Pentoxifylline during steroid window phase at induction to remission increases apoptosis in childhood with acute lymphoblastic leukemia

Purpose

Pentoxifylline (PTX) has been shown to increase chemotherapy-induced apoptosis. A clinical trial was developed to evaluate the effect of the addition of PTX to the induction steroid window phase in children with acute lymphoblastic leukemia (ALL).

Methods

Thirty-two children were enrolled on this study. Children with a new diagnosis of ALL were randomly assigned to receive prednisone (PRD) 40 mg/m²/day only during the 7-day treatment pre-phase (PRD group, 11 patients) or to receive PRD with PTX (10 mg/kg/day) (PTX group, 11 patients); the control group included children with normal bone marrow (10 patients). Bone marrow aspiration (BMA) was performed at diagnosis (day ?7) in all groups, and at day 0 (end of PRD window) for patients with ALL (PRD and PTX groups). Apoptosis was evaluated by flow cytometry (FC) using Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) stains. Statistical analysis was performed using the Mann–Whitney U test.

Results

Apoptotic index at day ?7 was similar in all groups. However, at day 0 post-treatment, apoptosis was significantly higher in the PTX group than in the PRD group (p < 0.001). There were no serious adverse effects associated with PTX.

Conclusions

PTX potentiates blast apoptosis induced by PRD in children with ALL during steroid window phase.

     

Use of medication during pregnancy and risk of childhood leukemia (Canada)

ObjectiveTo examine risk of childhood acute lymphoblastic leukemia (ALL) associated with maternal use of medications during pregnancy; in particular medications known or suspected to be teratogenic. Methods: Seven hundred and eighty nine children (<15years old) diagnosed with ALL in the province of Québec between 1980 and 2000 were recruited for study. A similar number of population based controls matched to cases (1:1) by sex and age were chosen from family allowance or health insurance files. Information was gathered via telephone interview with the subjects parents. Data were analyzed using conditional logistic regression. Results: Risk of childhood ALL was significantly increased in the offspring of mothers who reported using any medication (adjusted odds ratio (OR_adj)=1.3, 95 CI=1.0–1.6) or any teratogenic medication (OR_adj=1.4, 95 CI=1.1–1.9) during pregnancy. Among specific medication categories, only central nervous system depressants were associated with a significantly increased risk, although elevated odd ratios were found for anti-epileptics, immunosuppressants, oral contraceptives, and illicit drugs. Risk associated with use of teratogenic medications was higher with increased dose and in children diagnosed before two years of age. Conclusion: A modest increase in risk of ALL was found among children of mothers who used medication during pregnancy.     

DNA repair gene XRCC1 polymorphisms and susceptibility to childhood acute lymphoblastic leukemia: a meta-analysis

Objective

To estimate the relationship between genetic polymorphisms of X-ray repair cross-complementing group 1 (XRCC1) and the susceptibility to childhood acute lymphoblastic leukemia (ALL).

Methods

Relevant case-control studies were enrolled in the meta-analysis. We applied Rev Man 4.2 software to pool raw data and test studies’ heterogeneity and to calculate the incorporated odds ratio (OR) and 95% confidence interval (95% CI).

Results

Our data showed that the OR for the Gln allele of the Arg399Gln polymorphism, compared with the Arg allele, was 1.35 (95% CI, 1.16-1.57; P<0.0001) for childhood ALL patients. Similarly, the homozygous genotype Gln/Gln and heterozygous genotype Arg/Gln both significantly increased the risk of childhood ALL compared with the wild genotype Arg/Arg (OR =1.58; 95% CI, 1.13-2.21; P=0.008; OR =1.51; 95% CI, 1.21-1.87; P=0.0002). The dominant model of Arg399Gln was associated with childhood ALL risk (OR =1.54; 95% CI, 1.25-1.89; P<0.0001). The ethnic subgroup analysis demonstrated that the Gln allele in all five ethnic groups was prone to be a risk factor for childhood ALL just with different degrees of correlation while Arg194Trp SNP showed a protective or risk factor or irrelevant thing in different races.

