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1.
J Pediatr Hematol Oncol ; 44(1): e152-e159, 2022 01 01.
Article in English | MEDLINE | ID: mdl-34133377

ABSTRACT

INTRODUCTION: Bloodstream infections (BSIs) cause treatment-related mortality in pediatric acute leukemia. We explored the potential of intestinal microbiota and fecal volatile organic compounds (VOCs) analyses to predict BSI. METHODS: In this case-control study, fecal samples of pediatric acute leukemia patients were collected. Microbiota composition and fecal VOC profiles of BSI cases and matched non-BSI controls were compared. RESULTS: In total, 6 patients were included, of which 1 developed BSI and 1 neutropenic fever. Both showed reduced microbial diversity and stability of Bacteroidetes. In the BSI case, Pantoea was identified 15 days before BSI. Significant differences in fecal VOC profiles were measured between the case and controls. CONCLUSION: Microbiota and fecal VOC could serve as biomarkers to predict BSI in pediatric leukemia.


Subject(s)
Feces , Gastrointestinal Microbiome , Leukemia, Myeloid, Acute , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Sepsis/blood , Adolescent , Child , Child, Preschool , Feces/chemistry , Feces/microbiology , Female , Humans , Leukemia, Myeloid, Acute/blood , Leukemia, Myeloid, Acute/microbiology , Male , Pilot Projects , Precursor Cell Lymphoblastic Leukemia-Lymphoma/blood , Precursor Cell Lymphoblastic Leukemia-Lymphoma/microbiology , Volatile Organic Compounds
2.
J Nucl Med ; 58(5): 711-716, 2017 May.
Article in English | MEDLINE | ID: mdl-27765855

ABSTRACT

Predictive tools for guiding therapy in children with brain tumors are urgently needed. In this first molecular drug imaging study in children, we investigated whether bevacizumab can reach tumors in children with diffuse intrinsic pontine glioma (DIPG) by measuring the tumor uptake of 89Zr-labeled bevacizumab by PET. In addition, we evaluated the safety of the procedure in children and determined the optimal time for imaging. Methods: Patients received 89Zr-bevacizumab (0.1 mg/kg; 0.9 MBq/kg) at least 2 wk after completing radiotherapy. Whole-body PET/CT scans were obtained 1, 72, and 144 h after injection. All patients underwent contrast (gadolinium)-enhanced MRI. The biodistribution of 89Zr-bevacizumab was quantified as SUVs. Results: Seven DIPG patients (4 boys; 6-17 y old) were scanned without anesthesia. No adverse events occurred. Five of 7 primary tumors showed focal 89Zr-bevacizumab uptake (SUVs at 144 h after injection were 1.0-6.7), whereas no significant uptake was seen in the healthy brain. In 1 patient, multiple metastases all showed positive PET results. We observed inter- and intratumoral heterogeneity of uptake, and 89Zr-bevacizumab uptake was present predominantly (in 4/5 patients) within MRI contrast-enhanced areas, although 89Zr-bevacizumab uptake in these areas was variable. Tumor targeting results were quantitatively similar at 72 and 144 h after injection, but tumor-to-blood-pool SUV ratios increased with time after injection (P = 0.045). The mean effective dose per patient was 0.9 mSv/MBq (SD, 0.3 mSv/MBq). Conclusion:89Zr-bevacizumab PET studies are feasible in children with DIPG. The data suggest considerable heterogeneity in drug delivery among patients and within DIPG tumors and a positive, but not 1:1, correlation between MRI contrast enhancement and 89Zr-bevacizumab uptake. The optimal time for scanning is 144 h after injection. Tumor 89Zr-bevacizumab accumulation assessed by PET scanning may help in the selection of patients with the greatest chance of benefit from bevacizumab treatment.


