[Clinical study of 15 cases of primary non-immunodeficient central nervous system lymphoma in children]

Clinical data of 15 primary central nervous system lymphoma (PCNSL) children aged ≤18 years admitted to our hospital between May 2013 to May 2023 were retrospectively analyzed. Our goal was to summarize the clinical features of children and investigate the therapeutic effect of a high-dose methotrexate (HD-MTX) based chemotherapy regimen on this disease. The male-to-female ratio was 2.7∶1, and the median age was 7.2 (2.3-16.4) years at diagnosis. The initial clinical symptoms were primarily cranial hypertension, with imaging findings revealing multiple lesions. Pediatric PCNSL with normal immune function has a favorable prognosis with HD-MTX-based chemotherapy. Patients with a stable disease can be treated with minimal or no maintenance. HD-MTX-based chemotherapy remains effective when the disease progresses or recurs after an initial course of non-HD-MTX-based chemotherapy.

Epigenetic implications in maternal diabetes and metabolic syndrome-associated risk of orofacial clefts

Orofacial clefts (OFCs) are one of the most common types of structural birth defects. The etiologies are complicated, involving with genetic, epigenetic, and environmental factors. Studies have found that maternal diabetes and metabolic syndrome are associated with a higher risk of OFCs in offspring. Metabolic syndrome is a clustering of several disease risk factors, including hyperglycemia, dyslipidemia, obesity, and hypertension. Metabolic disease during pregnancy can increase risk of adverse outcomes and significantly influence fetal development, including orofacial formation and fusion. An altered metabolic state may contribute to developmental disorders or congenital defects including OFCs, potentially through epigenetic modulations, such as histone modification, DNA methylation, and noncoding RNA expression to alter activities of critical morphogenetic signaling or related developmental genes. This review summarizes the currently available evidence and underlying mechanisms of how the maternal metabolic syndrome is associated with OFCs in mostly human and some animal studies. It may provide a better understanding of the interactions between intrauterine metabolic status and fetal orofacial development which might be applied toward prevention and treatments of OFCs.

Ezh2-dependent methylation in oral epithelia promotes secondary palatogenesis

BACKGROUND

In addition to genomic risk variants and environmental influences, increasing evidence suggests epigenetic modifications are important for orofacial development and their alterations can contribute to orofacial clefts. Ezh2 encodes a core catalytic component of the Polycomb repressive complex responsible for addition of methyl marks to Histone H3 as a mechanism of repressing target genes. The role of Ezh2 in orofacial clefts remains unknown.

AIMS

To investigate the epithelial role of Ezh2-dependent methylation in secondary palatogenesis.

METHODS

We used conditional gene-targeting methods to ablate Ezh2 in the surface ectoderm-derived oral epithelium of mouse embryos. We then performed single-cell RNA sequencing combined with immunofluorescence and RT-qPCR to investigate gene expression in conditional mutant palate. We also employed double knockout analyses of Ezh1 and Ezh2 to address if they have synergistic roles in palatogenesis.

RESULTS

We found that conditional inactivation of Ezh2 in oral epithelia results in partially penetrant cleft palate. Double knockout analyses revealed that another family member Ezh1 is dispensable in orofacial development, and it does not have synergistic roles with Ezh2 in palatogenesis. Histochemistry and single-cell RNA-seq analyses revealed dysregulation of cell cycle regulators in the palatal epithelia of Ezh2 mutant mouse embryos disrupts palatogenesis.

CONCLUSION

Ezh2-dependent histone H3K27 methylation represses expression of cell cycle regulator Cdkn1a and promotes proliferation in the epithelium of the developing palatal shelves. Loss of this regulation may perturb movement of the palatal shelves, causing a delay in palate elevation which may result in failure of the secondary palate to close altogether.

[Clinical study of mature B-cell lymphoma in 11 children with chromosome 11 long-arm abnormalities]

Objective: To explore the clinical, pathological, diagnostic, treatment, and prognostic features of children with mature B-cell lymphoma (MBCL) . Methods: This retrospective study included pediatric patients with MBCL with chromosome 11 long-arm abnormalities who were diagnosed and treated at our hospital from December 2018 to February 2023. Results: Among the 11 pediatric patients with MBCL, nine were male and two were female, with a median age of 9 (2-13) years and a median disease course of 1.8 (0.5-24) months. The clinical manifestations were cervical lymph node enlargement in four patients, nasal congestion and snoring in four patients, abdominal pain in two patients, and difficulty breathing in one patient. There were seven cases of Burkitt's lymphoma, two of follicular lymphoma, and two of advanced B-cell lymphoma according to the pathological morphology examination. No patients had central nervous system or bone marrow involvement, and no extensive metastasis was observed on B-ultrasound or positron emission tomography-computed tomography (PET/CT). One patient had a huge tumor lesion. The Revised International Pediatric Non-Hodgkin Lymphoma Staging System classified four patients as stage Ⅱ, five as stage Ⅲ, and two as stage Ⅳ. 11q probe detection showed five cases of 11q gain, three of 11q loss, and three of both gain and loss. FISH showed positive MYC expression in three patients, including eight with advanced B-cell lymphoma with 11q abnormalities and three with Burkitt's lymphoma with 11q abnormalities. According to the 2019 edition of the National Health Commission's diagnostic and treatment guidelines for invasive MBCL in children, one patient was classified as Group A, two as Group B, and eight as Group C. Early evaluation of the efficacy showed complete remission. After mid-term evaluation, the intensity of chemotherapy was reduced in Group B and Group C. Among two cases of chemotherapy, the remaining nine cases had a median follow-up of 32 (6-45) months, and none had event-related survival. Conclusion: The incidence of MBCL with 11q abnormalities in children is low, clinical symptoms are mild, and progression is slow. The absence of MYC, BCL2, BCL6 rearrangements, C-MYC negative and 11q abnormalities on FISH is an important diagnostic indicator, and reducing the intensity of chemotherapy can improve prognosis.

Canonical Wnt signaling is not required for Tgfb3 expression in the basal medial edge epithelium during palatogenesis

The secondary palate forms from two lateral primordia called the palatal shelves which form a contact in the midline, become adherent at the fusing interface (medial edge epithelia, MEE) and subsequently fuse. The gene encoding transforming growth factor-ß3 (Tgfb3) is strongly and specifically expressed in MEE cells. Our previous study suggested that Tgfb3 expression is controlled via upstream cis-regulatory elements in and around the neighboring Ift43 gene. Another study suggested that the canonical Wnt signaling via ß-Catenin is responsible for the MEE-specific Tgfb3 gene expression, since deletion of the Ctnnb1 gene by a commonly used Keratin 14-Cre (K14Cre) mouse line almost completely abolished Tgfb3 expression in the MEE resulting in cleft palate. Here, we wanted to analyze whether Tcf/Lef consensus binding sites located in the previously identified regions of the Ift43 gene are responsible for the spatiotemporal control of Tgfb3 expression during palatogenesis. We show that contrary to the previous report, deletion of the Ctnnb1 gene in basal MEE cells by the K14Cre driver (the same K14Cre mouse line was used as in the previous study referenced above) does not affect the MEE-specific Tgfb3 expression or TGFß3-dependent palatal epithelial fusion. All mutant embryos showed a lack of palatal rugae accompanied by other craniofacial defects, e.g., a narrow snout and a small upper lip, while only a small subset (<5%) of Ctnnb1 mutants displayed a cleft palate. Moreover, the K14Cre:Ctnnb1 embryos showed reduced levels and altered patterns of Shh expression. Our present data imply that epithelial ß-catenin may not be required for MEE-specific Tgfb3 expression or palatal epithelial fusion.

