Williams-Beuren syndrome in pediatric T-cell acute lymphoblastic leukemia: A rare case report and review of literature.

BACKGROUND: Williams-Beuren syndrome (WBS) is a rare genetic disorder caused by hemizygous microdeletion of contiguous genes on chromosome 7q11.23. Although the phenotype features extensive heterogeneity in severity and performance, WBS is not considered to be a predisposing factor for cancer development. Currently, hematologic cancers, mainly Burkitt lymphoma, are rarely reported in patients with WBS. Here in, we report a unique case of T-cell acute lymphoblastic leukemia in a male child with WBS. METHODS: This retrospective study analyzed the clinical data of this case receiving chemotherapy were analyzed. This is a retrospective study. RESULTS: The patient, who exhibited a typical WBS phenotype and presented with hemorrhagic spots. Chromosomal genome-wide chip analysis (CMA) revealed abnormalities on chromosomes 7 and 9. The fusion gene STIL-TAL1 and mutations in BCL11B, NOTCH1, and USP7 have also been found and all been associated with the occurrence of T-cell leukemia. The patient responded well to the chemotherapy. CONCLUSION: To the best of our knowledge, this is the first reported case of WBS in T-cell acute lymphoblastic leukemia. We want to emphasize that the occurrence of leukemia in this patient might be related to the loss of 7q11.23 and microdeletion of 9p21.3 (including 3 TSGs), but the relationship between WBS and malignancy remains unclear. Further studies are required to clarify the relationship between WBS and malignancy.

Outcomes after HSCT for mucolipidosis II (I-cell disease) caused by novel compound heterozygous GNPTAB mutations.

Background: Mucolipidosis type II (MLII), or I-cell disease, is a rare lysosomal storage disease (LSD) caused by variants in the GNPTAB gene. MLII patients exhibit clinical phenotypes in the prenatal or neonatal stage, such as marked dysmorphic features, cardiac involvement, respiratory symptoms, dysostosis multiplex, severe growth abnormalities, and mental and motor developmental abnormalities. The median age at diagnosis for MLII is 0.7 years, the median survival is 5.0 years, and the median age at death is 1.8 years. No cure for MLII exists. Methods: Sanger sequencing of the GNPTAB gene identified the compound heterozygous mutations c.673C > T in exon 7 and c.1090C > T in exon 9, which were novel double heterozygous mutations first reported in China. For the first time, we describe our experience in the use of HSCT for MLII. Our patient underwent HSCT with cells from a 9/10 human leukocyte antigen (HLA)-matched unrelated donor at 12 months of age. Myeloid neutrophil and platelet engraftment occurred on Days 10 and 11, respectively. Results: The patient's limb muscle tension was significantly reduced, and his gross and fine motor skills were improved four months after transplantation. DST(Developmental Screen Test) results showed that the patient's fine motor skills and mental development were improved compared with before HSCT. Conclusion: MLII is a very severe lysosomal storage disease, to date, only 3 cases have been reported on the use of HSCT to treat MLII. Our data show that HSCT is a potential way to prolong the life of patients and improve their quality of life. Due to the lack of comparable data and time, the exact benefit remains unclear in MLII patients. Longer-term follow-up and in-depth prospective studies are indispensable.

"Sandwich" protocol based on modified SMILE regimen for children with newly extranodal NK/T cell lymphoma, nasal type: a single-arm, single-center clinical study.