Subject(s)
Bevacizumab/pharmacokinetics , Brain Stem Neoplasms/diagnostic imaging , Brain Stem Neoplasms/metabolism , Glioma/diagnostic imaging , Glioma/metabolism , Molecular Imaging/methods , Vascular Endothelial Growth Factor A/metabolism , Adolescent , Biomarkers, Tumor/metabolism , Child , Child, Preschool , Female , Humans , Male , Positron-Emission Tomography/methods , Radioisotopes/pharmacokinetics , Radiopharmaceuticals/pharmacokinetics , Reproducibility of Results , Sensitivity and Specificity , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Zirconium/pharmacokinetics
3.
J Vis Exp ; (118)2016 12 09.
Article in English | MEDLINE | ID: mdl-28060337

ABSTRACT

Drug resistance remains a major problem in the treatment of cancer for both hematological malignancies and solid tumors. Intrinsic or acquired resistance can be caused by a range of mechanisms, including increased drug elimination, decreased drug uptake, drug inactivation and alterations of drug targets. Recent data showed that other than by well-known genetic (mutation, amplification) and epigenetic (DNA hypermethylation, histone post-translational modification) modifications, drug resistance mechanisms might also be regulated by splicing aberrations. This is a rapidly growing field of investigation that deserves future attention in order to plan more effective therapeutic approaches. The protocol described in this paper is aimed at investigating the impact of aberrant splicing on drug resistance in solid tumors and hematological malignancies. To this goal, we analyzed the transcriptomic profiles of several in vitro models through RNA-seq and established a qRT-PCR based method to validate candidate genes. In particular, we evaluated the differential splicing of DDX5 and PKM transcripts. The aberrant splicing detected by the computational tool MATS was validated in leukemic cells, showing that different DDX5 splice variants are expressed in the parental vs. resistant cells. In these cells, we also observed a higher PKM2/PKM1 ratio, which was not detected in the Panc-1 gemcitabine-resistant counterpart compared to parental Panc-1 cells, suggesting a different mechanism of drug-resistance induced by gemcitabine exposure.


Subject(s)
Drug Resistance, Neoplasm/genetics , Neoplasms/genetics , Protein Isoforms/genetics , Sequence Analysis, RNA , Carrier Proteins/genetics , DEAD-box RNA Helicases/genetics , DNA Methylation , Humans , Membrane Proteins/genetics , Protein Processing, Post-Translational , RNA , Thyroid Hormones/genetics , Thyroid Hormone-Binding Proteins
4.
EJNMMI Res ; 4(1): 8, 2014 Jan 28.
Article in English | MEDLINE | ID: mdl-24472395

ABSTRACT

BACKGROUND: Positron emission tomography (PET) scanning with [18 F]fluorodeoxyglucose (18 F-FDG) is a useful diagnostic and prediction tool in brain tumors, but its value in childhood diffuse intrinsic pontine glioma (DIPG) is still unclear. For interpretation of 18 F-FDG PET results in DIPG, uptake values of the normal pons of children of increasing ages are mandatory. The aim of this study was to determine 18 F-FDG standard uptake value ratios (SUVr) of the normal pons and to compare these to those of DIPG. METHODS: We studied 36 subjects with a normal, non-affected pons (aged 5 to 23 years) and 6 patients with DIPG (aged 4 to 17 years) who underwent 18 F-FDG PET scanning. Magnetic resonance imaging (MRI) was co-registered to define the regions of interest. SUVr and SUVrmax for the pons/cerebellum (SUVrp/c) and the pons/occipital lobe (SUVrp/o) were calculated. Independent-samples t tests and Mann-Whitney U tests were used to compare the mean SUVr and Pearson's test for correlations. RESULTS: For the normal pons, mean SUVrp/c and SUVrp/o were 0.65 (±0.054) and 0.51 (±0.056), respectively. No significant correlations were found between the SUVr of the normal pons and sex, age, nor pontine volume. A modest but statistically significant correlation was found between SUVr and post-injection time acquisition timing. For DIPG, mean SUVrp/c and SUVrp/o were 0.74 (±0.20) and 0.65 (±0.30), respectively, while mean SUVrp(max)/c and SUVrp(max)/o were 1.95 (±0.48) and 1.81 (±0.20), respectively. CONCLUSION: The SUVr of the unaffected pons are strikingly constant between children, irrespective of sex and age, and can therefore be well used as a reference value for 18 F-FDG PET studies in DIPG.