[Mid-term efficacy of China Net Childhood Lymphoma-mature B-cell lymphoma 2017 regimen in the treatment of pediatric Burkitt lymphoma]

Objective: To analyze the clinical characteristics of children with Burkitt lymphoma (BL) and to summarize the mid-term efficacy of China Net Childhood Lymphoma-mature B-cell lymphoma 2017 (CNCL-B-NHL-2017) regimen. Methods: Clinical features of 436 BL patients who were ≤18 years old and treated with the CNCL-B-NHL-2017 regimen from May 2017 to April 2021 were analyzed retrospectively. Clinical characteristics of patients at disease onset were analyzed and the therapeutic effects of patients with different clinical stages and risk groups were compared. Survival analysis was performed by Kaplan-Meier method, and Cox regression was used to identify the prognostic factors. Results: Among 436 patients, there were 368 (84.4%) males and 68 (15.6%) females, the age of disease onset was 6.0 (4.0, 9.0) years old. According to the St. Jude staging system, there were 4 patients (0.9%) with stage Ⅰ, 30 patients (6.9%) with stage Ⅱ, 217 patients (49.8%) with stage Ⅲ, and 185 patients (42.4%) with stage Ⅳ. All patients were stratified into following risk groups: group A (n=1, 0.2%), group B1 (n=46, 10.6%), group B2 (n=19, 4.4%), group C1 (n=285, 65.4%), group C2 (n=85, 19.5%). Sixty-three patients (14.4%) were treated with chemotherapy only and 373 patients (85.6%) were treated with chemotherapy combined with rituximab. Twenty-one patients (4.8%) suffered from progressive disease, 3 patients (0.7%) relapsed, and 13 patients (3.0%) died of treatment-related complications. The follow-up time of all patients was 24.0 (13.0, 35.0) months, the 2-year event free survival (EFS) rate of all patients was (90.9±1.4) %. The 2-year EFS rates of group A, B1, B2, C1 and C2 were 100.0%, 100.0%, (94.7±5.1) %, (90.7±1.7) % and (85.9±4.0) %, respectively. The 2-year EFS rates was higher in group A, B1, and B2 than those in group C1 (χ²=4.16, P=0.041) and group C2 (χ²=7.21, P=0.007). The 2-year EFS rates of the patients treated with chemotherapy alone and those treated with chemotherapy combined with rituximab were (79.3±5.1)% and (92.9±1.4)% (χ²=14.23, P<0.001) respectively. Multivariate analysis showed that stage Ⅳ (including leukemia stage), serum lactate dehydrogenase (LDH)>4-fold normal value, and with residual tumor in the mid-term evaluation were risk factors for poor prognosis (HR=1.38,1.23,8.52,95%CI 1.05-1.82,1.05-1.43,3.96-18.30). Conclusions: The CNCL-B-NHL-2017 regimen show significant effect in the treatment of pediatric BL. The combination of rituximab improve the efficacy further.

Human-specific gene CT47 blocks PRMT5 degradation to lead to meiosis arrest

Exploring the functions of human-specific genes (HSGs) is challenging due to the lack of a tractable genetic model system. Testosterone is essential for maintaining human spermatogenesis and fertility, but the underlying mechanism is unclear. Here, we identified Cancer/Testis Antigen gene family 47 (CT47) as an essential regulator of human-specific spermatogenesis by stabilizing arginine methyltransferase 5 (PRMT5). A humanized mouse model revealed that CT47 functions to arrest spermatogenesis by interacting with and regulating CT47/PRMT5 accumulation in the nucleus during the leptotene/zygotene-to-pachytene transition of meiosis. We demonstrate that testosterone induces nuclear depletion of CT47/PRMT5 and rescues leptotene-arrested spermatocyte progression in humanized testes. Loss of CT47 in human embryonic stem cells (hESCs) by CRISPR/Cas9 led to an increase in haploid cells but blocked the testosterone-induced increase in haploid cells when hESCs were differentiated into haploid spermatogenic cells. Moreover, CT47 levels were decreased in nonobstructive azoospermia. Together, these results established CT47 as a crucial regulator of human spermatogenesis by preventing meiosis initiation before the testosterone surge.

Single-cell transcriptomic signatures and gene regulatory networks modulated by Wls in mammalian midline facial formation and clefts

Formation of highly unique and complex facial structures is controlled by genetic programs that are responsible for the precise coordination of three-dimensional tissue morphogenesis. However, the underlying mechanisms governing these processes remain poorly understood. We combined mouse genetic and genomic approaches to define the mechanisms underlying normal and defective midfacial morphogenesis. Conditional inactivation of the Wnt secretion protein Wls in Pax3-expressing lineage cells disrupted frontonasal primordial patterning, cell survival and directional outgrowth, resulting in altered facial structures, including midfacial hypoplasia and midline facial clefts. Single-cell RNA sequencing revealed unique transcriptomic atlases of mesenchymal subpopulations in the midfacial primordia, which are disrupted in the conditional Wls mutants. Differentially expressed genes and cis-regulatory sequence analyses uncovered that Wls modulates and integrates a core gene regulatory network, consisting of key midfacial regulatory transcription factors (including Msx1, Pax3 and Pax7) and their downstream targets (including Wnt, Shh, Tgfβ and retinoic acid signaling components), in a mesenchymal subpopulation of the medial nasal prominences that is responsible for midline facial formation and fusion. These results reveal fundamental mechanisms underlying mammalian midfacial morphogenesis and related defects at single-cell resolution.

The role of Lrp6-mediated Wnt/β-catenin signaling in the development and intervention of spinal neural tube defects in mice

Neural tube defects (NTDs) are among the common and severe birth defects with poorly understood etiology. Mutations in the Wnt co-receptor LRP6 are associated with NTDs in humans. Either gain-of-function (GOF) or loss-of-function (LOF) mutations of Lrp6 can cause NTDs in mice. NTDs in Lrp6-GOF mutants may be attributed to altered β-catenin-independent noncanonical Wnt signaling. However, the mechanisms underlying NTDs in Lrp6-LOF mutants and the role of Lrp6-mediated canonical Wnt/β-catenin signaling in neural tube closure remain unresolved. We previously demonstrated that β-catenin signaling is required for posterior neuropore (PNP) closure. In the current study, conditional ablation of Lrp6 in dorsal PNP caused spinal NTDs with diminished activities of Wnt/β-catenin signaling and its downstream target gene Pax3, which is required for PNP closure. β-catenin-GOF rescued NTDs in Lrp6-LOF mutants. Moreover, maternal supplementation of a Wnt/β-catenin signaling agonist reduced the frequency and severity of spinal NTDs in Lrp6-LOF mutants by restoring Pax3 expression. Together, these results demonstrate the essential role of Lrp6-mediated Wnt/β-catenin signaling in PNP closure, which could also provide a therapeutic target for NTD intervention through manipulation of canonical Wnt/β-catenin signaling activities.

Summary: Conditional ablation of Lrp6 in dorsal neural folds causes spinal neural tube defects that can be rescued by genetic activation of β-catenin or maternal supplementation of Wnt signaling agonists.

Analysis of Diurnal Variations in Heart Rate: Potential Applications for Chronobiology and Cardiovascular Medicine

Circadian factors likely influence the occurrence, development, therapy, and prognosis of cardiovascular diseases (CVDs). To determine the association between the heart rate (HR) diurnal parameters and CVD risks, we designed an analytical strategy to detect diurnal rhythms of HR using longitudinal data collected by clinically used Holter monitors and wearable devices. By combining in-house developed algorithms with existing analytical tools, we obtained trough phase and nocturnal variation in HR for different purposes. The analytical strategy is robust and also sensitive enough to identify variations in HR rhythms influenced by multiple effectors such as jet lag, geological location and altitude, and age from total 211 volunteers. A total of 10,094 sets of 24-h Holter ECG data were analyzed by stepwise partial correlation to determine the critical points of HR trough phase and nocturnal variation. The following HR diurnal patterns correlate with high CVD risk: arrhythmic pattern, anti-phase pattern, rhythmic patterns with trough phase less than 0 (extremely advanced diurnal pattern) or more than 5 (extremely delayed diurnal pattern), and nocturnal variation less than 2.75 (extremely low) or more than 26 (extremely high). In addition, HR trough phases from wearable devices were nearly identical to those from 24-h Holter monitoring from 12 volunteers by linear correlation and Bland-Altman analysis. Our analytical system provides useful information to identify functional diurnal patterns and parameters by monitoring personalized, HR-based diurnal changes. These findings have important implications for understanding how a regular heart diurnal pattern benefits cardiac function and raising the possibility of non-pharmacological intervention against circadian related CVDs. With the rapid expansion of wearable devices, public cardiovascular health can be promoted if the analytical strategy is widely applied.