Conclusions

XRCC1 399 polymorphism may increase the risk of childhood ALL. Different ethnic groups with some gene polymorphism have different disease risks.Key Words: X-ray repair cross-complementing group 1 (XRCC1), gene polymorphism, childhood, acute lymphoblastic leukemia (ALL)     

Risk of childhood acute lymphoblastic leukaemia following parental occupational exposure to extremely low frequency electromagnetic fields

Background:

Earlier studies have reported moderate increases in the risk of acute lymphoblastic leukaemia (ALL) among children whose mothers have been occupationally exposed to extremely low frequency (ELF) electromagnetic fields. Other studies examining parental occupational exposure to ELF and ALL have reported mixed results.

Methods:

In an Australian case–control study of ALL in children aged <15 years, parents were asked about tasks they undertook in each job. Exposure variables were created for any occupational exposure before the birth of the child, in jobs 2 years before birth, in jobs 1 year before birth and up to 1 year after birth.

Results:

In all, 379 case and 854 control mothers and 328 case and 748 control fathers completed an occupational history. Exposure to ELF in all time periods was similar in case and control mothers. There was no difference in exposure between case and control fathers. There was no association between maternal (odds ratio (OR)=0.96; 95% CI=0.74–1.25) or paternal (OR=0.78; 95% CI=0.56–1.09) exposure to ELF any time before the birth and risk of childhood ALL.

Conclusion:

We did not find an increased risk of ALL in offspring of parents with occupational exposure to ELF.     

A report about treatment refusal and abandonment in children with acute lymphoblastic leukemia in China, 1997-2007

Background

To analyze the causes and consequence of treatment refusal and abandonment in childhood acute lymphoblastic leukemia (ALL) treated in Wuhan Union Hospital of China.

Methods

We collected recorded data and interviewed families of the children with ALL diagnosed between January 1997 and August 2007, who refused or abandoned treatment.

Results

323 patients were diagnosed with ALL. 173 patients (173/323, 53.6%) refused therapy and 35 (35/323, 10.8%) cases abandoned treatment. 191 (191/208, 91.8%) of these children were telephone/mail-visited. Different people had different reasons for refusal or abandonment. Financial difficulty and belief of ALL incurability were the main reasons for abandonment. Transportation difficulties and fear of severe side effects were also important reasons. Of the 173 patients who refused treatment, 13 patients lost follow-up. 160 parents were interviewed and 1 (6.3%) child was still alive at the date of last follow-up. Of the 35 patients who abandoned treatment, 4 patients lost follow-up. 31 parents were interviewed and 2 (6.5%) children were still alive at the date of last follow-up.

Conclusion

Medical insurance and a systemic health education are extremely required for childhood ALL in low middle income countries.     

Genetic susceptibility in childhood acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy and a leading cause of death due to disease in children. The genetic basis of ALL susceptibility has been supported by its association with certain congenital disorders and, more recently, by several genome-wide association studies (GWAS). These GWAS identified common variants in ARID5B, IKZF1, CEBPE, CDKN2A, PIP4K2A, LHPP and ELK3 influencing ALL risk. However, the risk variants of these SNPs were not validated in all populations, suggesting that some of the loci could be population specific. On the other hand, the currently identified risk SNPs in these genes only account for 19% of the additive heritable risk. This estimation indicates that additional susceptibility variants could be discovered. In this review, we will provide an overview of the most important findings carried out in genetic susceptibility of childhood ALL in all GWAS and subsequent studies and we will also point to future directions that could be explored in the near future.     

