OBJECTIVETo investigate mutations of anaplastic lymphoma kinase (ALK) in Chinese children with neuroblastoma (NB).

METHODSGenomic DNA was extracted from 22 cases of paraffin-embedding NB tumor tissues. Gene mutations in the exons 20-26 which were mutational hotspots of ALK were analyzed by PCR-DNA direct sequencing.

RESULTSA novel synonymous mutation C3586T (Leu1196Leu) and a known synonymous mutation C3375A (Gly1125Gly) were found and located at exon 23 and exon 21 of ALK respectively. There were 10 cases (46%) of known synonymous mutation C3375A in 22 cases of NB. The C3375A allelic frequency was 27%. No statistically significant correlation was found between mutation C3375A and clinical parameters of NB such as age, sex, metastasis and tumor differentiation. Mutation was not found in the other 5 exons.

CONCLUSIONSA novel ALK gene synonymous mutation C3586T was identified using PCR-DNA sequencing. A known mutation C3375A in ALK was successfully identified in children, and its incidence is not influenced by the clinical features of childhood NB.

Child ; Child, Preschool ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Mutation ; Neuroblastoma ; genetics ; Polymerase Chain Reaction ; Receptor Protein-Tyrosine Kinases ; genetics

OBJECTIVETo investigate the distribution of γ-glutamyl hydrolase gene (GGH) 452C/T genotype and allele frequency in children with acute leukemia (AL) and healthy children.

METHODSBone marrow samples from 92 children with AL and peripheral blood samples from 124 healthy children were obtained to prepare complementary DNAs (cDNAs). The cDNAs were analyzed for a GGH 452C/T polymorphism by reverse transcriptase-polymerase chain reaction-denaturing gradient gel electrophoresis (RT-PCR-DGGE) and direct sequencing.

RESULTSThe frequencies of the AL patients with TT, CT and CC genotypes were 2.2%, 13.0% and 84.8%, and the frequencies of the control children were 1.6%, 16.9% and 81.5%, respectively. There was no significant difference in GGH genotype or T allele frequency between the two groups (P> 0.05). However, the T allele frequency in Han Chinese children was significantly different from those reported in Japanese, Mexican and African-American populations.

CONCLUSIONThe frequency of 452C/T polymorphism of GGH gene in Han Chinese children has been determined. The results suggested that an ethnic difference may exist.

Acute Disease ; Base Sequence ; Child ; Child, Preschool ; Female ; Gene Frequency ; Genotype ; Humans ; Infant ; Infant, Newborn ; Leukemia ; enzymology ; genetics ; Male ; Polymorphism, Single Nucleotide ; gamma-Glutamyl Hydrolase ; genetics

Child, Preschool ; Female ; Humans ; Male ; Mucormycosis ; drug therapy ; etiology ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; complications ; Remission Induction

Orthodenticlehomeobox 1 (OTX1) overexpression had previously been associated with the progression of several tumors. The present study aimed to determine the expression and role of OTX1 in human hepatocellular carcinoma (HCC). The expression level of OTX1 was examined by quantitative real-time PCR (qRT-PCR) in 10 samples of HCC and paired adjacent non-cancerous tissues, and by immunohistochemistry (IHC) analysis in 128 HCC samples and matched controls. The relationship between OTX1 expression and the clinicopathological features werealso analyzed. Furthermore, the effects of OTX1 knockdown on cell proliferation and migration were determined in HCC cell lines. Axenograft mouse model was also established to investigate the role of OTX1 in HCC tumor growth. TheqRT-PCR and IHC analyses revealed that OTX1 was significantly elevated in HCC tissues compared with the paired non-cancerous controls. Expression of OTX1 was positively correlated with nodal metastasis status (P = 0.009) and TNM staging (P = 0.001) in HCC tissues. In addition, knockdown of OTX1 by shRNA significantly inhibited the proliferation and migration, and induced cell cycle arrest in S phase in vitro. Tumor growth was markedly inhibited by OTX1 silencing in the xenograft. Moreover, OTX1 silencing was causable for the decreased phosphorylation level of ERK/MAPK signaling. In conclusion, OTX1 contributes to HCC progression possibly by regulation of ERK/MAPK pathway. OTX1 may be a novel target for molecular therapy towards HCC.
Aged ; Animals ; Blotting, Western ; Carcinoma, Hepatocellular/metabolism/*pathology ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Disease Progression ; Female ; Gene Expression Regulation, Neoplastic ; Humans ; Immunohistochemistry ; Liver/metabolism/pathology ; Liver Neoplasms/metabolism/*pathology ; Lymphatic Metastasis ; MAP Kinase Signaling System ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Middle Aged ; Neoplasm Staging ; Otx Transcription Factors/antagonists & inhibitors/genetics/*metabolism ; Phosphorylation ; RNA Interference ; Real-Time Polymerase Chain Reaction ; S Phase Cell Cycle Checkpoints ; Transplantation, Heterologous

OBJECTIVETo study the association between methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and toxicities after high-dose methotrexate (HD-MTX) infusion in children with acute lymphocytic leukemia (ALL).

