostic features in various hematological malignancies. The potential role of different cytochrome p450 metabolizing enzymes in the pathogenesis of acute myeloid leukemia (AML) in an area of active interest. In this study, we demonstrate aberrant CYP2E1 mRNA over-expression by quantitative real-time polymerase chain reaction in 11 cases of de novo AML with inv(16); CBFß-MYH11. CYP2E1 mRNA levels correlated with CBFß-MYH11 transcript levels and with bone marrow blast counts in all cases. CYP2E1 over-expression correlated positively with NQO1 mRNA levels (R(2) = 0.934, n = 7). By immunohistochemistry, CYP2E1 protein was more frequently expressed in AML with inv(16) compared with other types of AML (p < 0.001). We obtained serial bone marrow samples from two patients with AML with inv(16) before and after treatment. CYP2E1 mRNA expression levels decreased in parallel with CBFß-MYH11 transcript levels and blast counts following chemotherapy. In contrast, CYP1A2 transcript levels did not change in either patient. This is the first study to demonstrate concurrent over-expression of CYP2E1 and NQO1 mRNA in AML with inv(16). These findings also suggest that a balance between CYP2E1 and NQO1 may be important in the pathogenesis of AML with inv(16).

Circulating microRNAs let-7a and miR-16 predict progression-free survival and overall survival in patients with myelodysplastic syndrome.

Circulating microRNAs (miRNAs) are potential biomarkers for cancer. We examined plasma levels of 2 miRNAs, let-7a and miR-16, in 50 patients with myelodysplastic syndrome (MDS) and 76 healthy persons using quantitative real-time PCR. Circulating levels of both miRNAs were similar among healthy controls but were significantly lower in MDS patients (P = .001 and P < .001, respectively). The distributions of these 2 miRNA levels were bimodal in MDS patients, and these levels were significantly associated with their progression-free survival and overall survival (both P < .001 for let-7a; P < .001 and P = .001 for miR-16). This association persisted even after patients were stratified according to the International Prognostic Scoring System. Multivariate analysis revealed that let-7a level was a strong independent predictor for overall survival in this patient cohort. These findings suggest that let-7a and miR-16 plasma levels can serve as noninvasive prognostic markers in MDS patients.

MicroRNA fingerprints identify miR-150 as a plasma prognostic marker in patients with sepsis.

BACKGROUND: The physiopathology of sepsis continues to be poorly understood, and despite recent advances in its management, sepsis is still a life-threatening condition with a poor outcome. If new diagnostic markers related to sepsis pathogenesis will be identified, new specific therapies might be developed and mortality reduced. Small regulatory non-coding RNAs, microRNAs (miRNAs), were recently linked to various diseases; the aim of our prospective study was to identify miRNAs that can differentiate patients with early-stage sepsis from healthy controls and to determine if miRNA levels correlate with the severity assessed by the Sequential Organ Failure Assessment (SOFA) score. METHODOLOGY/PRINCIPAL FINDINGS: By using genome-wide miRNA profiling by microarray in peripheral blood leukocytes, we found that miR-150, miR-182, miR-342-5p, and miR-486 expression profiles differentiated sepsis patients from healthy controls. We also proved by quantitative reverse transcription-polymerase chain reaction that miR-150 levels were significantly reduced in plasma samples of sepsis patients and correlated with the level of disease severity measured by the SOFA score, but were independent of the white blood counts (WBC). We found that plasma levels of tumor necrosis factor alpha, interleukin-10, and interleukin-18, all genes with sequence complementarity to miR-150, were negatively correlated with the plasma levels of this miRNA. Furthermore, we identified that the plasma levels ratio for miR-150/interleukin-18 can be used for assessing the severity of the sepsis. CONCLUSIONS/SIGNIFICANCE: We propose that miR-150 levels in both leukocytes and plasma correlate with the aggressiveness of sepsis and can be used as a marker of early sepsis. Furthermore, we envision miR-150 restoration as a future therapeutic option in sepsis patients.

Analysis of Aurora kinase A expression in CD34(+) blast cells isolated from patients with myelodysplastic syndromes and acute myeloid leukemia.

Aurora kinase A, also known as aurora A, is a serine/threonine kinase that plays critical roles in mitosis entry, chromosome alignment, segregation, and cytokinesis. Overexpression of aurora A has been observed in many solid tumors and some hematopoietic neoplasms, but little is known about its expression in myeloid diseases. Because cytogenetic abnormalities play an essential role in the pathogenesis of myeloid malignancies, we hypothesized that aurora A deregulation may be involved in myelodysplastic syndromes and acute myeloid leukemia and contribute to the chromosomal instability observed in these diseases. We assessed aurora A mRNA levels in CD34(+) bone marrow blasts from nine patients with acute myeloid leukemia, 20 patients with myelodysplastic syndromes, and five normal patients serving as controls. CD34(+) blasts were isolated from bone marrow aspirate specimens using magnetic activated cell separation technology. RNA was extracted from purified CD34(+) cells, and quantitative real-time reverse transcriptase polymerase chain reaction for aurora A was performed. Immunocytochemical analyses for total aurora A, phosphorylated aurora A, Ki-67, and activated caspase 3 were performed on cytospin slides made from purified CD34(+) cells in myelodysplastic syndrome patients using standard methods. Aurora A mRNA and protein levels were correlated, as was aurora A mRNA level, with blast counts, cytogenetic abnormalities, and International Prognostic Scoring System score. We found that CD34(+) cells in myelodysplastic syndromes and acute myeloid leukemia expressed aurora A at significantly higher levels (P = 0.01 and P = 0.01, respectively) than normal CD34(+) cells. Aurora A mRNA levels correlated with total and phosphorylated protein levels (P = 0.0002 and P = 0.02, respectively). No significant correlation was found between aurora A mRNA level and blast count, blast viability, cytogenetic abnormalities, or the International Prognostic Scoring System score in patients with myelodysplastic syndromes. We conclude that aurora A is up-regulated in CD34(+) blasts from myeloid neoplasms.

Interaction of Akt-phosphorylated ataxin-1 with 14-3-3 mediates neurodegeneration in spinocerebellar ataxia type 1.

Spinocerebellar ataxia type 1 (SCA1) is one of several neurological disorders caused by a CAG repeat expansion. In SCA1, this expansion produces an abnormally long polyglutamine tract in the protein ataxin-1. Mutant polyglutamine proteins accumulate in neurons, inducing neurodegeneration, but the mechanism underlying this accumulation has been unclear. We have discovered that the 14-3-3 protein, a multifunctional regulatory molecule, mediates the neurotoxicity of ataxin-1 by binding to and stabilizing ataxin-1, thereby slowing its normal degradation. The association of ataxin-1 with 14-3-3 is regulated by Akt phosphorylation, and in a Drosophila model of SCA1, both 14-3-3 and Akt modulate neurodegeneration. Our finding that phosphatidylinositol 3-kinase/Akt signaling and 14-3-3 cooperate to modulate the neurotoxicity of ataxin-1 provides insight into SCA1 pathogenesis and identifies potential targets for therapeutic intervention.