CD10 AND CD34 EXPRESSION IN CHILDHOOD ACUTE LYMPHOBLASTIC LEUKEMIA IN MOROCCO: Clinical Relevance and Outcome

CD10 and CD34 expression in 86 Moroccan children with acute lymphoblastic leukemias (ALL) and the relevance to prognosis, diagnosis, and outcome during a 5-year follow-up were examined. At diagnosis, 57% of patients had CD10⁺ blasts, while 35% had CD34⁺ blasts. The CD10⁺ blast frequency was much higher (80%) in B-ALL than in T-ALL (20%). The frequency of CD34⁺ blasts was higher in B-ALL (48%) compared to T-ALL (16%). The 5-year survival curves showed that children with CD10⁺ B-ALL had a significantly longer survival rate than those with CD10^?, as observed for T-ALL. The survival rate of B-ALL expressing CD34 was higher than that of CD34^?. Thus, CD34 and CD10 expression may have prognostic value and is associated with a better clinical outcome.     

Acute lymphoblastic leukemia in children: Immunologic,cytochemical, morphologic,and cytogenetic studies in relation to pretreatment risk factors

Thirty children with previously untreated acute lymphoblastic leukemia were studied prior to therapy to determine whether sheep erythrocyte (E)-receptor status correlated with clinical factors, cytochemical staining characteristics, FAB morphologic classification, and karyotype. Five patients (17%) with more than 50% E⁺ blasts had intense focal acid phosphatase staining and distinct clinical characteristics, including high leukocyte counts, mediastinal masses, and involvement of the central nervous system at diagnosis. Focal acid phosphatase activity was present in blasts of patients with greater than 20% E⁺ blasts, but this group had fewer poor risk factors. Morphologic and karyotypic features were not related to erythrocyte-receptor status, but the L2 morphologic appearance occurrred more frequently in older patients (P < 0.05). Erythrocyte receptors have both qualitative and quantitative clinical correlations in childhood acute lymphoblastic leukemia; however, E⁺ and E^- groups are heterogeneous and E⁺ groups must be analzyed for other risk factors and relapse rates determined before firm conclusions can be made about erythrocyte rosetting as an independent risk variable.     

Value of flow cytometric analysis of peripheral blood samples in children diagnosed with acute lymphoblastic leukemia

Diagnostic procedures in children with acute lymphoblastic leukemia (ALL) are typically performed under general anesthesia. Anticipation of the diagnosis based on findings in peripheral blood allows scheduling of the first dose of intrathecal chemotherapy and diagnostic bone marrow (BM) aspirate during a single anesthetic. We retrospectively compared paired results of peripheral blood (PB) flow cytometric analysis and BM evaluation in 383 children with ALL diagnosed consecutively at a single center and found very high concordance of results between both tests. We conclude that PB flow cytometry may help streamline planning of procedure‐related anesthetics during diagnosis and early treatment of childhood ALL.     

The effect of short-course high-dose methylprednisolone on peripheral blood CD34+ progenitor cells of children with acute leukemia during remission induction therapy

This study was undertaken to determine the effect of short-course high-dose methylprednisolone (HDMP) treatment on peripheral blood (PB) CD34+ progenitor cells during remission induction treatment in 11 children with newly diagnosed acute leukemia (7 with ALL, 4 with AML) whose bone marrow (BM) cells expressed fewer than 5% CD34 at the time of diagnosis. All children who had no infection were given HDMP as a single daily oral dose of 30 mg/kg for the first four days of induction therapy. The number of CD34+ progenitor cells were determined by flow cytometry before and after four days of HDMP treatment. While the number of PB blast cells significantly decreased after only a four-day course of HDMP treatment, the number of PB CD34+ progenitor cells increased in all patients. In addition, after four days of HDMP treatment polymorphonuclear leukocytes (PMN) and mononuclear cells (MNC) increased significantly (p < 0.05). We suggest that the potential beneficial effects of HDMP in the induction treatment of acute leukemia may occur partly by the stimulation of PB CD34+ hematopoietic progenitor cells in a short period of time.     