5.
Eur J Pediatr ; 172(1): 31-7, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22991098

ABSTRACT

Although complementary and alternative medicine (CAM) is widely used in the pediatric population, research on the use of these therapies in the pediatric oncology population is of mixed quality. In this multicenter survey, we investigated the prevalence of CAM use, possible determinants of use, and parental attitude towards communication and research on CAM therapies. The prevalence of CAM use in the past 12 months was assessed by using a questionnaire based on the European guidelines on CAM research, filled out by parents of children visiting pediatric oncology outpatient clinics of six academic hospitals in the Netherlands. The questionnaire consisted of 26 questions on the child's clinical status, CAM use, and attitude towards communication and research on CAM therapies. One hundred and twenty-two of 288 respondents (42.4 %) reported CAM use. The most frequently used categories were homeopathy (18.8 %) and dietary supplements (11.5 %). Female gender and parental CAM use were significant predictors for the use of CAM (p < 0.001). Only one third of the parents had discussed CAM use with their pediatric oncologist. More than 80 % of the respondents identified a need for information about CAM from their pediatrician and 85.7 % was positive towards research on CAM. Half of the parents were interested in participating in future CAM trials. Conclusion, with more than 40 % of parents of Dutch pediatric oncology patients providing complementary and alternative medicine to their child and with lacking evidence on efficacy and safety of most CAM modalities, there is a clear need for high-quality research in this field. This study shows that most parents have an open attitude towards CAM research and that almost half of the parents would consider participating in future CAM trials, paving the way for research on CAM and aiming for its evidence-based use in pediatric oncology.


Subject(s)
Complementary Therapies/statistics & numerical data , Neoplasms/therapy , Adolescent , Attitude to Health , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Netherlands/epidemiology , Parents , Prevalence , Prospective Studies , Surveys and Questionnaires , Young Adult
6.
Oncotarget ; 3(10): 1169-81, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23045411

ABSTRACT

Osteosarcoma (OS) is the most common primary malignant bone tumour in children and adolescents. Despite aggressive therapy, survival outcomes remain unsatisfactory, especially for patients with metastatic disease or patients with a poor chemotherapy response. Chemoresistance contributes to treatment failure. To increase the efficacy of conventional chemotherapy, essential survival pathways should be targeted concomitantly. Here, we performed a loss-of-function siRNA screen of the human kinome in SaOS-2 cells to identify critical survival kinases after doxorubicin treatment. Gene silencing of JNK-interacting-protein-1 (JIP1) elicited the most potent sensitisation to doxorubicin. This candidate was further explored as potential target for chemosensitisation in OS. A panel of OS cell lines and human primary osteoblasts was examined for sensitisation to doxorubicin using small molecule JIP1-inhibitor BI-78D3. JIP1 expression and JIP1-inhibitor effects on JNK-signalling were investigated by Western blot analysis. JIP1 expression in human OS tumours was assessed by immunohistochemistry on tissue micro arrays. BI-78D3 blocked JNK-signalling and sensitised three out of four tested OS cell lines, but not healthy osteoblasts, to treatment with doxorubicin. Combination treatment increased the induction of apoptosis. JIP1 was found to be expressed in two-thirds of human primary OS tissue samples. Patients with JIP1 positive tumours showed a trend to inferior overall survival. Collectively, JIP1 appears a clinically relevant novel target in OS to enhance the efficacy of doxorubicin treatment by means of RNA interference or pharmacological inhibition.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Bone Neoplasms/drug therapy , Doxorubicin/pharmacology , Drug Resistance, Neoplasm/genetics , Osteosarcoma/drug therapy , RNA, Small Interfering/genetics , Adaptor Proteins, Signal Transducing/antagonists & inhibitors , Adaptor Proteins, Signal Transducing/genetics , Adolescent , Antibiotics, Antineoplastic/pharmacology , Apoptosis/drug effects , Blotting, Western , Bone Neoplasms/genetics , Bone Neoplasms/mortality , Case-Control Studies , Cell Line, Tumor , Humans , Immunoenzyme Techniques , Immunoprecipitation , Neoplasm Staging , Osteoblasts/metabolism , Osteoblasts/pathology , Osteosarcoma/genetics , Osteosarcoma/mortality , Prognosis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Survival Rate , Tissue Array Analysis
7.
Pediatr Blood Cancer ; 59(1): 161-6, 2012 Jul 15.
Article in English | MEDLINE | ID: mdl-22271750