Extranodal NK/T-cell lymphoma, nasal type (ENKTL), which is a rare form of mature T/NK cell lymphoma in children, currently lacks a standardized first-line treatment approach. However, a treatment protocol known as the "sandwich" regimen has been used in children newly diagnosed with ENKTL. This protocol combines the administration of methotrexate, ifosfamide, etoposide, pegaspargase, and dexamethasone (referred to as SMILE) with the addition of radiotherapy (RT). From September 2017 to December 2020, a total of five patients were included in the study, consisting of three males and two females. The median age of onset was 10.6 years (range, 9.8 to 14.0 years). Among the patients, four had nasal/nasopharyngeal disease at stage II, while one patient had extra nasal disease involving the skin at stage IV. The median EBV-DNA level in plasma was 1.68 × 103 copies/ml (range, 0.44 to 21.1 × 103copies/ml). All the patients had good overall response after 2 cycles of chemotherapy and radiotherapy, including 4 of the patients who had a complete response and 1 of the patients with partial remission. The patient with stage IV received allogeneic hematopoietic stem cell transplantation after the EBV-DNA level was elevated again during treatment. One patient in the low-risk group experienced grade 4 oral mucositis, while no other severe complications or treatment-related deaths were observed. The median follow-up period was 22 months (range, 5 to 57 months). All five patients successfully completed their treatment, with four patients achieving event-free survival, and one patient was lost to follow-up. The median OS time and EFS time was 33 months (range: 18-57 months) and 20 months (range: 5-47 months), respectively. The sandwich protocol has demonstrated a high response rate, good tolerance to chemotherapy, and no treatment-related fatalities. However, further confirmation is necessary through additional clinical studies involving larger sample sizes. Clinical trial registration number: Due to modified SMILE regimens with sandwiched radiotherapy yielded promising outcomes in children ENKTL, we have carried out a phase II multicenter clinical trial (ChiCTR220005954) for children ENKTL in China to further verify the efficacy and safety.

Measurement of the morphological data of primary teeth in northwest China.

Objective: This study aims to digitally obtain the morphological data of children's primary teeth in northwest China and evaluate the reliability of digitally obtaining the anatomical morphological data of primary teeth. Methods: A total of 308 extracted primary teeth and cone-beam computed tomography (CBCT) images of 407 primary teeth were collected in northwest China. Electronic digital Vernier callipers (accuracy: 0.01 mm) were used to measure the mesiodistal and buccolingual diameters and crown length of the extracted primary teeth and calculate the crown area and crown index. Each sample was scanned with an intraoral scanner (Trios2 3shape, Denmark), and the resulting stl format files were imported into Geomagic Wrap 2015 to measure the axial and buccolingual diameters and crown length. The crown area and crown index were then calculated. After verifying the accuracy of the CBCT image measurement, the CBCT image data of 407 samples were measured in SmartV software using the "measure length" function by referring to the coronal, sagittal, and horizontal planes to adjust the position of the reference line. Results: Northern Chinese have larger primary teeth than other populations (Japanese, white American, African, Icelander, Spanish, and Dominican Mestizo) but smaller primary teeth than native Australians. Compared to Indian primary teeth, northwest Chinese's primary teeth have larger diameters on the central axis and smaller diameters on the buccolingual surface. Male teeth are usually larger than female teeth. Compared with the results of Wang Huiyun's study, the axial and buccolingual diameters and crown length of all native tooth types in this total sample were significantly smaller at the 0.1% level, and only the axial diameters of the upper first molar and lower second molar and the crown length of the lower lateral incisor were significantly smaller at the 1% level. The results of the intraclass correlation coefficient of 308 extracted primary teeth expressed an excellent degree of agreement between the callipers and intraoral scanner for the following: mesiodistal diameter (0.956-0.991), buccolingual diameter (0.963-0.989), crown length [0.864-0.992, except for the upper canine (0.690)], crown index (0.850-0.975), and crown area (0.946-0.993). Conclusion: The digital measurements of the intraoral scanner and CBCT image are in good agreement with the manual measurement of the Vernier calliper. The difference between the anatomical morphology size of the primary teeth measured in this study and the results of different populations could be due to different genetic backgrounds and environmental factors.

[New methods to detect autophagic flux].

Autophagy is a crucial biological process of eukaryotes, which is involved in cell growth, survival and energy metabolism, while the premise of the autophagy function is activated autophagic flux. It has been confirmed that impaired autophagic flux promotes pathogenesis of many chronic inflammatory diseases, especially cancer, neurodegenerative disease and tissue fibrosis, therefore the analysis of autophagic flux state is important for revealing autophagy function and the mechanism of autophagy related diseases. Given that autophagy is a dynamic process with multiple steps, it is very hard to observe the real state of autophagic flux. Summarized here is the novel concept and current approach to detect autophagic flux. This knowledge is crucial for the researching of the biological function of autophagy, and may provide some strategies for developing autophagy-related drug.

[Research advances in the pathogenesis, diagnosis and treatment of hemophagocytic lymphohistiocytosis in children].