Therapy Response Correlates with ALDH Activity in ALDH Low-Positive Childhood Acute Lymphoblastic Leukemias

The malignant cells of childhood acute lymphoblastic leukemia (ALL) do not form a homogenous entity but a collection of differently maturated blasts. The most immature leukemia cells may be more resistant to therapy than the bulk of more differentiated blasts. We studied 42 patients with childhood ALL treated according to the ALL-BFM 2000 protocol. At diagnosis, we determined the immunophenotype and the aldehyde dehydrogenase (ALDH) activity of the leukemic cells. Additionally, we investigated the expression of CD34, CD38 and CD45 to define a population of immunophenotypically immature cells (CD34⁺/CD38^?/CD45^?/low). We then studied levels of minimal residual disease (MRD) after induction therapy (day 33) to determine therapy response. Including all cases (n = 42), there was no correlation between ALDH positive cells, CD34⁺/CD38^?/CD45^?/low cells and MRD levels. A subset of 18 ALLs displayed a more mature phenotype with low-ALDH positivity (< 1%). Analyzing this cohort, ALDH positive blasts overlapped with the CD34⁺/CD38^?/CD45^?/low population. The initial rate of ALDH positivity correlated with MRD levels at day 33 of therapy (r = 0.61, P < .01). We conclude that in pediatric ALL, ALDH positivity as a marker of immaturity and stemness has prognostic significance only in phenotypically mature cases when the ALDH activity is not a property of the majority of the leukemic blasts. In case of an immature ALL phenotype, ALDH activity might be an inherent characteristic of the whole leukemia and is not limited to a more immature subpopulation that could confer to resistance and increased MRD-levels during therapy.     

Prognostic impact of CD200 and CD56 expression in pediatric B-cell acute lymphoblastic leukemia patients

This study aimed to determine the prognostic impact of CD200 and CD56 expression in pediatric B cell acute lymphoblastic leukemia (B-ALL) patients, both of which have been implicated in immune tolerance and previously suggested as independent risk factors. CD200 has a central role in immune tolerance that protects stem cells and other critical tissues from immune damage. The expression of CD200/CD56 in leukemic blasts were assessed in leukemic blasts before chemotherapy in 43 bone marrow (BM) and/or peripheral blood (PB) samples by flow cytometry. Twenty eight of 43 B-ALL cases (65%) showed CD200 positive expression, 5 of 43 cases (11.6%) showed CD56 expression, and only 2 patients (4.7%) expressed both CD200 and CD56. Patients with CD200⁺ and CD56⁺ were significantly associated with lower platelet count; less tendency for induction of remission response as compared to negative ones (p = .01 for both). The overall survival (OS) and DFS were significantly shorter in CD200⁺ and CD56⁺ cases as compared to those with CD200^? and CD56^? expression. In conclusion, CD200 and/or CD56 positive expression in B-ALL at diagnosis suggest a poor prognosis and may be associated with biological aggressiveness.     

Initial response to therapy as an important prognostic factor in acute lymphoblastic leukemia in childhood. COALL study group

Prognostic factors to estimate the risk of relapse are crucial for risk-adapted therapy in acute lymphoblastic leukemia (ALL). In a cooperative multicenter treatment study for childhood ALL (COALL-03-85) the prognostic relevance of the bone marrow (BM) blast count at day 28 was evaluated. Treatment was adjusted to the initial risk factors; patients with high risk (white blood count (WBC) greater than or equal to 25/nl, age greater than or equal to 10 years, T- or NULL-ALL) received intensified therapy consisting of rotation of 6 non cross-resistant drug combinations with 12 different agents. After 4 weeks 289/305 (94.8%) children were in complete remission (CR); one child died of infection, and 15 (14 high-risk patients) still had more than 5% blasts in the BM. Twelve of these 15 patients were in remission after 2 to 4 weeks additional treatment. Poor responders often had a high initial WBC, age above 10 years of T- or NULL-ALL. In spite of continuation of intensive therapy all children with more than 10% blasts in the BM on day 28 suffered an early relapse except 2 who were transplanted in first remission. Event-free survival for the poor responders is 0.15 compared to 0.71 (p = 0.0001) for the good responders (median observation time 48 months). In multivariate analysis remission status on day 28 was the only significant prognostic factor in high-risk patients above one year of age; traditional risk factors as initial WBC, age above 10 years, hepatosplenomegaly, and immunological subtype were of no prognostic significance in this study. (ABSTRACT TRUNCATED AT 250 WORDS)     