NACA and LRP6 Are Part of a Common Genetic Pathway Necessary for Full Anabolic Response to Intermittent PTH

PTH induces phosphorylation of the transcriptional coregulator NACA on serine 99 through Gαs and PKA. This leads to nuclear translocation of NACA and expression of the target gene Lrp6, encoding a coreceptor of the PTH receptor (PTH1R) necessary for full anabolic response to intermittent PTH (iPTH) treatment. We hypothesized that maintaining enough functional PTH1R/LRP6 coreceptor complexes at the plasma membrane through NACA-dependent Lrp6 transcription is important to ensure maximal response to iPTH. To test this model, we generated compound heterozygous mice in which one allele each of Naca and Lrp6 is inactivated in osteoblasts and osteocytes, using a knock-in strain with a Naca⁹⁹ Ser-to-Ala mutation and an Lrp6 floxed strain (test genotype: Naca^99S/A; Lrp6^+/fl;OCN-Cre). Four-month-old females were injected with vehicle or 100 μg/kg PTH(1-34) once daily, 5 days a week for 4 weeks. Control mice showed significant increases in vertebral trabecular bone mass and biomechanical properties that were abolished in compound heterozygotes. Lrp6 expression was reduced in compound heterozygotes vs. controls. The iPTH treatment increased Alpl and Col1a1 mRNA levels in the control but not in the test group. These results confirm that NACA and LRP6 form part of a common genetic pathway that is necessary for the full anabolic effect of iPTH.

[Application of endobronchial ultrasound in children: an analysis of 4 cases]

Objective: To investigate the feasibility, clinical efficacy and safety of endobronchial ultasound (EBUS) in children. Methods: The radiological features, EBUS images, pathological results and intraoperative and postoperative complications of 3 cases who underwent EBUS examination and 1 case who underwent EBUS guided transbronchial needle aspiration (EBUS-TBNA) were retrospectively analyzed. Results: Among the 4 cases, 2 were males and 2 were females, with the onset age of 7.4-9.2 years. The child who underwent successful EBUS-TBNA was presented with fever and diagnosed with mediastinal lymphadenopathy before the operation, and the postoperative pathology indicated histiocytic necrotic lymphadenitis (HNL). The other 3 children diagnosed with primary airway tumors, whose pre-operative CT imaging found no infiltration in extra-bronchial structures, had the masses resected through EBUS. According to postoperative pathological findings, two were diagnosed with mucoepidermoid carcinoma and one with bronchial leiomyoma. The lesions were located at the opening of the right main bronchus in 1 case and at the main airway in 2 cases. EBUS showed abnormal echogenicity of the tracheal wall in the 3 cases, including hyperechoic area in the water capsule and mucous layer, relatively hypoechoic area in the submucosal smooth muscle layer, hyperechoic area in the inner cartilage layer, hypoechoic in the cartilage layer and hyperechoic in the outer cartilage layer. In one case, structural disorder of the submucosal smooth muscle layer and partial disruption of the cartilage layer of the tracheal wall were found at the lesion site, while the other 2 cases had intact tracheal wall structure. There were no postoperative complications such as pneumothorax or hemoptysis in the 4 children. Conclusion: EBUS is a safe and feasible technique for evaluating mediastinal lymph node enlargement and the degree of airway wall infiltration in primary airway tumor.

Environmental mechanisms of orofacial clefts

Orofacial clefts (OFCs) are among the most common birth defects and impart a significant burden on afflicted individuals and their families. It is increasingly understood that many nonsyndromic OFCs are a consequence of extrinsic factors, genetic susceptibilities, and interactions of the two. Therefore, understanding the environmental mechanisms of OFCs is important in the prevention of future cases. This review examines the molecular mechanisms associated with environmental factors that either protect against or increase the risk of OFCs. We focus on essential metabolic pathways, environmental signaling mechanisms, detoxification pathways, behavioral risk factors, and biological hazards that may disrupt orofacial development.

Veno-venous extracorporeal membrane oxygenation successfully treated a case of severe pulmonary hemorrhage caused by leptospirosis

BACKGROUND

Pulmonary hemorrhage is an important complication of leptospirosis. Once acute respiratory distress syndrome (ARDS) occurs as a secondary condition, treatment is extremely difficult and the mortality rate is very high.

CASE PRESENTATION

The patient was a 49-year-old. He was admitted to the hospital because he had experienced a fever and cough for 4 days. Hemorrhage, respiratory failure, ARDS and other symptoms appeared soon after admission. Due to severe pulmonary hemorrhage secondary to ARDS, mechanical ventilation was performed through tracheal intubation. During intubation, the patient suffered cardiac arrest, and the patient's condition worsened. He was confirmed to have leptospirosis through second-generation sequencing of the alveolar lavage fluid. Finally, we successfully treated the patient with penicillin as an anti-infective medication and venous-venous extracorporeal membrane oxygenation (v-vECMO). To the best of our knowledge, this report is the first to describe the successful application of ECMO in mainland China.

CONCLUSIONS

Leptospirosis can induce serious but transient ARDS with a better prognosis than other causes of ARDS. Our patient was successfully treated with V-vECMO.

Role of epigenetics and miRNAs in orofacial clefts

Orofacial clefts (OFCs) have multiple etiologies and likely result from an interplay between genetic and environmental factors. Within the last decade, studies have implicated specific epigenetic modifications and noncoding RNAs as additional facets of OFC etiology. Altered gene expression through DNA methylation and histone modification offer novel insights into how specific genes contribute to distinct OFC subtypes. Epigenetics research has also provided further evidence that cleft lip only (CLO) is a cleft subtype with distinct etiology. Polymorphisms or misexpression of genes encoding microRNAs, as well as their targets, contribute to OFC risk. The ability to experimentally manipulate epigenetic changes and noncoding RNAs in animal models, such as zebrafish, Xenopus, mice, and rats, has offered novel insights into the mechanisms of various OFC subtypes. Although much remains to be understood, recent advancements in our understanding of OFC etiology may advise future strategies of research and preventive care.

Cellular and developmental basis of orofacial clefts

During craniofacial development, defective growth and fusion of the upper lip and/or palate can cause orofacial clefts (OFCs), which are among the most common structural birth defects in humans. The developmental basis of OFCs includes morphogenesis of the upper lip, primary palate, secondary palate, and other orofacial structures, each consisting of diverse cell types originating from all three germ layers: the ectoderm, mesoderm, and endoderm. Cranial neural crest cells and orofacial epithelial cells are two major cell types that interact with various cell lineages and play key roles in orofacial development. The cellular basis of OFCs involves defective execution in any one or several of the following processes: neural crest induction, epithelial-mesenchymal transition, migration, proliferation, differentiation, apoptosis, primary cilia formation and its signaling transduction, epithelial seam formation and disappearance, periderm formation and peeling, convergence and extrusion of palatal epithelial seam cells, cell adhesion, cytoskeleton dynamics, and extracellular matrix function. The latest cellular and developmental findings may provide a basis for better understanding of the underlying genetic, epigenetic, environmental, and molecular mechanisms of OFCs.

Genetics and signaling mechanisms of orofacial clefts

Craniofacial development involves several complex tissue movements including several fusion processes to form the frontonasal and maxillary structures, including the upper lip and palate. Each of these movements are controlled by many different factors that are tightly regulated by several integral morphogenetic signaling pathways. Subject to both genetic and environmental influences, interruption at nearly any stage can disrupt lip, nasal, or palate fusion and result in a cleft. Here, we discuss many of the genetic risk factors that may contribute to the presentation of orofacial clefts in patients, and several of the key signaling pathways and underlying cellular mechanisms that control lip and palate formation, as identified primarily through investigating equivalent processes in animal models, are examined.