Trends in childhood leukemia incidence over two decades from 1992 to 2013

Incidence rates of childhood leukemia in the United States have steadily increased over the last several decades, but only recently have disparities in the increase in incidence been recognized. In the current analysis, Surveillance, Epidemiology and End Results (SEER) data were used to evaluate recent trends in the incidence of childhood leukemia diagnosed at age 0–19 years from 1992 to 2013, overall and by age, race/ethnicity, gender and histologic subtype. Hispanic White children were more likely than non‐Hispanic White, non‐Hispanic Black or non‐Hispanic Asian children to be diagnosed with acute lymphocytic leukemia (ALL) from 2009 to 2013. From 1992 to 2013, a significant increase in ALL incidence was observed for Hispanic White children [annual percent change (APC)_Hispanic = 1.08, 95% CI: 0.59, 1.58]; no significant increase was observed for non‐Hispanic White, Black or Asian children. ALL incidence increased by about 3% per year from 1992 to 2013 for Hispanic White children diagnosed from 15 to 19 years (APC = 2.67; 95% CI: 0.88, 4.49) and by 2% for those 10–14 years (APC = 2.09; 95% CI: 0.57, 3.63), while no significant increases in incidence were observed in non‐Hispanic White, Black, or Asian children of the same age. Acute myeloid leukemia (AML) incidence increased among non‐Hispanic White children under 1 year at diagnosis, and among Hispanic White children diagnosed at age 1–4. The increase in incidence rates of childhood ALL appears to be driven by rising rates in older Hispanic children (10–14, and 15–19 years). Future studies are needed to evaluate reasons for the increase in ALL among older Hispanic children.     

Maternal fetal loss history and increased acute leukemia subtype risk in subsequent offspring: a systematic review and meta-analysis

Purpose

History of fetal loss including miscarriage and stillbirth has been inconsistently associated with childhood (0–14 years) leukemia in subsequent offspring. A quantitative synthesis of the inconclusive literature by leukemia subtype was therefore conducted.

Methods

Eligible studies (N?=?32) were identified through the screening of over 3500 publications. Random-effects meta-analyses were conducted on the association of miscarriage/stillbirth history with overall (AL; 18,868 cases/35,685 controls), acute lymphoblastic (ALL; 16,150 cases/38,655 controls), and myeloid (AML; 3042 cases/32,997 controls) leukemia. Sensitivity and subgroup analyses by age and ALL subtype, as well as meta-regression were undertaken.

Results

Fetal loss history was associated with increased AL risk [Odds Ratio (OR) 1.10, 95% Confidence Intervals (CI) 1.04–1.18]. The positive association was seen for ALL (OR 1.12, 95%CI 1.05–1.19) and for AML (OR 1.13, 95%CI 0.91–1.41); for the latter the OR increased in sensitivity analyses. Notably, stillbirth history was significantly linked to ALL risk (OR 1.33, 95%CI 1.02–1.74), but not AML. By contrast, the association of ALL and AML with previous miscarriage reached marginal significance. The association of miscarriage history was strongest in infant ALL (OR 2.34, 95%CI 1.19–4.60).

Conclusions

In this meta-analysis involving >50,000 children, we found noteworthy associations by indices of fetal loss, age at diagnosis, and leukemia type; namely, of stillbirth with ALL and miscarriage history with infant ALL. Elucidation of plausible underlying mechanisms may provide insight into leukemia pathogenesis and indicate monitoring interventions prior to and during pregnancy.

     

High concordance of subtypes of childhood acute lymphoblastic leukemia within families: lessons from sibships with multiple cases of leukemia

Polymorphic genes have been linked to the risk of acute lymphoblastic leukemia (ALL). Surrogate markers for a low burden of early childhood infections are also related to increased risk for developing childhood ALL. It remains uncertain, whether siblings of children with ALL have an increased risk of developing ALL. This international collaboration identified 54 sibships with two (N = 51) or more (N = 3) cases of childhood ALL (ages <18 years). The 5-year event-free survival for 61 patients diagnosed after 1 January 1990 was 0.83 ± 0.05. Ages at diagnosis (Spearman correlation coefficient, r(S) = 0.41, P = 0.002) were significantly correlated, but not WBCs (r(S) = 0.23, P = 0.11). In 18 sibships with successful karyotyping in both cases, six were concordant for high-hyperdiploidy (N = 3), t(12;21) [ETV6/RUNX1] (N = 1), MLL rearrangement (N = 1) or t(1;19)(q23/p13) (N = 1). Eleven sibships were ALL-subtype concordant, being T-cell ALL (T-ALL) (N = 5, of a total of six sibships, where the first-born had T-ALL) or B-lineage ALL belonging to the same cytogenetic subset (N = 6), a finding that differs significantly from the expected chance distribution (κ: 0.58; P < 0.0001). These data indicate strong genetic and/or environmental risk factors for childhood ALL that are restricted to specific ALL subtypes, which must be taken into account, when performing epidemiological studies to reveal etiological factors.     