Phagocytic activity and expression of myeloid-associated cell surface antigens by blast cells in acute lymphoblastic leukemia

The malignant cells of patients with acute lymphoblastic leukemia (ALL) rarely show phagocytic activity. In this retrospective survey, blasts from 7 of 196 patients with newly diagnosed ALL demonstrated phagocytic activity toward platelets and erythrocytes. The morphology and cytochemical staining properties of the cells were typical of ALL. Immunophenotyes were those of common ALL (CALLA+, HLA-DR+) for six patients and of pre-B-cell ALL (positive cytoplasmic immunoglobulin) for one. However, blast cells from six of the seven patients also reacted with myeloid-associated monoclonal antibodies (MCS.2 and/or SJ-D1). The wide overlap in the percentages of blasts expressing CALLA and those expressing myeloid-associated antigens suggests that some cells possessed both lymphoid- and myeloid-associated surface antigens. By a dual staining technique, two patients tested had blasts expressing antigens of both lineages. Each child achieved a complete remission after treatment with agents effective for ALL and remains in remission for 13+ to 20+ months. These morphologic and immunologic findings may define a distinct subtype of acute leukemia.     

Cytokinetic studies in children with untreated acute lymphocytic leukaemia (ALL): relationship to "T" cell markers.

"The labelling index (LI), mitotic index (MI) of marrow lymphoblasts and the percent of peripheral blood lymphocytes and lymphoblasts that form rosettes with sheep red cells at 4 degrees C ("T4"), were measured at presentation in 33 children with ALL. There was a significant correlation between LI and MI, but no significant correlations between them and the total white cell count at diagnosis or the "T4" percent. Three patients had greater than 55% "T4" rosettes and showed increased LI and MI, and 2 have relapsed; 12 had less than 20% "T4" rosettes, showed an increased LI (LI greater than 8% in 8 of 12) but not MI, and 5 have relapsed; 18 had 20--55% "T4" rosettes and generally had the lowest LI (LI less than 8% in 11 of 18), and only 3 have relapsed. Our findings suggest that patients with high and low percentage of "T4" rosettes in the peripheral blood have an increased fraction of leukaemic cells in DNA synthesis and have a diminished chance of prolonged remission.     

Daunorubicin-induced cell kill with 1-hour versus 24-hour infusions: a randomized comparison in children with newly diagnosed acute lymphoblastic leukemia

BACKGROUND: Daunorubicin (DNR) is one of the most important drugs in treatment of acute lymphoblastic leukemia (ALL). Prolonged infusions of anthracyclines are less cardiotoxic but it has not been investigated whether the in vivo leukemic cell kill is equivalent to short-term infusions. PROCEDURE: In the cooperative treatment study COALL-92 for childhood ALL 178 patients were randomized to receive in a therapeutic window a single dose of 36 mg/m (2) DNR either as a 1-h (85 patients) or 24-h infusion (93 patients). Daily measurements of white blood cell count (WBC) and peripheral blood smears for seven days could be evaluated centrally in 101 patients (1-h: 43 patients, 24-h: 58 patients). RESULTS: The proportional decline of blasts at day 7 after DNR infusion showed no statistically significant difference between the two treatment arms. At day 3 the median percentage of blasts was less than 10%, at day 7 less than 2% for either the 1-h or 24-h infusion. Twelve patients (1-h: 5 patients, 24-h: 7 patients) had an absolute number of more than 1000 blasts per mul peripheral blood (PB) at day 7 after DNR infusion (DNR poor responders). Kaplan-Meier analysis showed an equal probability of EFS for the short- and long-term infusion group (24-h: 83%+/-5; 1-h: 81+/-6) after a median observation time of 12.3 years. CONCLUSIONS: We conclude that in children with ALL a 24-h infusion of DNR has the same in vivo cytotoxicity for leukemic cells as a 1-h infusion. This offers the possibility to use prolonged infusions with hopefully less cardiotoxicity without loss of efficacy.     