METHODSMTHFR variants in 52 children with ALL were determined by reverse transcriptase-polymerase chain reaction-denaturing gradient gel electrophoresis and sequencing. Toxicities of children who received HD-MTX chemotherapy were evaluated according to the National Cancer Institute-Common Toxicity Criteria (NCI-CTC).

RESULTSThe children carrying MTHFR 1298AC had a higher risk of developing thrombocytopenia compared with the carriers of the 1298 AA genotype (OR=13.7, 95%CI=1.18-159.36, P=0.036). There was no significant difference in HD-MTX chemotherapy-related adverse effects between the patients with different MTHFR C677T or G1793A genotypes.

CONCLUSIONSMTHFR A1298C polymorohism may associate with the toxicity of HD-MTX chemotherapy in children with ALL.

Antimetabolites, Antineoplastic ; adverse effects ; Child ; Child, Preschool ; Female ; Genotype ; Humans ; Male ; Methotrexate ; adverse effects ; Methylenetetrahydrofolate Reductase (NADPH2) ; genetics ; Polymorphism, Genetic ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; drug therapy ; genetics ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo assess whether polymorphisms of methylenetetrahydrofolate reductase (MTHFR) gene is associated with susceptibility to acute lymphoblastic leukemia (ALL) or acute myeloid leukemia (AML) in Chinese Han children.

METHODSThe study has included 87 patients with ALL, 22 patients with AML and 120 healthy controls. All subjects were analyzed with reverse transcriptase-polymerase chain reaction-denaturing gradient gel electrophoresis and sequencing.

RESULTSA 677CT genotype of the MTHFR gene was associated with decreased risk of ALL (OR=0.23, 95%CI: 0.07-0.79). However, MTHFR A1298C genotypes were not associated with the risk of either disease. 677TT/1298AA and 677CC/1298AC genotypes were associated with increased risk of ALL(OR=3.78, 95% CI: 1.38-10.40; OR=3.17, 95% CI: 1.18-8.53, respectively), whereas the genotype 677CT/1298AA was associated with susceptibility to AML (OR=0.23, 95% CI: 0.06-0.97).

CONCLUSIONOur data suggested that C677T polymorphism of MTHFR gene may increase the risk of childhood AML.

Acute Disease ; Base Sequence ; Child ; Child, Preschool ; Female ; Genetic Predisposition to Disease ; Genotype ; Humans ; Infant ; Leukemia ; diagnosis ; enzymology ; genetics ; Male ; Methylenetetrahydrofolate Reductase (NADPH2) ; genetics ; Molecular Sequence Data ; Polymorphism, Single Nucleotide

OBJECTIVETo explore 6-mercaptopurine (6-MP) treatment-related adverse reactions in children with acute lymphoblastic leukemia (ALL), and to assess the association between the polymorphisms of thiopurine methyltransferase (TPMT) gene and these 6-MP related toxicities.

METHODSTotal RNA was extracted from bone marrow samples of 46 children with ALL and was then reversed to cDNA. TPMT(*)1S and (*)3C were screened by denaturing gradient gel electrophoresis (DGGE) combining with DNA sequencing. Drug toxicities were classified according to national cancer institute-common toxicity criteria version 3.0 (NCI CTC 3.0). The relationship between TPMT gene polymorphisms and the adverse reactions of 6-MP treatment was analyzed.

RESULTSDuring the maintenance treatment period, 22% (10/46) of children discontinued 6-MP treatment because of serious adverse reactions. Two children with TPMT(*)3C genotypes presented severe adverse reactions, including 1 child with homozygotic mutation who had 6-MP dose-related myelosuppression and hepatotoxicity. The main side effects of 6-MP were myelosuppression, hepatotoxicity and gastrointestinal reaction. And there were no significant differences between TPMT(*)1S genotypes and severe myelosuppression or hepatotoxicity caused by 6-MP (P>0.05).

CONCLUSIONSTPMT(*)3C may correlate with severe adverse reactions caused by 6-MP.