[Comparison of long-term efficacy between watch and wait strategy and total mesorectal excision in locally advanced rectal cancer patients with clinical complete response after neoadjuvant therapy]

Objective: To compare long-term efficacy between watch and wait (W&W) strategy and total mesorectal excision (TME) in patients who were diagnosed with locally advanced rectal cancer (LARC) and attained clinical complete response (cCR) after neoadjuvant chemoradiotherapy (nCRT). Methods: A retrospective cohort study was carried out. A total of 238 patients with stage II-III LARC exhibiting cCR after nCRT in Sun Yat-sen University Cancer Center from September 16, 2010 to January 9, 2018 were enrolled. Patients who were diagnosed with other malignant tumor within 5 years, did not receive regular follow-up in our center for more than 1 year and had no complete examination items after nCRT were excluded. Of 238 patients, 151 were male and 87 were female with a median age of 57 (27-83) years old. According to TNM stage, 61 cases were cII, 177 cases were cIII. Concurrent chemoradiotherapy (CCRT) was performed in 20 patients. CCRT plus induction/consolidated chemotherapy was performed in 218 patients. Intensity-modulated radiotherapy (IMRT) was applied to radiotherapy. The median radiation dose was 50 Gy/25 Fr for both the primary tumor and clinical target volumes, and the total dose was 45.0 to 50.6 Gy for 227 patients. In 27 patients, single-agent fluorouracil or capecitabine was used as concurrent chemotherapy. But in the other 211 patients, a combined regimen of oxaliplatin and fluorouracil or capecitabine was used. After nCRT, 59 and 179 patients received W&W (W&W group) and TME 6-12 weeks later (TME group), respectively. After the ending of treatment, patient was interviewed one time every 3 months and after 3 years, one time every six months. Overall survival (OS) rate, distant-metastasis-free survival (DMFS) rate, and local-recurrence-free survival (LRFS) rate were compared between two groups. The salvage treatment and sphincter preservation rate were analyzed. The survival curve was drawn with Kaplan-Meier method and evaluated by log-rank method. Results: In the cases treated with TME, the median interval from nCRT to surgery was 59 days. The postoperative pCR rate was 63.1%(113/179). The median follow-up time of the whole cohort was 41.8 (12.0-99.0) months. The 3-year and 5-year OS rates were 98.4% and 96.5%; the 3-year and 5-year LRFS rates were 96.5% and 96.5%; the 3- and 5-year DMFS rates were 91.0% and 87.9%, respectively. The 3-year OS rates in the W&W group and the TME group were 100% and 97.9%; the 5-year OS rates in W&W group and the TME group were 90.6% and 97.9% (P=0.339); The 3-year local recurrence rate (LRR) in the W&W group was 12.9% (7 cases recurred within 2 years), which was significanthy higher then that in the TME group (0.6%, P=0.003). Salvage surgery was successful in 5/6 cases. After salvage surgery, LRFS rate was not significantly different between the two groups (P=0.137). The 3-year DMFS rate in the W&W group and the TME group were 88.4% and 81.1%, whose difference was not significant (P=0.593). Recurrence with simultaneous metastasis was seen in 3/7 cases of the W&W group. The sphincter was preserved in 89.8% (53/59) of patients in the W&W group, which was significantly higher than 73.7% (132/179) in the TME group (P<0.001). When distance of tumor from the anal verge was ≤ 5 cm, the sphincter preservation rate (SPR) in the W&W group was 88.0% (44/50), which was significantly higher than the 54.4% (56/103) in the TME group (P<0.001). Conclusions: W&W is safe and feasible for patients with LARC and cCR after nCRT. The results should be verified by further clinical trials.

[Effect of silencing FABP3 gene on LPS-induced apoptosis and endoplasmic reticulum stress in alveolar epithelial cells]

Objective: To investigate the effect of silencing fatty acid binding protein 3 (FABP3) gene on lipopolysaccharide (LPS)-induced apoptosis and endoplasmic reticulum stress in alveolar epithelial cells A549. Methods: According to the processing method, A549 cells were divided into control group(A549 cells cultured for 24 h), LPS group (10 mg/L LPS treated A549 cells for 24 h), LPS+si-con group (10 mg/L LPS was used to treat A549 cells transfected with si-con for 24 h) and LPS+si-FABP3 group (10 mg/L LPS was used to treat A549 cells transfected with si-FABP3 for 24 h). Then quantitative real-time PCR was used to detect the level of FABP3, methylthiazoletrazolium was used to detect the cell proliferation, flow cytometry was used to detect the apoptosis, and Western Blot was used to detect the levels of FABP3, CyclinD1, cleaved-caspase-3, GRP78, ATF4, CHOP, cleaved-caspase-12 and p-Akt and PI3Kp110α protein expression. Enzyme-linked immunosorbent assay was used to detect the levels of IL-6, IL-8 and TNF-αlevels. Results: In the LPS group, FABP3 protein level (1.00±0.09) and mRNA (2.15±0.22), apoptosis rate [(26.1±2.6)%], inflammatory factor IL-6 [(554.4±55.4) ng/L], IL-8 [(389.3±38.5) ng/L] and TNF-α [(601.3±60.0) ng/L], cleaved-caspase-3 (1.00±0.11), GRP78 (1.05±0.11), ATF4 (1.20±0.12)), CHOP (1.05±0.10), cleaved-caspase-12 (1.10±0.11), p-Akt (0.88±0.08) and PI3Kp110α (0.75±0.08) protein levels were significantly higher than the control group [(0.53±0.05), (1.00±0.10), (4.5±0.5)%, (75.4±7.5) ng/L, (25.2±2.5) ng/L, (66.5±6.7) ng/L, (0.34±0.05), (0.35±0.05), (0.43±0.05), (0.37±0.04), (0.45±0.05), (0.16±0.04), (0.35±0.05)] (all P<0.05). Cell viability [(50.1±5.4)%] and CyclinD1 protein level (0.40±0.05) in LPS group were significantly lower than those in the control group [(100.1±12.4)%, (1.25±0.12)] (both P<0.05). Cell viability [(89.1±8.5)%] and CyclinD1 protein level (1.15±0.11) in LPS+si-FABP3 group were significantly higher than those in LPS+si-con group [(53.1±5.4)%, (0.42±0.05)] (both P<0.05). Apoptosis rate [(10.5±1.1)%], IL-6[(301.3±30.0) ng/L], IL-8[(189.4±19.0) ng/L], TNF-α [(400.1±40.1) ng/L], cleaved-caspase-3 (0.45±0.05), GRP78 (0.48±0.05), ATF4 (0.60±0.06), CHOP (0.55±0.05), cleaved-caspase-12 (0.60±0.06), p-Akt (0.50±0.05) and PI3Kp110α(0.45±0.05) in LPS+si-FABP3 group were significantly lower than those in LPS+si-con group [(28.1±2.8)%, (536.3±53.6) ng/L, (400.2±40.2) ng/L, (623.1±62.3) ng/L, (0.96±0.10), (1.02±0.10), (1.15±0.12), (1.10±0.11), (1.15±0.12), (0.90±0.09), (0.72±0.07)] (all P<0.05). Conclusion: Silencing FABP3 gene can inhibit LPS-induced alveolar epithelial cell apoptosis and endoplasmic reticulum stress, which may act by inhibiting the PI3K/Akt signaling pathway.

Olig2 regulates terminal differentiation and maturation of peripheral olfactory sensory neurons

The bHLH transcription factor Olig2 is required for sequential cell fate determination of both motor neurons and oligodendrocytes and for progenitor proliferation in the central nervous system. However, the role of Olig2 in peripheral sensory neurogenesis remains unknown. We report that Olig2 is transiently expressed in the newly differentiated olfactory sensory neurons (OSNs) and is down-regulated in the mature OSNs in mice from early gestation to adulthood. Genetic fate mapping demonstrates that Olig2-expressing cells solely give rise to OSNs in the peripheral olfactory system. Olig2 depletion does not affect the proliferation of peripheral olfactory progenitors and the fate determination of OSNs, sustentacular cells, and the olfactory ensheathing cells. However, the terminal differentiation and maturation of OSNs are compromised in either Olig2 single or Olig1/Olig2 double knockout mice, associated with significantly diminished expression of multiple OSN maturation and odorant signaling genes, including Omp, Gnal, Adcy3, and Olfr15. We further demonstrate that Olig2 binds to the E-box in the Omp promoter region to regulate its expression. Taken together, our results reveal a distinctly novel function of Olig2 in the periphery nervous system to regulate the terminal differentiation and maturation of olfactory sensory neurons.