ABSTRACT

BACKGROUND: This study investigates the effect of using patient reported outcomes (PROs) about health-related quality of life (HRQOL) in clinical practice on the type and amount of psychosocial topics discussed during a paediatric oncology consultation. PROCEDURE: Children (N = 193) with cancer participated in a sequential cohort intervention study, with a control (no PRO was used) and intervention group (a PRO was used). For each child three consecutive consultations with the paediatric oncologist were audio recorded in order to assess the discussed psychosocial topics. One third of the audio recordings were qualitatively analysed. RESULTS: The type of the discussed psychosocial topics in the control and intervention group did not differ from each other. However, the discussion of psychosocial topics increased in the intervention group compared to the control group. In both groups, topics within the social domain occurred most frequently and topics regarding the emotional domain had the lowest incidence. CONCLUSIONS: PROs do not change the psychosocial content of communication. Paediatric oncologists already address psychosocial issues during the consultation, regardless of the use of a PRO. However, with a PRO available they address these issues more systematically and more often.


Subject(s)
Neoplasms/psychology , Quality of Life , Adolescent , Child , Child, Preschool , Cohort Studies , Female , Humans , Infant , Infant, Newborn , Male , Neoplasms/therapy
8.
Blood ; 118(13): 3645-56, 2011 Sep 29.
Article in English | MEDLINE | ID: mdl-21813447

ABSTRACT

Translocations involving nucleoporin 98kD (NUP98) on chromosome 11p15 occur at relatively low frequency in acute myeloid leukemia (AML) but can be missed with routine karyotyping. In this study, high-resolution genome-wide copy number analyses revealed cryptic NUP98/NSD1 translocations in 3 of 92 cytogenetically normal (CN)-AML cases. To determine their exact frequency, we screened > 1000 well-characterized pediatric and adult AML cases using a NUP98/NSD1-specific RT-PCR. Twenty-three cases harbored the NUP98/NSD1 fusion, representing 16.1% of pediatric and 2.3% of adult CN-AML patients. NUP98/NSD1-positive AML cases had significantly higher white blood cell counts (median, 147 × 109/L), more frequent FAB-M4/M5 morphology (in 63%), and more CN-AML (in 78%), FLT3/internal tandem duplication (in 91%) and WT1 mutations (in 45%) than NUP98/NSD1-negative cases. NUP98/NSD1 was mutually exclusive with all recurrent type-II aberrations. Importantly, NUP98/NSD1 was an independent predictor for poor prognosis; 4-year event-free survival was < 10% for both pediatric and adult NUP98/NSD1-positive AML patients. NUP98/NSD1-positive AML showed a characteristic HOX-gene expression pattern, distinct from, for example, MLL-rearranged AML, and the fusion protein was aberrantly localized in nuclear aggregates, providing insight into the leukemogenic pathways of these AMLs. Taken together, NUP98/NSD1 identifies a previously unrecognized group of young AML patients, with distinct characteristics and dismal prognosis, for whom new treatment strategies are urgently needed.


