DNA index as prognostic factor in childhood acute lymphoblastic leukemia in the COG-TARGET database

Background

This study was aimed to evaluate the value of DNA index(DI) among pediatric acute lymphoblastic leukemia (ALL) treated on Children’s Oncology Group (COG) protocols between 2000 and 2015.

Methods

Retrospective study were analysis among pediatric ALL patients from the TARGET dataset.

Result

Totally, 1668 eligible pediatric patients were enrolled in this study. Of them, 993 are male and 675 are female with a median age of 7.6 years old. The median follow-up for those patients was 7.7 years (range 0.1–15.7 years). The probability of 15-year EFS and OS were reported to be 67.5 ± 3.1% and 78.3 ± 2.5%, respectively. BCR/ABL1 fusion gene affected the early treatment response and the survival of childhood ALL. Moreover, those patients with ETV6/RUNX1 fusion gene were also significantly associated with better EFS (HR = 0.6, 95% CI 0.4–0.8, P = 0.003) and OS (HR = 0.3, 95%CI 0.2–0.5, P < 0.001) compared to patients with no ETV6/RUNX1. On the contrary, BM NR on Day+ 29 showed a significant decrease in EFS (HR = 3.1, 95%CI 2.1–4.5, P < 0.001) and OS (HR = 1.7, 95%CI 1.1–2.8, P = 0.026).

Multivariate analysis showed that DI was significantly associated with better EFS and OS. The threshold effect of DI on poor outcome was significant after adjusting for potential confounders. The adjusted regression coefficient (Log RR) was 0.7 (95%CI 0.1–3.2, P = 0.597) for DI < 1.1 while 8.8 (95%CI 1.4–56.0, P = 0.021) for DI ≥ 1.2 and 0.0 (95%CI 0.0–0.8, P = 0.041) for 1.1 ≤ DI < 1.2. Generalized additive models revealed that the lowest rates of the adverse outcomes estimated to occur among DI between 1.1 and 1.2.

Conclusion

For those childhood ALL treated on COG protocols between 2000 and 2015, ETV6/RUNX1 and BM NR were closely related to the prognosis. Moreover, the DI between 1.1 and 1.2 can serve as a significant cut-point discriminating the risk group, which indicated a favourable prognostic factor.

Identification of novel CSNK2A1 variants and the genotype-phenotype relationship in patients with Okur-Chung neurodevelopmental syndrome: a case report and systematic literature review

De novo germline variants of the casein kinase 2α subunit (CK2α) gene (CSNK2A1) have been reported in individuals with the congenital neuropsychiatric disorder Okur-Chung neurodevelopmental syndrome (OCNS). Here, we report on two unrelated children with OCNS and review the literature to explore the genotype-phenotype relationship in OCNS. Both children showed facial dysmorphism, growth retardation, and neuropsychiatric disorders. Using whole-exome sequencing, we identified two novel de novo CSNK2A1 variants: c.479A>G p.(H160R) and c.238C>T p.(R80C). A search of the literature identified 12 studies that provided information on 35 CSNK2A1 variants in various protein-coding regions of CK2α. By quantitatively analyzing data related to these CSNK2A1 variants and their corresponding phenotypes, we showed for the first time that mutations in protein-coding CK2α regions appear to influence the phenotypic spectrum of OCNS. Mutations altering the ATP/GTP-binding loop were more likely to cause the widest range of phenotypes. Therefore, any assessment of clinical spectra for this disorder should be extremely thorough. This study not only expands the mutational spectrum of OCNS, but also provides a comprehensive overview to improve our understanding of the genotype-phenotype relationship in OCNS.

[Analysis of the influence of iron overload in glucose metabolism in thalassemia major patients]

Objective: This study aimed at determining the characteristics of the glucose homeostasis and its relationship with iron overload of the patients with β-thalassemia major (β-TM). Method: From Sun Yat-sen Memorial Hospital between January 2014 and December 2015, a total of 57 transfusion-dependent β-TM patients with 5-18 years old were enrolled in this study and fasting blood glucose(FBG) and insulin level, serum ferritin (SF), serum iron, transferrin, total iron binding capacity, unsaturated iron binding capacity were determined.Insulin resistance index (IRI), insulin sensitivity index and β-cell function index (BFI) were also estimated. Besides, in 36 patients cardiac T2* and liver T2* were estimated. Result: (1) Four patients(7%) with β-TM were diagnosed diabetes mellitus, and 14(24%) had impaired fasting glucose. (2) The incidence of abnormal glucose metabolism was significantly different according to levels of SF and degrees of the cardiac iron overload(χ(2)=9.737, P<0.05; χ(2)=17.027, P<0.05). It rose while the level of SF increased and the degree of cardiac iron overload aggravated. (3) The incidence of abnormal glucose level was not significantly different in cases with different degree of liver iron overload.The severe group of liver iron overload had significantly higher levels of INS, HOMA-βFI, HOMA-ISI, HOMA-βFI than the non-severe group (Z=-2.434, -2.515, F=8.658, all P<0.05), while no differences were found in the level of FBG, HOMA-βFI between two groups. (4) The result of logistic regression analysis indicated that the cardiac T2* was a significant predictor for the incidence of abnormal glucose metabolism in TM patients (P=0.035, OR=1.182%, 95%CI=1.048 to 1.332). Conclusion: The high prevalence of abnormal glucose metabolism in β-TM patients was mainly closely related with the internal iron overload, especially in organs.The cardiac T2* was an independent risk factor for the incidence of abnormal glucose metabolism in TM patients.