[Clinical characteristics of 46 pediatric diffuse large B-cell lymphoma and treatment outcome]

Objective: To summarize the clinical data of diffuse large B-cell lymphoma (DLBCL) in children and to evaluate the efficacy of Beijing Children's Hospital B cell lymphoma protocol in the treatment of pediatric DLBCL. Methods: The data (clinical, pathology, lab and image data) of 46 pediatric DLBCL admitted to the treatment group of Beijing Children's Hospital from January 2005 to June 2017 were collected and analyzed retrospectively. According to the risk factors of staging, existence of poor prognosis genes and giant tumors, stratified treatment was carried out according to the international standard modified LMB89 regimen with high dose and short course. The Kaplan-Meier method was used to calculate the event free survival (EFS) and the overall survival (OS). Results: (1) Among the 46 cases, there were 33 males and 13 females. The median age was 8.0 years. The time from the initial symptom onset to the diagnosis was more than 15 days in 45 children. Fourteen cases had B group symptoms (fever, night sweat, and weight lost), 25 cases had extranodal disease, 39 cases were stage Ⅲ and Ⅳ, 12 cases had bone marrow involvement, 3 cases had jawbone involvement. Thirty cases were group B and 16 cases were group C in the treatment group. (2) Initial symptoms: 6 cases had cervical mass, 20 cases had abdominal mass, 10 had abdominal pain with acute abdomen, 8 cases had fever, 2 cases had snore or upper respiratory tract obstruction. (3) Pathology result: 40 cases were germinal center B cell DLBCL, 6 cases were non germinal center B cell DLBCL, no case had the MYC gene rupture, double hit lymphoma and triple hit lymphoma. (4) Complication and evaluation: the tumor lysis syndrome was seen in 3 cases initially, severe infection and delayed treatment was seen in 1 case, no treatment related death. The first evaluation showed all cases were sensitive to chemotherapy (shrink>25%), the second evaluation showed 1 case had residual disease, the others were complete remission. (5) Treatment and outcome: the 5 year-EFS was the same with 5 year-OS, both were (97.8±2.2) %. Two cases relapsed after treatment off, early relapse was seen in 1 case, and died because of abandoning treatment. Late relapse was seen in 1 case and got a complete remission after Rituximab+group C protocol treatment. Conclusions: Pediatric DLBCL was common in school aged boys, most cases were at middle and late stage at the time of diagnosis. DLBCL had a good prognosis after the treatment with Beijing Children's Hospital's B cell lymphoma protocol, but late relapse could be seen.

[Clinical analysis of methylmalonic acidemia and hyperhomocysteinemia with diffuse lung disease as an initial or main presentation]

Objective: To improve the awareness of methylmalonic acidemia and hyperhomocysteinemia with diffuse lung disease as an initial or main presentation. Methods: A retrospective analysis of the clinical manifestations, radiological features, laboratory tests, genetic variations, treatments and prognoses was conducted in six children presented with diffuse lung disease and finally diagnosed with methylmalonic acidemia and hyperhomocysteinemia in Ward 2 of Department of Respiratory Diseases, Beijing Children's Hospital, from August 2017 to November 2018. Results: Six children were included in this study. Two children were male and four were female. The average age of onset was 28 months. The mean age at diagnosis was 34 months. The average interval from onset to diagnosis was 6 months. Four children who underwent genetic tests were found to have variants of gene MMACHC and diagnosed with CblC type. All children had respiratory symptoms and signs as initial or main presentation, which were tachypnea (5 cases), exercise intolerance (5 cases), cough (4 cases), cyanosis (4 cases), clubbing (4 cases), dyspnea (3 cases) and retractions (3 cases). Pulmonary arterial hypertension was found in all six children. Pericardial effusion (4 cases), kidney involvement (3 cases), nervous system involvement (3 cases), gastrointestinal system involvement (3 cases) and anemia (2 cases) also coexisted. The high resolution computed tomography (HRCT) features included dilated pulmonary artery (6 cases), ground-glass opacities (4 cases), diffuse poorly defined ground-glass centrilobular nodules (3 cases), pleural effusion (3 cases), thickening of interlobular septum (2 cases), etc. All children had an elevated concentration of methylmalonic acid in urine and homocysteine in plasma. Genetic tests were performed in four patients, and MMACHC genetic mutations were found in all of them. Clinical manifestations, HRCT features and pulmonary arterial hypertension turned better in five children after treatment. One patient who was not regularly followed-up died. Conclusions: Pulmonary involvement including diffuse lung disease and pulmonary arterial hypertension could coexist with methylmalonic acidemia and hyperhomocysteinemia, which may have respiratory symptoms and signs as the initial or main presentation. Characteristic HRCT features were found in some patients. Plasma homocysteine test is a quick method for screening the disease in children with diffuse lung disease and (or) pulmonary arterial hypertension. Both diffuse lung disease and pulmonary arterial hypertension may turn better after treatment.

Impaired neurodevelopmental pathways in autism spectrum disorder: a review of signaling mechanisms and crosstalk

Background

The development of an autistic brain is a highly complex process as evident from the involvement of various genetic and non-genetic factors in the etiology of the autism spectrum disorder (ASD). Despite being a multifactorial neurodevelopmental disorder, autistic patients display a few key characteristics, such as the impaired social interactions and elevated repetitive behaviors, suggesting the perturbation of specific neuronal circuits resulted from abnormal signaling pathways during brain development in ASD. A comprehensive review for autistic signaling mechanisms and interactions may provide a better understanding of ASD etiology and treatment.

Main body

Recent studies on genetic models and ASD patients with several different mutated genes revealed the dysregulation of several key signaling pathways, such as WNT, BMP, SHH, and retinoic acid (RA) signaling. Although no direct evidence of dysfunctional FGF or TGF-β signaling in ASD has been reported so far, a few examples of indirect evidence can be found. This review article summarizes how various genetic and non-genetic factors which have been reported contributing to ASD interact with WNT, BMP/TGF-β, SHH, FGF, and RA signaling pathways. The autism-associated gene ubiquitin-protein ligase E3A (UBE3A) has been reported to influence WNT, BMP, and RA signaling pathways, suggesting crosstalk between various signaling pathways during autistic brain development. Finally, the article comments on what further studies could be performed to gain deeper insights into the understanding of perturbed signaling pathways in the etiology of ASD.

Conclusion

The understanding of mechanisms behind various signaling pathways in the etiology of ASD may help to facilitate the identification of potential therapeutic targets and design of new treatment methods.