Differential mRNA expression of glucocorticoid receptor alpha and beta is associated with glucocorticoid sensitivity of acute lymphoblastic leukemia in children

BACKGROUND: Sensitivity of leukemic blasts to glucocorticoid is one of the important prognostic factors for pediatric acute lymphoblastic leukemia (ALL). Alternative splicing of the glucocorticoid receptor (GR) gene results in several isoforms. We examined an association of the expression pattern of GR isoforms in leukemic blasts with their sensitivity to glucocorticoid in childhood ALL. PROCEDURES: The relative mRNA expression of GRalpha, GRbeta, GRgamma, and GR-P was determined in leukemic blasts of 23 childhood ALL at initial presentation and of 14 ALL cell lines by quantitative RT-PCR. Glucocorticoid-sensitivity of leukemic blasts was determined by counting apoptotic cells with flow cytometry after 6-hr incubation with prednisolone (PSL). RESULTS: The relative expression of GRalpha mRNA was significantly higher in blasts of B-precursor ALL than those of others (13.6 vs. 2.24, P = 0.015), while those of GRalpha, GRbeta, and GRgamma showed no difference. GRbeta/GRalpha ratios were significantly lower in B-precursor ALL than others (0.80 vs. 4.64, P = 0.035). The proportions of apoptotic cells after PSL exposure were inversely correlated with the GRbeta/GRalpha ratios in ALL cell lines (r = -0.612, P = 0.020). PSL administration induced apoptosis efficiently in leukemic blasts with low GRbeta/GRalpha ratios compared with those of high ratios (cell lines: 4.93% vs. 1.90%, P = 0.013, primary leukemia: 11.7% vs. 3.6%, P = 0.037). CONCLUSIONS: The amounts of GR isoform mRNA in leukemic blasts were closely correlated with sensitivity to glucocorticoid exposure. The mRNA expression pattern of GR isoforms at initial presentation may provide valuable information for prognosis in children with newly diagnosed ALL.     

Chemokine IL-8 and chemokine receptor CXCR3 and CXCR4 gene expression in childhood acute lymphoblastic leukemia at first relapse

In this study, we examined the gene expression of interleukin (IL)-8, CXCR3, and CXCR4 in leukemic cells from 100 children with relapsed B-cell progenitors (BCP) acute lymphoblastic leukemia (ALL), using quantitative real-time polymerase chain reaction (RT-PCR). IL-8, CXCR3, and CXCR4 were expressed in almost all bone marrow (BM) samples. The CXCR4 expression significantly correlated with known prognostic factors at relapse: time point and site of relapse. Patients who had a combined BM relapse (n=21) had lower IL-8 and CXCR4 expression than those who had an isolated BM relapse (n=79). The CXCR3 expression was higher in female patients (n=39) than in male patients (n=61). However, this did not reach prognostic relevance in relapsed ALL.     

Glucocorticoid receptors in acute lymphoblastic leukemia in children]

Glucocorticoid receptor (GR) levels were quantitated in leukemic blasts from bone marrow aspirates of 53 children with acute lymphoblastic leukemia (ALL) and compared to the clinical and immunological features of the disease and its prognosis. GR levels did not correlate with the patients' sex, peripheral white blood cell count and cellular immunophenotype, but depended on the patients' age and histological type of leukemia. 43 patients were monitored during 3 or more years. The relapse-free and overall survival of ALL patients receiving standard courses of polychemotherapy including glucocorticoids was highly dependent on the GR level in bone marrow blasts. The best prognosis (67% relapse-free and 73% overall 3-years' survival) was observed in patients with GR levels over 6,000 sites/cell and patients with GR levels under 3,000 sites/cell had poor prognosis (31% relapse-free and 50% overall survival; median 1st remission duration 12 months). These correlations were most pronounced in ALL patients with "common" antigen.     