Subject(s)
Homeodomain Proteins/genetics , Intracellular Signaling Peptides and Proteins/physiology , Leukemia, Myeloid, Acute/diagnosis , Leukemia, Myeloid, Acute/genetics , Nuclear Pore Complex Proteins/physiology , Nuclear Proteins/physiology , Adolescent , Adult , Aged , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Biomarkers, Tumor/physiology , Child , Child, Preschool , Female , Gene Expression Profiling , Gene Expression Regulation, Leukemic , Genes, Homeobox , Histone Methyltransferases , Histone-Lysine N-Methyltransferase , Homeodomain Proteins/metabolism , Humans , Infant , Infant, Newborn , Intracellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism , Leukemia, Myeloid, Acute/classification , Leukemia, Myeloid, Acute/pathology , Male , Microarray Analysis , Middle Aged , Nuclear Pore Complex Proteins/genetics , Nuclear Pore Complex Proteins/metabolism , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Prognosis , Young Adult
9.
J Pediatr Hematol Oncol ; 33(6): e231-8, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21792029

ABSTRACT

Growth hormone deficiency (GHD), mostly after cranial radiotherapy (CRT), may lead to several negative effects. Young adult survivors of acute lymphoblastic leukemia (ALL) could benefit from GH therapy in different ways. Twenty ALL survivors (17.1 ± 4.3 y after diagnosis) with low bone mineral densities and/or low insulin-like growth factor-1 were included. Two of the 3 patients who only received chemotherapy had GHD. Of the 20 patients, 17 started with GH therapy and 14 completed the 2-year study period. At several time points, bone mineral density (BMD) was measured. Psychological functioning was assessed. At the start of the study, standard deviation scores of height, insulin-like growth factor-1, lumbar spine, and femoral neck BMD were all below -1. After 2 years of GH therapy, total body BMD and lean mass were significantly higher (P < 0.01 and P < 0.001, respectively), whereas the percentage fat was significantly lower (P < 0.02). Several psychological measures improved significantly after 2 years. In conclusion, GH therapy during 2 years in young adult survivors of childhood ALL did have a number of benefits, such as improvement of total body bone density and body composition. Results also suggest improvement of psychological well being. Furthermore, it also became clear that patients after chemotherapy alone should be tested for GHD.


Subject(s)
Bone Density/drug effects , Health Status , Human Growth Hormone/therapeutic use , Metabolic Networks and Pathways/drug effects , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Survivors , Adult , Child , Female , Humans , Male , Survival Rate , Treatment Outcome , Young Adult
11.
J Pediatr Hematol Oncol ; 32(3): 240-2, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20387265

ABSTRACT

We describe a male child with multifocal kaposiform hemangioendothelioma in the right and left cervical region with development of Kasabach-Merritt syndrome. Treatment with interferon-alpha resulted in a good but only temporary clinical response.He relapsed 3 times with regrowth of the right cervical tumor. Involvement of the liver is suspected, because normalization of the liver size followed after the treatment with interferon-alpha. The question remains whether the multiple osteolytic bone lesions also reflect kaposiform hemangioendothelioma localization.


Subject(s)
Hemangioendothelioma/diagnosis , Neoplasm Recurrence, Local/diagnosis , Skin Neoplasms/diagnosis , Antineoplastic Agents/therapeutic use , Child , Hemangioendothelioma/drug therapy , Humans , Interferon alpha-2 , Interferon-alpha/therapeutic use , Male , Neoplasm Recurrence, Local/drug therapy , Prognosis , Recombinant Proteins , Skin Neoplasms/drug therapy , Syndrome
12.
Health Qual Life Outcomes ; 6: 103, 2008 Nov 26.
Article in English | MEDLINE | ID: mdl-19036151