[Clinical and prognostic analysis of 186 children with Burkitt's lymphoma]

Objective: To analyze the clinical features and prognostic factors of childhood Burkitt's lymphoma and to summarize the therapeutic effect of the mature B-cell lymphoma regimen of Beijing Children's Hospital. Methods: It was a retrospective study. From January 2007 to December 2015, 186 patients below 18 years of age with newly diagnosed, untreated Burkitt's lymphoma were enrolled. Three cases were eliminated because of the abandonment of the treatment and 183 cases were stratified and treated according to the mature B-cell lymphoma regimen of Beijing Children's Hospital, groups were as follows: A, n=1; B, n=59; C, n=123 and 97 patients in group C received combined rituximab therapy during the treatment. The clinical features and therapeutic effects of patients were analyzed, overall survival (OS) and event-free survival (EFS) were estimated by the Kaplan-Meier method. COX regression was used to identify the prognostic factors. Results: The median age at diagnosis was 5 (1-14) years. There were 159 males (85.5%) and 27 females (14.5%) , the male-to-female ratio was 5.9∶1. A total of 174 cases (93.5%) evolved to stage Ⅲ and Ⅳ. Eight cases did not achieve remission and progressed to death, 9 cases relapsed. Only 5 patients (2.7%) died of treatment-related complications. With a median follow-up time of 48.0 (0.5-128.0) months, the 5-year OS rate and EFS rate were (89.1±2.3) % and (87.8±2.5) %. There was significant difference in the 5-year EFS rate between group B and C ( (94.9±2.9) % vs. (84.0±3.4) %, χ(2)=4.258, P=0.039). The 5-year EFS rate was (73.1±8.7) % and (86.7±3.7) % for patients in the group C treated with chemotherapy only and those treated with chemotherapy combined rituximab, but no statistical difference was found between them (χ(2)=3.360, P=0.067) . Central nervous system (CNS) involvement, insensitivity to early phase chemotherapy, residual diseases in mid-term evaluation were independent unfavorable prognostic factors (HR=6.167, 9.102, 3.104, 95%CI: 2.293-16.592, 1.837-45.107, 1.182-8.153) . Conclusions: The large dose, short course treatment of mature B-cell lymphoma regimen of Beijing Children's Hospital is effective for pediatric Burkitt's Lymphoma. Combined treatment with rituximab can improve the efficacy. CNS involvement, insensitivity to early phase chemotherapy, residual diseases in mid-term evaluation are associated with increased risk of poor prognosis.

Wnt signaling in orofacial clefts: crosstalk, pathogenesis and models

Diverse signaling cues and attendant proteins work together during organogenesis, including craniofacial development. Lip and palate formation starts as early as the fourth week of gestation in humans or embryonic day 9.5 in mice. Disruptions in these early events may cause serious consequences, such as orofacial clefts, mainly cleft lip and/or cleft palate. Morphogenetic Wnt signaling, along with other signaling pathways and transcription regulation mechanisms, plays crucial roles during embryonic development, yet the signaling mechanisms and interactions in lip and palate formation and fusion remain poorly understood. Various Wnt signaling and related genes have been associated with orofacial clefts. This Review discusses the role of Wnt signaling and its crosstalk with cell adhesion molecules, transcription factors, epigenetic regulators and other morphogenetic signaling pathways, including the Bmp, Fgf, Tgfβ, Shh and retinoic acid pathways, in orofacial clefts in humans and animal models, which may provide a better understanding of these disorders and could be applied towards prevention and treatments.

Supplementation with CTGF, SDF1, NGF, and HGF promotes ovine in vitro oocyte maturation and early embryo development

The strategies for improving the in vitro maturation (IVM) of domestic animal oocytes focus on promoting nuclear and cytoplasmic maturation. The identification of paracrine factors and their supplementation in the culture medium represent effective approaches for oocyte maturation and embryo development. This study investigated the effects of paracrine factor supplementation including connective tissue growth factor (CTGF), nerve growth factor (NGF), hepatocyte growth factor (HGF), and stromal derived factor 1 (SDF1) on ovine oocytes and early parthenogenetic embryos using an in vitro culture system. First, we identified the optimal concentrations of CTGF (30 ng/mL), SDF1 (10 ng/mL), NGF (3 ng/mL), and HGF (100 ng/mL) for promoting oocyte maturation, which combined, induced nuclear maturation in 94.19% of oocytes. This combination also promoted cumulus cell expansion and inhibited oocyte/cumulus apoptosis, while enabling a larger proportion (33.04%) of embryos to develop into blastocysts than in the controls and prevented embryo apoptosis. These novel findings demonstrate that the paracrine factors CTGF, SDF1, NGF, and HGF facilitate ovine oocyte and early parthenogenetic embryo development in vitro. Thus, supplementation with these factors may help optimize the IVM of ovine oocytes and early parthenogenetic embryo development strategies.

[Clinical features and diagnosis of childhood leukoencephalopathy with cerebral calcifications and cysts in four cases]

Objective: To investigate the clinical features and diagnostic bases of childhood leukoencephalopathy with cerebral calcifications and cysts (LCC). Methods: The clinical data involving manifestations and laboratory examinations of 4 children with LCC admitted to Beijing Children's Hospital Affiliated to Capital Medical University from 2012 to 2017 were retrospectively summarized. Each patient had a follow-up visit ranging from 4 months to 5 years and 9 months after initial examination. Results: Patients consisted of 2 males and 2 females, whose age of onset was respectively 2 years and 9 months, 6 years and 2 months, 7 years and 10 months, and 5 years and 1 month. The main clinical symptoms of these cases included headache, dizziness, partial seizure and claudication, and two of these cases had insidious onset. Cerebral calcifications and cysts with leukoencephalopathy were detected by neuroimaging in all patients. In addition, multifocal microhemorrhages and calcifications were observed by magnetic susceptibility-weighted imaging (SWI) series in 3 patients. Brain biopsy performed on 1 case disclosed a neuronal reduction in the cerebral cortex, loosening of focal white matter, multifocal lymphocyte infiltration, fresh hemorrhages, and gliosis, as well as angiomatous changes of blood vessels with hyalinized thicken-wall, stenotic or occlusive lumina and calcification deposits. The compound heterozygous mutations of n.*10G>A and n.82A>G in SNORD118 were identified in 1 case by target-capture next-generation sequencing. Sanger sequencing verified that the variant n.*10G>A was a novel mutation and it was of paternal-origin, while the variant n.82A>G was of maternal-origin, which had already been reported to be pathogenic to LCC. Follow-up study had shown continued partial seizure in 1 case and remissive claudication in another, while the remaining 2 cases had a relatively favorable outcome without obvious neurological symptoms at present time. Conclusions: The clinical manifestations of LCC are nonspecific, and the onset of the disease tends to be insidious. The triad neuroimaging findings of cerebral calcifications, cysts and leukoencephalopathy are essential to the diagnosis of the disease, and the signals of microhemorrhages revealed by SWI series provide another eloquent reference for the diagnosis. As biopsy is invasive and usually unavailable in the early stage, gene assessment, instead of pathological data, should be the gold standard in the diagnosis of LCC.

Wnt Signaling in Kidney Development and Disease

Wnt signal cascade is an evolutionarily conserved, developmental pathway that regulates embryogenesis, injury repair, and pathogenesis of human diseases. It is well established that Wnt ligands transmit their signal via canonical, β-catenin-dependent and noncanonical, β-catenin-independent mechanisms. Mounting evidence has revealed that Wnt signaling plays a key role in controlling early nephrogenesis and is implicated in the development of various kidney disorders. Dysregulations of Wnt expression cause a variety of developmental abnormalities and human diseases, such as congenital anomalies of the kidney and urinary tract, cystic kidney, and renal carcinoma. Multiple Wnt ligands, their receptors, and transcriptional targets are upregulated during nephron formation, which is crucial for mediating the reciprocal interaction between primordial tissues of ureteric bud and metanephric mesenchyme. Renal cysts are also associated with disrupted Wnt signaling. In addition, Wnt components are important players in renal tumorigenesis. Activation of Wnt/β-catenin is instrumental for tubular repair and regeneration after acute kidney injury. However, sustained activation of this signal cascade is linked to chronic kidney diseases and renal fibrosis in patients and experimental animal models. Mechanistically, Wnt signaling controls a diverse array of biologic processes, such as cell cycle progression, cell polarity and migration, cilia biology, and activation of renin-angiotensin system. In this chapter, we have reviewed recent findings that implicate Wnt signaling in kidney development and diseases. Targeting this signaling may hold promise for future treatment of kidney disorders in patients.

Celecoxib targets breast cancer stem cells by inhibiting the synthesis of prostaglandin E2 and down-regulating the Wnt pathway activity

Pharmacological targeting of breast cancer stem cells (CSCs) is highly promising for the treatment of breast cancer, as the small population of CSCs is responsible for tumor initiation, progression, recurrence and chemo-resistance. Celecoxib is one of the most commonly used non-steroidal anti-inflammatory drugs (NSAIDs), which have chemo-preventive activity against cancers, including breast cancer and colorectal cancer. However, the mechanisms by which NSAIDs exert its cancer prevention effects have yet been completely understood. In the present study, we investigated for the first time the effect of celecoxib on breast CSCs inhibition and its potential molecular mechanisms. Our results demonstrated that celecoxib suppresses CSC self-renewal, sensitizes chemo-resistance, inhibits epithelial to mesenchymal transition (EMT), and attenuates metastasis and tumorigenesis. Further exploring the underlying mechanism revealed that celecoxib targets breast CSCs by inhibiting the synthesis of prostaglandin E₂ and down-regulating the Wnt pathway activity. Our findings suggest that celecoxib, by targeting CSCs, may be used as an adjuvant chemotherapy drug to improve breast cancer treatment outcomes.