Cytokinetic studies in children with untreated acute lymphocytic leukaemia (ALL): Relationship to “T” cell markers

The labelling index (LI), mitotic index (MI) of marrow lymphoblasts and the percent of peripheral blood lymphocytes and lymphoblasts that form rosettes with sheep red cells at 4°C (“T₄”), were measured at presentation in 33 children with ALL. There was a significant correlation between LI and MI, but no significant correlations between them and the total white cell count at diagnosis or the “T₄” percent. Three patients had > 55% “T₄” rosettes and showed increased LI and MI, and 2 have relapsed; 12 had < 20% “T₄” rosettes, showed an increased LI (LI > 8% in 8 of 12) but not MI, and 5 have relapsed; 18 had 20–55% “T₄” rosettes and generally had the lowest LI (LI < 8% in 11 of 18), and only 3 have relapsed. Our findings suggest that patients with high and low percentage of “T₄” rosettes in the peripheral blood have an increased fraction of leukaemic cells in DNA synthesis and have a diminished chance of prolonged remission.     

Marked increase of peripheral blood myeloblasts following G-CSF therapy in a patient with acute lymphoblastic leukemia

A 9 year old boy with acute lymphoblastic leukemia (ALL) received recombinant human granulocyte colony-stimulating factor (rhG-CSF) and showed a marked increment of myeloblasts in the peripheral blood. He was administered repeated courses of intermediate-dose cytosine arabinoside (Ara-C) therapy (1500 mg/m², days 1–5) for frequent central nervous system (CNS) relapse of ALL. The peripheral white blood cell nadir was less than 1000/μL, so he was treated with rhG-CSF. A marked increment of peripheral blood blasts was noted 3–5 days after rhG-CSF treatment. These cells decreased with the appearance of mature myeloid cells and disappeared about 2 weeks after the start of treatment. These findings suggested that the blasts might have the ability to differentiate into mature myeloid cells. A control patient with repeated CNS relapse of ALL showed no increment of peripheral blood blasts after similar repeated courses of Ara-C without rhG-CSF treatment. Cultured peripheral blood blasts obtained from the present patient showed differentiation into mature myeloid cells by morphological studies and surface marker analysis. These findings indicate that the peripheral blood blasts drawn by G-CSF were not leukemic blasts but normal myeloblasts.     

Acute Leukemia with Normal Platelet Count at Diagnosis

Thirty-six (17.8%) of 202 children with acute lymphoblastic leukemia (ALL) and 2 (3.7%) of 54 children with acute nonlymphoblastic leukemia (ANLL) had a platelet count over 150 times 10⁹/1 at diagnosis. Children with ALL and a platelet count over 150 times 10⁹/1 were analysed in detail. The ALL patients without thrombocytopenia tended to be male predominant and had less frequent bleeding manifestations (p < 0.01).These patients without thrombocytopenia had also significantly less marked leukocytosis (p < 0.01), less severe anemia (p < 0.05) and lower percentages of bone marrow blasts (p < 0.05) than those with thrombocytopenia. In addition, ALL patients without thrombocytopenia had a significantly higher probability of continuous complete remission than those with thrombocytopenia (p < 0.01).     