[Clinical phenotypes and copy number variations in children with microdeletion and microduplication syndromes: an analysis of 50 cases]

OBJECTIVE

To investigate the association between genotype and phenotype of microdeletion and microduplication syndromes (MMSs) and the pathogenesis of pathogenic copy number variations (CNVs).

METHODS

A total of 50 children with MMSs diagnosed by chromosomal microarray analysis (CMA) from June 2013 to September 2015 were enrolled, and the clinical manifestations and features of pathogenic CNVs were analyzed.

RESULTS

The main clinical manifestations of children with MMSs included mental retardation, developmental delay, short stature, and unusual facies, with the presence of abnormalities in multiple systems. There were 54 pathogenic CNVs in total, consisting of 36 microdeletion segments and 18 microduplication segments, with sizes ranging from 28 kb to 48.5 Mb (mean 13.86 Mb). Pathogenic CNVs often occurred in chromosomes X, 15, and 1.

CONCLUSIONS

The clinical manifestations of MMSs are not specific, and a genotype-first approach can be used for diagnosis. Mode of inheritance, type of recombination (deletion or duplication), size of segment, and functional genes included helps with the interpretation of CNVs of de novo mutations, and in-depth research on rare pathogenesis may become breakthrough points for the identification of new MMSs.

[Genetic instability in cancer tissues analyzed by RAPD PCR]

In five kinds of tumors, total 128 specimens were analyzed by RAPD (random amplified polymorphic DNA) PCR with nine 10-base arbitrary primers for detecting instabilities of DNA and chromosome and screening new molecular markers coupled to putative or unknown oncogenes and/or tumor suppressor genes. Bands representing instabilities have been recovered and purified from agarose and cloned into pCAPs vector, and further labeled by DIG as probes for analysis of Southern blot, Northern blot and Sequencing. Results revealed that sample 5 and 3 of the gastric cancers showed the highest genomic changes and the average detectability in five sorts of cancers was up to at least 40% (42.2%-49.4%), and that there were significant differences in the ability of each primer to detect genomic instability, which ranged from 27% to 68%. Despite the highest detectability of genetic instability (68%) in tumor tissues, primer 2 could produce stable profiles of DNA bands in normal tissue genome with good reproducibility. On the contrary, primer 8 was of the lowest one (27%). Band B of single copy found to be allelic losses in gastric and colon cancers according to RFLP analysis was of a novel sequence and registered by Gen-Bank (Accession Number AF151005). Therefore the genetic instabilities often concentrated on some special locuses of chromosome e.g. repetitive sequences etc. and coupled to carcinogenesis. It was impossible or difficult to get great achievements for cancer treatments with the procedure of gene therapy only to one oncogene or one tumor suppressor gene because the extensive DNA variations occurred during the progression of tumor. RAPD assay connected with other techniques was a good tool for the detection of genomic instabilities and direct screening of some new molecular markers related to tumor suppressor genes or oncogenes.

[Infection of mutated mouse complement receptor type II by Epstein-Barr virus]

Site-directed mutagenesis method was used to introduce two desired mutations, which were confirmed by DNA sequencing, into mouse complement receptor Type II gene(MCR2). Then the constructed eukaryotic expression vectors containing wild type mouse CR2/1(wtMCR2/1), mutant type mouse CR2/1 (mtMCR2/1) and human CR2 (hCR2) cDNA were transferred into mouse SP2/0 cells by electroporation. After two-week screening by G418, the stably transfected clones were obtained. Several ways including PCR, RT-PCR, and immunohistochemistry were utilized to screen those clones with interesting genes integrated and expressed. Then Epstein-Barr virus(EBV) was used to infect these transfected cells and EBER-1 (EBV encoded RNAs) hybridization results showed that only hCR2 and mtMCR2 transfected SP2/0 cells could be infected by EBV, but positive rate of the former was much higher than the latter. This study sets groundwork for elucidating the mechanism by which EBV enters the cells and for establishing the animal model of EBV-related nasopharyngeal carcinoma (NPC).

[Study on the molecular structure and function of protein kinase C isoenzyme]

Protein kinase C (PKC) is a serine/threonine kinase family consisting at least 11 related isoenzymes, and it can be divided into four distinct classes, conventional PKC (cPKCs), novel or new PKC (nPKCs), atypical PKC (aPKCs), and PKC-u. All PKC members contain conserved and variant amino acid sequences in ATP binding sites, phosporyl transfer region, pseudosubstrate region, and phorbol ester binding sites. PKC isoenzymes exhibit distinct tissue distribution and play a critical role in cellular events. This review mainly summarized the PKC effects on tumorigenesis, tumor invasion and metastasis, tumor multidrug resistance, differentiation and development of hematopoietic progenitor cells, and hormonal production and secretion.

[Hemodynamics in skin and tissue expansion]

The capillary blood flow (CBF) of the random flaps constructed on expanded and unexpanded skin of dogs was determined by radioactive microsphere technique. The CBF was significantly higher (P < 0.001) in the skin flaps of the expanded group (387 +/- 23 microliters/min/flap) than that of the acute group (127 +/- 16 microliters/min/flap). There were no significant differences in the expanded group, the delayed group (374 +/- 35 microliters/min/flap) and the control group (389 +/- 48 microliters/min/flap). Even at the pedicle site, the CBF of the acute group was already significantly lower than that of other three groups (P < 0.001). The general tendency of gradual CBF reduction from the pedicle to the distal end of all the flaps was observed. The CBF at the point 8cm from the pedicle of the acute group was 12 microliters/min/g, whereas in other three groups, at point 13 cm from the pedicle the CBF was 12 microliters/min/g. The results suggested that during skin expansion the area of skin is enlarged, and its CBF and survival length may be increased. The problem of capsulectomy during flap construction was discussed.