Hemophagocytic lymphohistiocytosis (HLH), or hemophagocytic syndrome (HPS), is characterized clinically by abrupt onset and progressive deterioration and even death. HLH is much more prevalent in children, and is potentially fatal if early diagnosis is not made and appropriate HLH-directed therapy not instituted. Increasing genetic defects and underlying diseases or causative factors have been identified to be closely implicated in the pathogenesis of HLH. In addition, great advances have been made in the past few years in terms of HLH diagnosis and clinical management. In the present review, the cause of disease, contemporary classification, epidemiology, genetic defects and molecular mechanisms, updated diagnostic criteria and novel treatment strategies for childhood HLH are summarized.

[DEDD decreases Smad3 activity, promotes tumor cell apoptosis and inhibits proliferation].

DEDD is a member of the death-effector domain protein family. DEDD inhibits the Smad3 mediated transcriptional activity and participates in the regulation of apoptosis. In this study, how the death-effector domain of DEDD participates in the regulation of Smad3 activity and apoptosis has been further investigated. Immunoblotting, immunofluorescence and immunoprecipitation had been used to detect the effects of the full length DEDD and its two truncated mutants, N-DEDD and C-DEDD on Smad3 subcellular distribution, phosphorylation, and interaction between Smad4. The effects of the full length DEDD and its two truncated mutants on cell apoptosis and proliferation had also been explored by flow cytometry and MTT assay. It showed that DEDD and N-DEDD inhibit TGF-beta1 induced Smad3 nuclear translocation and the formation of Smad3-Samd4 complex. DEDD and its two mutants can induce cell apoptosis and inhibit cell proliferation. These results suggested that DEDD inhibits the activity of Smad3 through its death-effector domain. Both the two truncated mutants of DEDD participate in the regulation of apoptosis and cell proliferation.

[Establishment and application of TLR2 receptor-based cell screening model].

TLR2 activity plays an important role in the pathogenesis of autoimmune diseases, tumor carcinogenesis and cardio-cerebrovascular diseases. To establish a TLR2 receptor-based cell screening model, NF-kappaB promoter-driven luciferase reporter plasmids were transfected into human embryonic kidney cells (HEK293) stably expressing human TLR2 and co-receptors CD14, TLR1 and TLR6. Single clones were then isolated and characterized. Using this screening system, a human TLR2-binding peptide C8 was obtained from the Ph.D.-7 Phage Display Peptide Library through biopanning and rapid analysis of selective interactive ligands (BRASIL). The binding characteristic of C8 with human TLR2 was evaluated by ELISA, flow cytometry and immunofluorescence. The NF-kappaB luciferase activity assay showed that C8 could activate the TLR2/TLR1 signaling pathway and induce the production of cytokines TNF-alpha and IL-6. In conclusion, the TLR2 receptor-based cell screening system is successfully established and a new TLR2-binding peptide is identified by using this system.

[Experimental study of donor natural killer cells reducing graft-versus-host disease and enhancing engraftment].

The purpose of this study was to investigate whether pretransplant infusion of reactive natural killer cells (NK cells) from donor or recipient can reduce graft-versus-host disease (GVHD) and enhance engraftment in bone marrow transplantation (BMT). Recipient BALB/c mice were divided into 4 groups after received 6.5 Gy total-body irradiation (TBI): control group 1 was treated with nothing, control group 2 received BMT alone, experiment group 1 received BMT and autoreactive NK cells, experiment group 2 received BMT and alloreactive NK cells. Life span, clinical and pathologic changes of GVHD and chimerism rate of each group were evaluated. The results showed that all mice were survival in control group 1. The life span was shorter in experiment group 1 than that in control group 2 (P < 0.05) and longer in experiment group 2 than that in control group 2 (P < 0.01). GVHD was higher in score of experiment group 1 than in control group 2 (P < 0.05) but lower in experiment group 2 than that in control group 2 (P < 0.01). The donor chimerism rate in both two experiment groups were higher than that in control group 2 (P < 0.05), however, the donor chimerism rate was higher in experiment group 2 than that in experiment group 1 (P < 0.01). It is concluded that pretransplant infusion of alloreactive donor NK cells can prolong life span, reduce the degree of GVHD and enhance engraftment. But autoreactive recipient NK cells can shorten life span, aggravate the degree of GVHD and also enhance engraftment, which is weaker than that using alloreactive donor NK cells.