ABSTRACT

BACKGROUND: Glucocorticoids are important in the treatment of childhood acute lymphoblastic leukaemia (ALL). However, cyclic administration of high dose glucocorticoids may cause rapid and substantial changes in quality of life (QoL). The maintenance phase of the Dutch ALL-9 protocol consisted of alternating two weeks on and five weeks off dexamethasone (6 mg/m(2)/day). The present study was performed to assess the effect of dexamethasone on QoL during treatment for ALL according to this protocol. METHODS: In a multicentre prospective cohort study, QoL was assessed halfway (T1) and at the end of the two-year treatment (T2). A generic (Child Health Questionnaire) and disease specific (PedsQL cancer version) QoL questionnaire were used to assess QoL in two periods: on and off dexamethasone, respectively. RESULTS: 41 children (56% males) were evaluated, mean age at diagnosis was 5.6 years. The CHQ physical and psychosocial summary scores were significantly lower than population norms. At T1 and T2, overall QoL showed no significant change. However, regarding specific domains (pain, cognitive functioning, emotion/behaviour and physical functioning) QoL decreased over time. QoL was significantly more impaired during periods on dexamethasone. CONCLUSION: Dexamethasone was associated with decreased QoL. At the end of treatment, reported QoL during dexamethasone deteriorated even more on certain scales (pain, cognitive functioning, emotion/behaviour and physical functioning). Knowledge of the specific aspects of QoL is essential to improve counselling and coping in paediatric oncology. Adverse effects of specific drugs on QoL should be taken into account when designing treatment protocols.


Subject(s)
Antineoplastic Agents, Hormonal/adverse effects , Dexamethasone/adverse effects , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Quality of Life , Adolescent , Antineoplastic Agents, Hormonal/administration & dosage , Antineoplastic Agents, Hormonal/therapeutic use , Child , Child, Preschool , Dexamethasone/administration & dosage , Dexamethasone/therapeutic use , Female , Humans , Male , Netherlands , Observation , Prospective Studies , Statistics, Nonparametric , Surveys and Questionnaires
13.
J Pediatr Surg ; 43(9): 1630-5, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18778997

ABSTRACT

Three patients with stage 4S neuroblastoma without MYC-N amplification who progressed to stage 4 with persistent liver involvement, were treated with iodine 131-meta-iodobenzylguanidine therapy, chemotherapy, and surgery. Successive histologic examination of the liver showed differentiation of the tumor in 2 patients and fibrosis in the third. One patient died of brain metastases at the age of 30 months. The other 2 patients are alive at 50 and 44 months. Diffuse liver involvement in patients with stage 4 progression of previous stage 4S without MYC-N amplification may differentiate after treatment. The aim of this report is to draw attention to major liver surgery that it may not be necessary in tumors without MYC-N amplification, despite the persistence of lesions in the liver.


Subject(s)
Adrenal Gland Neoplasms/pathology , Liver Neoplasms/secondary , Liver Neoplasms/therapy , Neuroblastoma/secondary , Neuroblastoma/therapy , Disease Progression , Fatal Outcome , Female , Humans , Infant , Male , Neoplasm Staging , Neuroblastoma/pathology
14.
Haematologica ; 91(11): 1573-4, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17043024

ABSTRACT

Anthracyclines are effective in the treatment of leukemia, but their use is limited because of cardiotoxicity. Liposomal daunorubicin (L-DNR) is potentially less cardiotoxic than daunorubicin (DNR). We compared in vitro cytotoxicity in pediatric acute leukemia samples and found no significant differences between cytotoxicity of DNR and L-DNR.


Subject(s)
Daunorubicin/adverse effects , Leukemia, Myeloid, Acute/drug therapy , Adolescent , Child , Child, Preschool , Daunorubicin/administration & dosage , Female , Humans , Leukemia, Myeloid, Acute/pathology , Liposomes/administration & dosage , Male
15.
Blood ; 106(2): 717-20, 2005 Jul 15.
Article in English | MEDLINE | ID: mdl-15797993