[Clinical pathologic characteristics and treatment outcomes of 19 relapsed pediatric B-cell lymphoma]

Objective: To review the clinical-pathology characteristics of 19 relapsed pediatric mature B cell lymphoma and to find the risk factors for recurrence and the feasible treatment after relapse. Method: Data of 212 pediatric B cell lymphomas cases in Beijing Children's Hospital from January 2006 to June 2015 were collected retrospectively. All the patients were treated according to the B cell lymphoma regimen of Beijing Children's Hospital. During the study period, 19 of 212 cases were relapsed; the clinio-pathological characteristics of relapsed patients before treatment and after relapse were analyzed retrospectively, the treatment outcomes after relapse were summarized and the patients were followed-up. Result: Nineteen of 212 cases had relapsed disease, for these relapsed patients: the median age at initial diagnosis was 5.5 years old, the median level of uric acid was 384(range, 121-713)μmol/L, the median level of lactate dehydrogenase(LDH) was 1 323(range, 146-6 370)U/L. Among 19 relapsed patients, 10 had local relapse and 9 had multiple relapses; 17 were Burkitt's lymphoma and 2 were diffuse large B cell lymphoma. Staging: 2 cases were stageⅡ, 3 cases were stage Ⅲ and 14 cases were stage Ⅳ. Risk group: 6 cases were group B and 13 cases were group C. Nine cases had bone marrow involvement and 10 cases had central nervous system(CNS) involvement. Acute tumor lysis syndrome was seen in 6 cases during the early treatment and 13 cases had delayed treatment. Treatment after relapse: 10 cases received further treatment after relapse (rituximab + 1-4 courses high intensity second-line chemotherapy), 3 cases received autologous stem cell transplantation. There was no chemotherapy or infection related death, 3 cases achieved complete remission (CR). For all the 212 patients, the median follow-up time was 47 (range, 1-131)months and the 5-year event free survival(EFS)rate was (89.4±0.2)%. For the 19 relapse cases, the 5-year overall survival (OS) rate was (21.1±0.1)%, CR rate after relapse was 30%, patients died of the progression of the primary disease, no treatment related death occurred. Univariate analyses showed that bulky disease, stage Ⅳ, maxillofacial and CNS involvement, LDH>1 000 U/L, delay treatment, day 7 evaluation shrink <25%, residual diseases after 3 months treatment are relapse risk factors (all P<0.01). Conclusion: Patients relapse during the treatment or at the early stage after the end of all chemotherapy have poor prognosis. So far there is no effective method for early relapse patients; the late relapse patients had the possibility of CR if they are sensitive to salvage treatment. In conclusion, to improve the outcome, the key point is to reduce the relapse.

[Abnormality of TOP2A expression and its gene copy number variations in neuroblastic tumors]

Objective: To detect TOP2A protein expression and gene copy number alterations, and to analyze related clinical and pathological implications in pediatric neuroblastic tumors (NT). Methods: Immunohistochemistry was used to detect TOP2A protein expression. Fluorescence in situ hybridization (FISH) was used to detect numerical aberrations of TOP2A. Results: TOP2A protein was expressed in 59.1%(52/88) of cases, which was associated with differentiation (P=0.006), Ki-67 index (P<0.01) and MKI (P=0.001). Twenty-eight cases (35.0%, 28/88) showed TOP2A gene amplification, which was correlated with the age (P<0.01), clinical stage (P=0.028), high risk group (P=0.001), Ki-67 index (P=0.040) and differentiation (P=0.014). Survival analysis showed that TOP2A expression was related to survival rate. Multivariate analyses showed that TOP2A expression was an independent predictor for poor prognosis (P=0.010). Conclusions: More than half of the cases show TOP2A expression, which is more likely associated with NB, high Ki-67 index and high MKI. Cases with TOP2A expression have shorter survivals and poorer prognosis. TOP2A amplification is seen in 35% and likely occurs in patients older than 18 months and at advanced INSS stages (Ⅲ and Ⅳ). As a target of the anthracycline-based adjuvant drugs, TOP2A test can be used to select patient with NT for the therapy.

[The clinical characteristics and outcomes of 16 Burkitt' s lymphoma with testicular involvement]

Objective: To analyze the clinical features and outcomes of Burkitt lymphoma with testicular involvement and study the efficiency of high dose methotrexate (HD-MTX: 5-8g/m2) in those patients without radiation therapy. Method: Retrospective analysis was conducted in 16 Burkitt's lymphoma cases with testicular lymphoma involvement between Jan 2009 and Dec 2014. We followed the BCH-NHL-2009 protocol, modified from FAB LMB 89 combined with rituximab. All patients were enrolled in high-risk group (treated by Group C protocol). Results: Of 137 Burkitt lymphoma, 16 (11.67% ) had testicular involvement. All the patients were in stage Ⅳ, the median age was 6.65 years (ranges: 2.25 to 13.5 years). 8 cases had bone marrow involvement, 9 with central nervous system involvement, 5 with bi-testicular involvement, 1 with EB virus infection (EBV-IgM+). The median follow-up was 31.8 months (ranges: 0.5 to 79 months). During the study period, 2 cases died, 1 due to the disease relapse, the other one due to chemo-related dead. 1 had disease relapse 32 months after off treatment; the other 13 cases were all event free survival. 3-year OS was 87.5%, 3-year EFS was 72.9%. We also found the level of testosterone in ten adolescent were normal before and after chemotherapy. Conclusion: For the Burkitt lymphoma with testicular involvement, we abandon radiotherapy, and administer HD-MTX to lower the toxicity. The short-term survival is better, long-term survival still needs to be clarified.

Multiple sequence alignment based on combining genetic algorithm with chaotic sequences

In bioinformatics, sequence alignment is one of the most common problems. Multiple sequence alignment is an NP (nondeterministic polynomial time) problem, which requires further study and exploration. The chaos optimization algorithm is a type of chaos theory, and a procedure for combining the genetic algorithm (GA), which uses ergodicity, and inherent randomness of chaotic iteration. It is an efficient method to solve the basic premature phenomenon of the GA. Applying the Logistic map to the GA and using chaotic sequences to carry out the chaotic perturbation can improve the convergence of the basic GA. In addition, the random tournament selection and optimal preservation strategy are used in the GA. Experimental evidence indicates good results for this process.

[Clinical analysis of two cases with diffuse pulmonary lymphatic disease]

OBJECTIVE

To analyze the clinical characteristics and diagnosis of 2 cases with diffuse pulmonary lymphatic disease.

METHOD

Clinical manifestations of the children were retrospectively analyzed. Two patients were both from Beijing Children Hospital in 2013 and 2014.Diffuse pulmonary lymphatic disease was diagnosed by pathology of pleura in case 1 and by lymphoscintigraphy in case 2.

RESULT

The first patient was a male aged 10-year-5-month who presented with a history of pleural effusion for 2 years. Examination revealed chylothorax and pericardial effusion. After pleural decortications and ligation of thoracic duct was performed, he still had recurrent chylothorax. Pathology of pleura revealed lymphangioma. Physical examination showed diminished breath sound and heart sounds. A bronchoscope revealed too much white viscous secretions. Thorax ultrasound revealed lymphangioma in bilateral lower thoracic cavity and post inferior mediastinum. Chest computed tomography showed diffuse thickening of the interlobular septa and bronchovascular bundle in both lungs, many punctate calcification in the lower field. Abdomen ultrasound revealed a small quantity seroperitoneum. Lymphoscintigraphy revealed radioactivity enhancement in bilateral thoracic cavity. The second patient was a female aged 6 years and 9 months, who presented with a history of recurrent cough for 2 years and 9 months. Physical examination showed normal result. Pulmonary function showed mixed ventilation function disturbance. A bronchoscopy showed extensive viscous secretions. Mediastinum, heart and abdomen were normal on ultrasound. Chest computed tomography showed diffuse thickening of the interlobular septa and bronchovascular bundle in both lungs and bilateral pleural thickening. Lymphoscintigraphy revealed diffuse lymphangiectasis in both lungs. Both patients received a diagnosis of diffuse pulmonary lymphatic disease. Case 1 who had died was diagnosed with diffuse pulmonary lymphangiomatosis. Case 2 had no exacerbation after 9 months' treatment with prednisone.