[Immune regulatory effect of human bone marrow mesenchymal stem cells on T lymphocyte].

To investigate the immune regulatory effects of human bone marrow mesenchymal stem cells on alloantigen T lymphocyte in vitro, human MSCs were isolated and expanded from bone marrow cells, and identified with cell morphology, and the phenotypes were assessed by immunohistochemistry and flow cytometry. As the stimulation factor of T lymphocytes proliferation, either PHA or dendritic cells isolated from cord blood were cocultured with CD2(+) T lymphocytes from peripheral blood mononuclear cells by magnetic beads with or without MSC in 96-well plats for seven days. T cell proliferation was assessed by [(3)H]-thymidine incorporation using a liquid scintillation counter. T cell subsets, Th1, Th2, Tc1 and Tc2 were analyzed by flow cytometry after co-culture of CD2(+) T cells with MSCs for 10 days. The results showed that a significant decrease of CD2(+) T cell proliferation was evident when MSC were added back to T cells stimulated by DC or PHA, and an increase of Th2 and Tc2 subsets were observed after co-culture of MSC with T lymphocytes. It is suggested that allogeneic MSC can suppress T cell proliferation in vitro and the cause of that was partly depend on interaction of cells and the alteration of T cell subsets.

[Construction of eukaryotic expression vector of siRNA specific to bcr/abl fusion gene].

OBJECTIVE: To construct eukaryotic expression vector of siRNA specific to bcr/abl and to initially investigate the effect of recombinant plasmid on bcr/abl and P210 protein expression in K562 cells. METHODS: siRNA (small interfering RNA) was designed according to the Tuschl's principle of RNAi-based medicine, and was converted into cDNA coding expression of shRNA (small hairpin RNAs)of siRNA for bcr/abl fusion gene. The cDNA was synthesized and inserted into plasmid pTER. The pTER117 and pTER363 of recombinant plasmid being eukaryotic expression vector was controlled by the H1 promoter of RNA polymerase III, identified by the restriction map and the sequence analysis, and transfected into K562 cells by Lipofectamine. Expression of bcr/abl mRNA was assayed by RT-PCR; expression of P210 protein was detected by immunohistochemistry. RESULTS: The pTER117 and pTER363 of recombinant plasmid identified by the restriction map and the sequence analysis completely coincided with the designs. 24 hours after transfection in K562 cells, the recombinant plasmid could down regulate the expression of the bcr/abl mRNA and bcr/abl protein(P210) in K562 cells. CONCLUSION: The siRNA eukaryotic expression vector against bcr/abl mRNA has been successfully conctructed, and it effectively inhibits the expression of bcr/abl in K562 cells.

[A clinicopathological study of 96 cases of lymphoblastic lymphoma].

OBJECTIVE: To investigate the clinicopathological and immunohistochemical features of lymphoblastic lymphoma (LBL). METHODS: A retrospective clinicopathological study of 96 cases LBL was carried out. Immunohistochemical staining was used for the characterization and immunophenotyping. RESULTS: The patients age ranged from 4 to 72 years, with a median of 16 years, 69 patients were male and 27 female. Seventy-three cases had superficial or multi-lymphoadenopathy and 31 of them had mediastinal masses. Bone marrow was involved in 15 cases. Seventy-three cases were in clinical stages III and IV. The median survival of the followed-up patients was 5.5 (2 approximately 120) months. TdT and CD99 positive reactions were 75.0% and 92.7%, respectively. Of the 96 cases, 78 displayed T-cell marker positivity and 18 B-cell markers. 82.1% of the patients younger than 30 years of age had significantly higher incidences of T-LBL (64 patients), and 93.6% of the patients with mediastinal masses expressed T-cell markers. The poor prognostic factors were T-cell tumors, clinical stages III and IV, Ki-67 PI < 80% and no chemotherapy (P < 0.01). CONCLUSION: In children and young males, mediastinal masses with superficial or multi-lymphoadenopathy favors the diagnosis of LBL, but negative TdT reaction can not exclude this diagnosis. T-LBL is more common than B-LBL. Clinical stages, immunophenotypes and the level of Ki-67 expression were closely related with prognosis of LBL.