Maternal prenatal intake of one-carbon metabolism nutrients and risk of childhood leukemia

Purpose

Folate, vitamins B12 and B6, riboflavin, and methionine are critical nutrients for the one-carbon metabolism cycle involved in DNA synthesis and epigenetic processes. We examined the association between maternal intake of these nutrients before pregnancy and risk of childhood acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) in a matched case–control study.

Methods

Maternal dietary intake and vitamin supplement use in the year before pregnancy was assessed by food frequency questionnaire for 681 ALL cases, 103 AML cases, and 1076 controls. Principal component analysis was used to construct a variable representing combined nutrient intake, and conditional logistic regression estimated the odds ratio (OR) and 95% confidence interval (CI) for the association of ALL and AML with the principal component and each nutrient.

Results

Higher maternal intake of one-carbon metabolism nutrients from food and supplements combined was associated with reduced risk of ALL (OR for one-unit change in the principal component = 0.91, CI 0.84–0.99) and possibly AML (OR for the principal component = 0.83, CI 0.66–1.04). When analyzed separately, intake of supplements high in these nutrients was associated with a reduced risk of ALL in children of Hispanic women only.

Conclusions

In conclusion, these data suggest that higher maternal intake of one-carbon metabolism nutrients may reduce risk of childhood leukemia.

     

Genetic predisposition to acute lymphocytic leukemia in American blacks. A Pediatric Oncology Group study

Recent reports have shown an association between genes lying within the major histocompatibility complex (MHC), particularly HLA and factor B (Bf), and acute lymphocytic leukemia (ALL) in white children. The frequencies of Bf and complement component C4 phenotypes in 90 black American children with ALL were examined to determine if a genetic association existed. The Bf and C4 results for the black children with ALL were compared with frequencies in healthy black Americans from the same geographic region. The BfF allele was carried by 95.6% of the black ALL patients compared with 86.1% of the controls (P = 0.017; relative risk = 3.5). In contrast, only 2.2% of the patients with ALL were homozygous for BfS compared with 9.8% of the controls (P = 0.043; relative risk = 0.2). These findings are similar to those observed in white American children. The C4A6 phenotype was found in 11.9% of the black children with ALL compared with 0.6% of the controls (P = 0.0026; relative risk = 22.7). These findings represent the first reported association of a particular allele whose gene lies within the MHC with ALL in black American children. The results suggest that the occurrence of ALL in black American children may be partially due to a genetic influence.     

Glucocorticoid receptor in childhood acute lymphoblastic leukemia

Glucocorticoid(GC)hasbeenusedinthetreatmentofchildhoodacutelymphoblasticleukenda(ALL)formanyyears.IthasprovedthattheeffectofGCismediatedthroughaglucocortic0idreceptor(GCR)ofthetargetcell.[1]Therefore,manyexpertshaveconcentratdtheirattentiononGCR,butthereisnoreportonthestudyofGCRinchildho0dALLinChina.InununologicalclassificationofALLmaydifferentiatethecelloriginandclustersofdifferentiation(CD)inleukendacell.Itisoneoftheimportantindicatorstoguidecombinationchemotherapyandt0makeapr0gnos…     

Safe lumbar puncture under analgo-sedation in children with acute lymphoblastic leukemia

Background

Children with acute lymphoblastic leukemia (ALL) undergo multiple lumbar punctures (LPs) during their course of treatment for diagnostic and therapeutic purposes. LP is a stressful and painful procedure, affecting the quality of life of these children. Procedural analgo-sedation might improve the child’s comfort and prevent the child’s movements, reducing the risk of traumatic lumbar puncture with blasts (TLP+), mainly at diagnosis, when higher numbers of blast cells are circulating in the peripheral blood. The aim of this study was to evaluate the safety and efficacy of procedural analgo-sedation in children with ALL.