Treatment of high-risk acute lymphoblastic leukemia in children using the AL851 and ALHR88 protocols: A report from the Kyushu-Yamaguchi children cancer study group in Japan

A total of 125 children, who were diagnosed as having high-risk acute lymphoblastic leukemia (ALL), were treated with two consecutive protocols designated as AL851 (1985–1988) and ALHR88 (1988–1990). All patients received induction therapy consisting of vincristine (VCR), prednisolone (PSL), daunorubicin (DNR), and l-asparaginase (l-Asp). In the ALHR88 protocol, the patients whose blasts in the bone marrow (BM) were ≥25% on day 14 of induction therapy and who were classified into T-cell type received additional cytosine arabinoside (AraC). After consolidation with intermediate-dose methotrexate (MTX), reinduction therapy including VCR, dexamethasone, and adriamycin followed by high-dose AraC was done for all patients. Intrathecal MTX and 24Gy of cranial irradiation were used to prevent central nervous system leukemia. A maintenance therapy consisting of 6-mercaptopurine, cyclophosphamide, MTX, DNR, VCR, and AraC was administered for 3 years after achieving a complete remission (CR). CR was achieved in 51/55 (92.7%) for AL851 and 68/70 (97.1%) for ALHR88. The 5-year event-free survival rates were 49.1 ± 6.7% in AL851 and 62.5 ± 6.1% in ALHR88. The factors related to a poor prognosis were a high initial leukocyte count of greater than 50 × 10⁹/L (P < 0.001), an L2 morphology of leukemic cells by FAB classification (P = 0.009), the chromosomal abnormality (P = 0.004) and high residual leukemic cells in BM (≥25%) on day 14 of induction therapy (P < 0.001). Taking these factors into consideration, more intensive protocols were started in 1990 for the patients with high-risk ALL. © 1996 Wiley-Liss, Inc.     

Colony Forming Capacity in Children with Normal Bone Marrow and Leukemia

The in vitro colony formation in 27 children with normal bone marrow and 37 children with acute leukemia (25 cases at onset or relapse and 12 cases during complete remission) has been studied. The number of colonies per 2 × 10⁵ cells in children with normal bone marrow ranged from 110 to 504 and the average count was 248 colonies. This was a higher number of colonies than that reported in adult bone marrow. The colonies were about 65% compact colonies and about 35% loose colonies. In 19 cases of acute leukemia with the blasts in excess of 95% at onset or relapse, there was generally a decrease in colony forming capacity. One case of ALL showed an almost normal colony forming capacity. All of the 6 cases with the blasts of 30 to 60% developed colonies, but the number of colonies was less than that of normal bone marrow. Colony forming capacity in 12 cases with remission was similar to normal bone marrow. From the results, it is considered that in general colony formation in acute leukemia may be related to the ratio of blasts found in the bone marrow; however, in some cases of acute leukemia at onset or relapse there may be blasts that can differentiate and maturate.     

Quantification of Nucleated Cells,CD34-Positive Cells and CFU-GM Colonies in Single Bone Marrow Samples and Bone Marrow Harvests Derived from Healthy Children

Little is known regarding bone marrow (BM) cellularity, CD34+ fraction, and CFU-GM colony formation in relation to age and whether healthy children require a reference range distinct from healthy adults. We therefore analyzed a series of single BM aspirates from 45 healthy children who were evaluated as potential BM donors. Thirty-three of these children subsequently donated BM. We quantified the nucleated cell count, fraction of CD34+ cells, and number of CFU-GM colonies in single aspirates and BM harvests. Single aspirates displayed a mean nucleated cell count of 31.3 × 10⁶ cells/mL, a mean fraction of 1.17% CD34+ cells, and a mean colony forming potential of 66.6 CFU-GM/10⁵ cells. Harvests yielded the same number of nucleated cells but increased numbers of CD34+ cells and CFU-GM compared with single aspirates. The mean nucleated cell count in BM harvests was 31.1 × 10⁶ /mL with a mean fraction of 1.95% CD34+ cells and a mean of 112.4 CFU-GM colonies/10⁵ cells. The concentration of nucleated cells was elevated compared with reported adult counts, while CD34+ percentage and CFU-GM counts were similar. In this series of healthy children, the fraction of CD34+ cells, CFU-GM colonies, and nucleated cells decreased with age. We did not identify gender specific differences. To our knowledge, this represents the first comprehensive study of CD34+ cell fraction, CFU-GM counts, and nucleated cell numbers in the BM of healthy children. The findings provide valuable information for practical use for BM transplantation and contribute to the understanding of hematopoiesis from birth to adulthood.