ABSTRACT

We studied whether common polymorphisms in genes involved in folate metabolism affect methotrexate (MTX) sensitivity. Ex vivo MTX sensitivity of lymphoblasts obtained from pediatric patients with acute lymphoblastic leukemia (ALL; n = 157) was determined by the in situ thymidylate synthase inhibition assay after either continuous (21 hours; TSI(50, cont)) or short-term (3 hours; TSI(50, short)) MTX exposure. DNA was isolated from lymphoblasts obtained from cytospin slides. Polymorphisms in methylenetetrahydrofolate reductase (MTHFR 677C>T, MTHFR 1298A>C), methionine synthase (MTR 2756A>G), methionine synthase reductase (MTRR 66A>G), methylenetetrahydrofolate dehydrogenase (MTHFD1 1958G>A), serine hydroxymethyl transferase (SHMT1 1420C>T), thymidylate synthase (TS 2R3R), and the reduced folate carrier (RFC 80G>A) were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) or real-time PCR. Patients with the MTHFR 1298AC variant or the MTRR 66 G-allele showed decreased in vitro MTX sensitivity measured under both test conditions. SHMT1 1420TT homozygotes only showed decreased MTX sensitivity in the TSI(50, cont). In conclusion, polymorphisms in the folate-related genes MTHFR, MTRR, and SHMT1 are related to MTX resistance in pediatric patients with ALL.


Subject(s)
Antimetabolites, Antineoplastic/pharmacology , Folic Acid/genetics , Methotrexate/pharmacology , Polymorphism, Genetic , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Child , Drug Resistance, Neoplasm/genetics , Ferredoxin-NADP Reductase/genetics , Folic Acid/metabolism , Genetic Variation , Glycine Hydroxymethyltransferase/genetics , Humans , In Vitro Techniques , Methylenetetrahydrofolate Reductase (NADPH2)/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/metabolism
16.
Cancer ; 100(4): 773-82, 2004 Feb 15.
Article in English | MEDLINE | ID: mdl-14770434

ABSTRACT

BACKGROUND: Although the majority of children with acute lymphoblastic leukemia (ALL) are cured with combination chemotherapy containing methotrexate (MTX), drug resistance contributes to treatment failure for a substantial fraction of patients. The primary transporter for folates and MTX is the reduced folate carrier (RFC). Impaired drug transport is a documented mechanism of MTX resistance in patients with ALL; however, to the authors' knowledge it is not known whether inactivating RFC mutations are a contributing factor. METHODS: The authors devised a genomic polymerase chain reaction-single strand conformational polymorphism assay followed by sequencing and screened the entire RFC coding region for sequence alterations in DNA from 246 leukemia specimens from patients with diverse ethnic variation, 24 at the time of recurrence and the rest at the time of diagnosis. This cohort was comprised of 203 B-precursor ALL specimens (82.5%), 32 T-lineage ALL specimens (13%), and 11 acute myeloblastic leukemia specimens (4.5%). RESULTS: Of 246 DNA samples, only 3 diagnosis B-precursor ALL specimens (1.2%) were found to harbor alterations in the RFC gene, including heterozygous single nucleotide changes resulting in D56H and D522N substitutions in the first extracellular loop and the C-terminus of this transporter, respectively. The third sample had a sequence alteration in exon 3 that could not be identified because of the lack of availability of DNA. CONCLUSIONS: Whereas inactivating RFC mutations are a frequent mechanism of MTX resistance in human leukemia cell lines and in patients with osteosarcoma, they are not common and do not appear to play any significant role in intrinsic or acquired resistance to MTX in childhood leukemia. This is the first study of RFC mutations in multiple pediatric leukemia specimens.


Subject(s)
Antimetabolites, Antineoplastic/pharmacology , Carrier Proteins/genetics , Carrier Proteins/pharmacology , Membrane Transport Proteins , Methotrexate/pharmacology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Blotting, Northern , Child , DNA Mutational Analysis , Drug Resistance, Neoplasm , Humans , Osteosarcoma/drug therapy , Osteosarcoma/genetics , Polymerase Chain Reaction , Polymorphism, Genetic , Polymorphism, Single-Stranded Conformational , Reduced Folate Carrier Protein , Tumor Cells, Cultured
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