Methods

From September 2006 to November 2008, we performed a total of 252 lumbar punctures under deep sedation with propofol and ketamine in 25 children with ALL treated at our division. During the procedures, vital parameters were monitored and side effects were recorded. The efficacy of deep sedation was evaluated using Ramsay and Children’s Hospital Eastern Ontario Pain scales. Cerebrospinal fluid was collected for chemical and cytological examinations.

Results

In all patients a satisfactory sedation and analgesia were achieved. The evaluation of vital parameters did not show any significant variation compared to baseline values. No side effects were recorded. Only 3 (1.2 %) of 252 lumbar punctures resulted in traumatic effects.

Conclusion

To strongly improve comfort and quality of life of children with ALL and reduce the risk of TLP+ mainly at diagnosis, we recommend performing the lumbar punctures under analgo-sedation because it is a safe and effective procedure.     

谷胱甘肽转移酶P1基因多态性与儿童ALL HD-MTX不良反应的关系

  目的  研究谷胱甘肽转移酶P1(glutathione S-transferase pi, GSTP1)基因多态性与儿童急性淋巴细胞白血病(acute lymphoblastic leukemia, ALL)使用大剂量甲氨蝶呤(high-dose methotrexate, HD-MTX)化疗后不良反应的关系。  方法  应用巢式PCR (Nest PCR)、变性梯度凝胶电泳(denaturing gel gradient electrophoresis, DGGE)和DNA直接测序技术检测51例儿童ALL GSTP1基因型和等位基因分布频率, 按美国国立癌症研究所的常规毒性判定标准(NCICTCAE)对HD-MTX不良反应进行统计分析。  结果  筛查出3个GSTP1 SNPs位点即rs1695(A313G)、rs1138272(G439T)和rs4891(T555C)。rs1695/rs4891多态性位点包括32例(62.7%)野生型、16例(31.4%)杂合型和3例(5.9%)纯合型, rs1138272多态性位点仅包括1例(2.0%)杂合型和1例(2.0%)纯合型。3个SNPs位点等位基因频率分别为21.6%、2.9%和21.6%。GSTP1 rs1695/rs4891多态性位点中AG+GG/TC+CC基因型与外周血血红蛋白减少有关(OR=0.25, 95% CI=0.06~1.00, P=0.049), GSTP1 rs1695/rs4891多态性位点中AG+GG/TC+CC基因型与高危组患儿胃肠毒性发生有关(OR=0.125, 95% CI=0.02~0.78, P=0.026)。  结论  GSTP1 rs1695/rs4891多态性与ALL儿童HD-MTX化疗后外周血血红蛋白降低以及中高危组ALL儿童发生胃肠毒性有关。      

Genetic variants in the folate pathway and risk of childhood acute lymphoblastic leukemia

Objective

Folate is involved in the one-carbon metabolism that plays an essential role in the synthesis, repair, and methylation of DNA. We examined whether child??s germline genetic variation in the folate pathway is associated with childhood acute lymphoblastic leukemia (ALL), and whether periconception maternal folate and alcohol intake modify the risk.

Methods

Seventy-six single nucleotide polymorphisms (SNPs), including 66 haplotype-tagging SNPs in 10 genes (CBS, DHFR, FOLH1, MTHFD1, MTHFR, MTR, MTRR, SHMT1, SLC19A1, and TYMS), were genotyped in 377 ALL cases and 448 controls. Log-additive associations between genotypes and ALL risk were adjusted for age, sex, Hispanic ethnicity (when appropriate), and maternal race.

Results

Single and haplotype SNPs analyses showed statistically significant associations between SNPs located in (or adjacent to) CBS, MTRR, TYMS/ENOFS, and childhood ALL. Many regions of CBS were associated with childhood ALL in Hispanics and non-Hispanics (p < 0.01). Levels of maternal folate intake modified associations with SNPs in CBS, MTRR, and TYMS.

Conclusion

Our data suggest the importance of genetic variability in the folate pathway and childhood ALL risk.     