Child ; Child, Preschool ; Female ; Humans ; Male ; Mercaptopurine ; adverse effects ; Methyltransferases ; genetics ; Polymorphism, Genetic ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; drug therapy ; genetics

Objective To investigate the distribution of methylenetetrahydrofolate reductase (MTHFR) gene G1793A genotype and allele frequency in children with acute leukemia (AL),and to analyze the association between MTHFR gene polymorphism and the risk of AL.Methods Bone marrow samples from 109 childhood patients with AL and peripheral blood samples from 120 control children were obtained to prepare complementary DNAs (cDNAs).The cDNAs were analyzed for MTHFR G1793A polymorphism by reverse transcriptase-polymerase chain reaction-denaturing gradient gel electrophoresis and sequencing.Results The frequencies of 1793 GG,GA and AA genotyp(s) in MTHFR of the AL patients,acute lymphoblastic leukaemia (ALL) patients,acute myeloid leukaemia (AML) patients and the control children were 83.5％,15.6％,0.9％ ;82.8％,16.1％,1.1％ ;86.4％,13.6％,0％ and 89.2％,7.5％,3.3％,respectively.While the A allele frequency of MTHFR G1793A in those group were 8.7％,9.2％,6.8％ and 7.1％,respectively.However,no significant difference was observed in MTHFR G1793A genotypes or A allele frequency between the patients and controls (all P ＞0.05).The MTHFR 1793 GA + AA genotype was linked with an increased risk of AL,ALL and AML (AL:OR =1.71,95％ CI:0.77-3.80,P =0.19;ALL:OR =2.00,95％ CI:0.85-4.49,P =0.12;AML:OR =1.36,95％CI:0.33-5.62,P =0.67),but no significant difference in our population(all P ＞ 0.05).The A allele frequency of MTHFR G1793A in the study was 7.9％,significantly different from those reported in Ashkenazi Jewish,African-American,Brazilian,Austrian,Irau and Harbin populations (all P ＜0.05).Conclusion MTHFR G1793A may be not a genetic susceptibility factor for pediatric AL,but may exhibit an ethnic difference.

Objective: This study aimed to evaluate the effects of 2 endoscopic spine surgeries on the biomechanical properties of normal and osteoporotic spines. Methods: Based on computed tomography images of a healthy adult volunteer, 6 finite element models were created. After validating the normal intact model, a concentrated force of 400 N and a moment of 7.5 Nm were exerted on the upper surface of L3 to simulate 6 physiological activities of the spine. Five types of indices were used to assess the biomechanical properties of the 6 models, range of motion (ROM), maximum displacement value, intervertebral disc stress, maximum stress value, and articular protrusion stress, and by combining them with finite element stress cloud. Results: In normal and osteoporotic spines, there was no meaningful change in ROM or disc stress in the 2 surgical models for the 6 motion states. Model N1 (osteoporotic percutaneous transforaminal endoscopic discectomy model) showed a decrease in maximum displacement value of 20.28% in right lateral bending. Model M2 (unilateral biportal endoscopic model) increased maximum displacement values of 16.88% and 17.82% during left and right lateral bending, respectively. The maximum stress value of L4–5 increased by 11.72% for model M2 during left rotation. In addition, using the same surgical approach, ROM, maximum displacement values, disc stress, and maximum stress values were more significant in the osteoporotic model than in the normal model. Conclusion In both normal and osteoporotic spines, both surgical approaches were less disruptive to the physiologic structure of the spine. Furthermore, using the same endoscopic spine surgery, normal spine biomechanical properties are superior to osteoporotic spines.

Objective: This study aimed to evaluate the effects of 2 endoscopic spine surgeries on the biomechanical properties of normal and osteoporotic spines. Methods: Based on computed tomography images of a healthy adult volunteer, 6 finite element models were created. After validating the normal intact model, a concentrated force of 400 N and a moment of 7.5 Nm were exerted on the upper surface of L3 to simulate 6 physiological activities of the spine. Five types of indices were used to assess the biomechanical properties of the 6 models, range of motion (ROM), maximum displacement value, intervertebral disc stress, maximum stress value, and articular protrusion stress, and by combining them with finite element stress cloud. Results: In normal and osteoporotic spines, there was no meaningful change in ROM or disc stress in the 2 surgical models for the 6 motion states. Model N1 (osteoporotic percutaneous transforaminal endoscopic discectomy model) showed a decrease in maximum displacement value of 20.28% in right lateral bending. Model M2 (unilateral biportal endoscopic model) increased maximum displacement values of 16.88% and 17.82% during left and right lateral bending, respectively. The maximum stress value of L4–5 increased by 11.72% for model M2 during left rotation. In addition, using the same surgical approach, ROM, maximum displacement values, disc stress, and maximum stress values were more significant in the osteoporotic model than in the normal model. Conclusion In both normal and osteoporotic spines, both surgical approaches were less disruptive to the physiologic structure of the spine. Furthermore, using the same endoscopic spine surgery, normal spine biomechanical properties are superior to osteoporotic spines.