Sema Anak

The MN1 (Meningioma 1) gene is overexpressed in certain subtypes of acute myeloid leukemia (AML) and high levels of MN1 expression in mouse bone marrow cells results in myeloid leukemia. We showed that compared with control bone marrow (BM) MN1 expression was increased (2-fold or more) in 29 out of 73 (40%) pediatric B-cell acute lymphoblastic leukemia (B-ALL) patient BM. Additional analysis of MN1 expression in sub-groups within our cohort carrying different chromosome translocations showed that carriers of the good prognostic marker t(12;21)(TEL-AML1) (n=27) expressed significantly more MN1 than both healthy controls (n=9) (P=0.02) and the group carrying the t(9;22)(BCR-ABL) (n=9) (P=0.001). In addition, AML1 expression was also upregulated in 31 out of 45 (68%) B-ALL patient BM compared with control and there was a significant correlation between MN1 and AML1 expression (r=0.3552, P=0.0167). Retroviral MN1 overexpression increased the colony forming activity of mouse Pro-B/Pre-B cells in vitro. Our results suggest that deregulated MN1 expression contributes to the pathogenesis of pediatric B-ALL. Further investigation into the clinical and biological significance of elevated MN1 expression in TEL-AML1(positive) leukemia might provide insight into additional molecular mechanisms contributing to B-ALL and may lead to improved treatment options for patients.

Gardner Diamond syndrome is a rare condition characterized with painful ecchymoses in different parts of the body and cutaneous and mucosal hemorrhages. The etiology is not known fully and psychogenic factors are thought to be involved. Cutaneous lesions and hemorrhages develop mostly following emotional stress and rarely minor traumas and may recur. Although the extremities are involved with the highest rate, the lesions may be observed in any part of the body. Hemostatic tests are generally normal. The majority of the subjects is composed of young women. It is observed more rarely in men and children. In this article, a patient who presented with recurring painful echymoses and bleeding disorder and diagnosed with Gardner Diamond syndrome by intracutaneous injection of autologous blood was presented to emphasize that this syndrome is observed rarely in the childhood and should be considered not only in the differential diagnosis of cutaneous lesions, but also in the differential diagnosis of various system hemorrhages.

T-cell acute lymphoblastic leukemia (T-ALL) is associated with recurrent chromosomal aberrations andabnormal ectopic gene expression during T-cell development. In order to gain insight into the pathogenesis of T-ALLthis study aimed to measure the level of expression of 7 T-cell oncogenes (LMO2, LYL1, TAL1, TLX1, TLX3, BMI1, andCALM-AF10) in pediatric T-ALL patients Material and Methods: LMO2, LYL1, TLX1, TLX3, BMI1, TAL1, and CALM-AF10 expression was measured usingquantitative real-time PCR in 43 pediatric T-ALL patients. A high level of expression of LMO2, LYL1, TAL1, and BMI1 genes was observed in a large group of T-ALL.Several gene expression signatures indicative of leukemic arrest at specific stages of normal thymocyte development(LYL1 and LMO2) were highly expressed during the cortical and mature stages of T-cell development. Furthermore,upregulated TAL1 and BMI1 expression was observed in all phenotypic subgroups. In all, 6 of the patients had TLX1and TLX3 proto-oncogene expression, which does not occur in normal cells, and none of the patients had CALM-AF10fusion gene transcription. Expression of LYL1 alone and LMO2-LYL1 co-expression were associated with mediastinalinvolvement; however, high-level oncogene expression was not predictive of outcome in the present pediatric T-ALLpatient group, but there was a trend towards a poor prognostic impact of TAL1 and/or LMO2 and/or LYL1 protooncogeneexpression. Poor prognostic impact of TAL1 and/or LMO2 and/or LYL1 proto-oncogene expression indicate the needfor extensive study on oncogenic rearrangement and immunophenotypic markers in T-ALL, and their relationship totreatment outcome. None declared.

To identify the well-known common translocations and FLT3 mutations in childhood acute myelogenousleukemia (AML) patients in Turkey. The study included 50 newly diagnosed patients in which t(15;17), t(8;21), and inv(16)chromosomal translocations were identified using real-time PCR and FLT3 gene mutations were identified via direct PCR amplification PCR-RE analysis. In all, t(15;17) chromosomal aberrations were observed in 4 patients (8.0%), t(8;21) chromosomal aberrationswere observed in 12 patients (24.0%), inv(16) chromosomal aberrations were observed in 3 patients (6.0%), and FLT3-ITD mutations were observed in 2 patients (4.0%); FLT3-D835 point mutation heterozygosity was observed in only 1patient (2.0%) patient. Despite of the known literature, a patient with FLT3-ITD and FLT3-D835 double mutation shows a bettersurvival and this might be due to the complementation effect of the t(15;17) translocation. The reportedmutation ratein this article (4%) of FLT3 gene seems to be one of the first results for Turkish population.

Li-Fraumeni syndrome (LFS) is one of the familial cancers characterized by different tumors and hereditary TP53 mutations. The adrenocortical carcinoma (ACC) association with acute leukemia is unusual in childhood, even in LFS. The authors here present a family with pR337P mutation in TP53 gene who had a child with acute lymphoblastic leukemia (ALL) and associated adrenocortical carcinoma as a case 1 and his cousin with brain tumor as a case 2. A hereditary TP53 mutation supported the diagnosis of LFS in this family. The patients had many difficulties in treatment strategies and succumbed to death. The availability of a reliable molecular marker to detect the R337P TP53 mutation allows the rapid identification of carriers in families that have a child with ACC. Once identified, carriers could be screened for early detection of ACC by imaging and endocrine studies and should be given psychological support to prevent anxiety for death. Whether early detection of ACC will reduce the mortality in these patients remains to be determined.