Genetic susceptibility to childhood acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is the most common pediatric cancer. The origin of this disease can be explained by a combination of genetic susceptibility factors and environmental exposures. For the purpose of our study it can be considered as a complex disease, caused by the "carcinogenic" effect of the environment modified by a series of genes. In population, these genes tend to occur in allelic forms representing functional polymorphisms thus explaining inter-individual variability in cancer susceptibility. The latter can be evaluated more realistically in childhood ALL than in sporadic cancers of the adult because of its relatively short latency period. We asked therefore, the question about the role of genes controlling the efficiency of xenobiotics metabolism in childhood leukemogenesis. Xenobiotics (drugs and carcinogens) are excreted from the body after metabolic conversion by enzymes mediating oxidation activation (Phase I) and conjugation detoxificaton (Phase II). Functional variants of these enzymes, resulting from known DNA polymorphisms in the corresponding genes, were shown to influence the risk to a variety of solid tumours in adults. A case-control study on ALL patients and healthy controls in a French-Canadian population was carried out by examining the loci of Phase I, CYP1A1 and CYP2D6, as well as Phase II enzymes, GSTM1, GSTT1, NAT1 and NAT2. The NAT2 slow-acetylator, CYP1A1*2A and GSTM1 null genotypes were shown to be significant risk determinants of ALL (OR=1.6, 1.8 and 1.8, respectively), whereas, polymorphisms in CYP2D6 and GSTT1 genes did not seem to play an important role in the aetiology of ALL. Interestingly, the risk associated with NAT2 slow-acetylators was most apparent among males homozygous for NAT1*4 (OR=3.3) whereas girls carrying the CYP1A1*4 allele were significantly underrepresented in the patient group (OR=0.2). These findings point to a gender-specific effect of DNA variants which, at least in part, may explain why ALL is more prevalent among boys. To assess gene-gene interactions, NAT2 slow-acetylators were considered together with GSTM1 null genotypes and CYP1A1*2A alleles. The combined presence of two risk-elevating genotypes appeared to confer an increased risk of ALL among the carriers (OR=2.6). This risk was increased further (OR=3.3) when all three genotypes occurred in the same individuals indicating that the combination of susceptibility variants is more predictive of risk then either of them independently. The association of leukemogenesis in children with metabolising gene variants suggests causal relation to environmental exposures.     

In vitro drug-resistance profile in infant acute lymphoblastic leukemia in relation to age, MLL rearrangements and immunophenotype.

Acute lymphoblastic leukemia (ALL) in infants under 1 year is strongly associated with translocations involving 11q23 (MLL gene), CD10-negative B-lineage (proB) immunophenotype, and poor outcome. The present study analyses the relationship between age, MLL rearrangements, proB-lineage, and in vitro drug resistance determined using the MTT assay. Compared to 425 children aged over 1 year with common/preB (c/preB) ALL, the 44 infants were highly resistant to steroids (for prednisolone (PRED) more than 580-fold, P=0.001) and L-asparaginase (L-ASP) (12-fold, P=0.001), but more sensitive to cytarabine (AraC) (1.9-fold, P=0.001) and 2-chlorodeoxyadenosine (2-CdA) (1.7-fold, P<0.001). No differences were found for vincristine, anthracyclines, thiopurines, epipodophyllotoxines, or 4-hydroperoxy (HOO)-ifosfamide. ProB ALL of all ages had a profile similar to infant ALL when compared with the group of c/preB ALL: relatively more resistant to L-ASP and PRED (and in addition thiopurines), and more sensitive to AraC and 2-CdA. Age was not related to cellular drug resistance within the proB ALL group (<1 year, n=32, vs >/=1 year, n=19), nor within the MLL-rearranged ALL (<1 year, n=34, vs >/=1 year, n=8). The translocation t(4;11)(q21;q23)-positive ALL cases were more resistant to PRED (>7.4-fold, P=0.033) and 4-HOO-ifosfamide (4.4-fold, P=0.006) than those with other 11q23 abnormalities. The expression of P-glycoprotein, multidrug-resistance protein, and lung-resistance protein (LRP) was not higher in infants compared to older c/preB ALL patients, but LRP was higher in proB ALL and MLL-rearranged ALL of all ages. In conclusion, infants with ALL appear to have a distinct in vitro resistance profile with the proB immunophenotype being of importance. The role of MLL cannot be excluded, with the t(4;11) being of special significance, while age appears to play a smaller role.