Treatment of childhood acute myelocytic leukemia (AML) in first remission, is still evolving. Allogeneic bone marrow transplantation (BMT) in patients with a donor has been well established, but the role of autologous transplantation remains of interest, particularly in the light of some encouraging results in adults. Out of 81 pediatric patients with AML in first CR, 67 were biologically randomized for allogeneic (n = 31), autologous (n = 20), or peripheral stem cell transplant (n = 16) after completing consolidation treatment, with the remaining (n = 11) dropping out or receiving chemotherapy. Disease free survival (DFS) of these different groups were analyzed. Allogeneic transplantation is not superior to autologous and autologous peripheral blood stem cell transplantation (PBSCT) (DFS in 5 years is 61%, 50%, and 75%). The 5 years DFS in the autologous PBSCT group is significantly better than in the autologous BMT group (75% vs. 50%, P < 0.05). In pediatric AML patients without a donor, autologous BMT or autologous PBSCT appears to be an effective treatment option with low transplant related mortality especially in less privileged countries where the chemotherapy only results are still low.

NAD(P)H:quinone oxidoreductase1 (NQO1) is a two-electron reductase that detoxifies quinones derived from the oxidation of phenolic metabolites of benzene. Exposure to benzene metabolites increases the risk of hematotoxicity and leukemia. NQO1 enzyme activity protects the cells against metabolites of benzene. C to T base substitution at nucleotide 609 of NQO1 cDNA (C609T) results in loss of enzyme activity. Low NQO1 activity may play a role in etiology of acute leukemia. We analyzed NQO1 C609T gene polymorphism using the PCR-RFLP method in 273 patients with de novo acute leukemia (189 acute lymphoblastic leukemia (ALL), and 84 acute myeloid leukemia (AML) and 286 healthy volunteers to investigate the role of NQO1 polymorphism in the etiology of acute leukemia. The frequency of homozygosity for NOQ1 C609T polymorphism was 3.5% in the healthy control population and 2.5% in pediatric acute leukemia. The NQO1 C609T allele frequency was not statistically different in the children with acute leukemia in comparison to the controls (odds ratio (OR), 0.76; 95% confidence interval (CI), 0.58-1.01; P = 0.06). The distribution of NQO1 genotypes among children with acute leukemia was not statistically different from the control group (P = 0.13). These findings do not support the role of NQO1 C609T polymorphism in the etiology of de novo pediatric acute leukemia.

Despite the introduction of new broad-spectrum antibiotics and antifungal therapies over the past decade, infections remains the most frequent cause of death in patients with neutropenia. The aim of this study is to assess the effect and safety of granulocyte transfusions (GTX) for the treatment of severe life-threatening infections in pediatric patients with febrile neutropenia or defective granulocyte functions. In this study, 35 pediatric patients with high-risk febrile neutropenia or defective granulocyte functions, who received 111 GTX, were included. GTX were used for 3 consecutive days during infections not responding to antimicrobial therapy. The mean granulocyte content per concentrate was 27.4×10⁹ (min: 4.2×10⁹ to max: 68.4×10⁹) depending on donor's white blood cell count before harvest. GTX were well tolerated in all patients. The infection-related survival rate was 82.4% and overall survival rate was 77.1% at day 30. The overall survival rate was 65.7% and 52% at 3 and 48 months, respectively. GTX is safe and effective in controlling the life-threatening infections. Further randomized controlled studies with long-term follow-up are needed to assess the exact role of GTX in the outcome of patients with neutropenia and patients with defective granulocyte functions.

An 8.5-year-old girl who presented with chronic cough and hemoptysis underwent a CT scan of the chest showing diffuse mediastinal and parenchymal infiltration and pleural effusion, and laboratory findings showed disseminated intravascular coagulation. Disseminated lymphangiomatosis was diagnosed after an open-lung biopsy. She was treated by systemic steroids, interferon, tamoxifen, chemotherapy, and radiation but died of respiratory failure and disseminated intravascular coagulation 2 years after the diagnosis. This patient represents a rare presentation of diffuse pulmonary lymphangiomatosis together with disseminated intravascular coagulation, involving both the mediastinum and pulmonary parenchyma, in a child.

Haematopoietic stem cell transplantation (HSCT) remains the best therapeutic option for many acquired and inherited paediatric haematological disorders. Unfortunately, the probability of finding an HLA matched donor is limited. An alternative technique is PGD combined with HLA matching, which offers the possibility of selecting unaffected embryos that are HLA compatible with the sick child, with the aim of possible use of stem cells from the resulting baby in future. Since the first successful report for Fanconi anaemia a decade ago, the therapeutic success of this technique was reported in a few cases and for a limited number of disorders. Here, we report full recovery of 44 sick children who received HSCT from healthy infants conceived after pre-implantation HLA matching for the following 10 indications; beta-thalassaemia, Wiskott-Aldrich syndrome, Fanconi anaemia, sickle cell anaemia, acute myeloid leukaemia, acute lymphoblastic leukaemia, Glanzmann's thrombasthaenia, Diamond-Blackfan anaemia, X-linked adrenoleukodystrophy and mucopolysaccharidosis type I. No serious complications were observed among recipients and donors. Graft failure occurred in four children with beta-thalassaemia where a second HSCT was planned. Preimplantation HLA matching is a reliable technique and provides a realistic option for couples seeking treatment for an affected child when no HLA-matched donor is available.