CONCLUSION

Diffuse pulmonary lymphatic disease might present with cough and shortness of breath and result in diffuse interstitial disease with thickening of the interlobular septa, refractory chylothorax, multiple lymphangioma in mediastinum, pericardial effusion and seroperitoneum. It could be diagnosed by pleura or lung tissue pathology and lymphoscintigraphy.

Novel polymorphic microsatellite markers for Bellamya and their application in population genetics of three species

Bellamya is a widely distributed freshwater snail genus in China; however, its genetic diversity is completely unknown. Sixty-five novel microsatellite loci were isolated and characterized from a microsatellite-enriched library of Bellamya aeruginosa genomic DNA. Most of the 65 loci were successfully amplified. We found high polymorphic information content values for these loci, ranging from 0.235 to 0.892. There were 3 to 12 alleles per locus, and the HE and HO varied from 0.425 to 0.953 and 0.026 to 1.000, respectively. Fifteen loci deviated significantly from Hardy-Weinberg equilibrium after Bonferroni's correction. All 65 SSR markers were tested in an additional five Bellamya species, and 96.9% of the 325 locus/taxon combinations tested resulted in cross-species amplification. Seven polymorphic microsatellite markers were randomly selected for comparison among nine populations of three species. All populations had moderate to high genetic diversity. In genetic distance-based cluster analysis, the populations of B. aeruginosa and B. dispiralis formed species-based clusters, whereas populations of B. angularia did not. The three examined Bellamya species could be differentiated using SSR markers. These microsatellite loci should be useful for genetic diversity analysis, analysis of phylogenetic relationship, and species delimitation of Bellamya.

LDL Receptor-Related Protein 6 Modulates Ret Proto-Oncogene Signaling in Renal Development and Cystic Dysplasia

Hypoplastic and/or cystic kidneys have been found in both LDL receptor-related protein 6 (Lrp6)- and β-catenin-mutant mouse embryos, and these proteins are key molecules for Wnt signaling. However, the underlying mechanisms of Lrp6/β-catenin signaling in renal development and cystic formation remain poorly understood. In this study, we found evidence that diminished cell proliferation and increased apoptosis occur before cystic dysplasia in the renal primordia of Lrp6-deficient mouse embryos. The expression of Ret proto-oncogene (Ret), a critical receptor for the growth factor glial cell line-derived neurotrophic factor (GDNF), which is required for early nephrogenesis, was dramatically diminished in the mutant renal primordia. The activities of other representative nephrogenic genes, including Lim1, Pax2, Pax8, GDNF, and Wnt11, were subsequently diminished in the mutant renal primordia. Molecular biology experiments demonstrated that Ret is a novel transcriptional target of Wnt/β-catenin signaling. Wnt agonist lithium promoted Ret expression in vitro and in vivo. Furthermore, Lrp6-knockdown or lithium treatment in vitro led to downregulation or upregulation, respectively, of the phosphorylated mitogen-activated protein kinases 1 and 3, which act downstream of GDNF/Ret signaling. Mice with single and double mutations of Lrp6 and Ret were perinatal lethal and demonstrated gene dosage-dependent effects on the severity of renal hypoplasia during embryogenesis. Taken together, these results suggest that Lrp6-mediated Wnt/β-catenin signaling modulates or interacts with a signaling network consisting of Ret cascades and related nephrogenic factors for renal development, and the disruption of these genes or signaling activities may cause a spectrum of hypoplastic and cystic kidney disorders.

Pax6 mediates ß-catenin signaling for self-renewal and neurogenesis by neocortical radial glial stem cells

The Wnt/ß-catenin pathway is a critical stem cell regulator and plays important roles in neuroepithelial cells during early gestation. However, the role of Wnt/ß-catenin signaling in radial glia, a major neural stem cell population expanded by midgestation, remains poorly understood. This study shows that genetic ablation of ß-catenin with hGFAP-Cre mice inhibits neocortical formation by disrupting radial glial development. Reduced radial glia and intermediate progenitors are found in the ß-catenin-deficient neocortex during late gestation. Increased apoptosis and divergent localization of radial glia in the subventricular zone are also observed in the mutant neocortex. In vivo and in vitro proliferation and neurogenesis as well as oligodendrogenesis by cortical radial glia or by dissociated neural stem cells are significantly defective in the mutants. Neocortical layer patterning is not apparently altered, while astrogliogenesis is ectopically increased in the mutants. At the molecular level, the expression of the transcription factor Pax6 is dramatically diminished in the cortical radial glia and the sphere-forming neural stem cells of ß-catenin-deficient mutants. Chromatin immunoprecipitation and luciferase assays demonstrate that ß-catenin/Tcf complex binds to Pax6 promoter and induces its transcriptional activities. The forced expression of Pax6 through lentiviral transduction partially rescues the defective proliferation and neurogenesis by ß-catenin-deficient neural stem cells. Thus, Pax6 is a novel downstream target of the Wnt/ß-catenin pathway, and ß-catenin/Pax6 signaling plays critical roles in self-renewal and neurogenesis of radial glia/neural stem cells during neocortical development.

Signaling mechanisms controlling cranial placode neurogenesis and delamination

The neurogenic cranial placodes are a unique transient epithelial niche of neural progenitor cells that give rise to multiple derivatives of the peripheral nervous system, particularly, the sensory neurons. Placode neurogenesis occurs throughout an extended period of time with epithelial cells continually recruited as neural progenitor cells. Sensory neuron development in the trigeminal, epibranchial, otic, and olfactory placodes coincides with detachment of these neuroblasts from the encompassing epithelial sheet, leading to delamination and ingression into the mesenchyme where they continue to differentiate as neurons. Multiple signaling pathways are known to direct placodal development. This review defines the signaling pathways working at the finite spatiotemporal period when neuronal selection within the placodes occurs, and neuroblasts concomitantly delaminate from the epithelium. Examining neurogenesis and delamination after initial placodal patterning and specification has revealed a common trend throughout the neurogenic placodes, which suggests that both activated FGF and attenuated Notch signaling activities are required for neurogenesis and changes in epithelial cell adhesion leading to delamination. We also address the varying roles of other pathways such as the Wnt and BMP signaling families during sensory neurogenesis and neuroblast delamination in the differing placodes.

β-catenin regulates Pax3 and Cdx2 for caudal neural tube closure and elongation

Non-canonical Wnt/planar cell polarity (PCP) signaling plays a primary role in the convergent extension that drives neural tube closure and body axis elongation. PCP signaling gene mutations cause severe neural tube defects (NTDs). However, the role of canonical Wnt/β-catenin signaling in neural tube closure and NTDs remains poorly understood. This study shows that conditional gene targeting of β-catenin in the dorsal neural folds of mouse embryos represses the expression of the homeobox-containing genes Pax3 and Cdx2 at the dorsal posterior neuropore (PNP), and subsequently diminishes the expression of the Wnt/β-catenin signaling target genes T, Tbx6 and Fgf8 at the tail bud, leading to spina bifida aperta, caudal axis bending and tail truncation. We demonstrate that Pax3 and Cdx2 are novel downstream targets of Wnt/β-catenin signaling. Transgenic activation of Pax3 cDNA can rescue the closure defect in the β-catenin mutants, suggesting that Pax3 is a key downstream effector of β-catenin signaling in the PNP closure process. Cdx2 is known to be crucial in posterior axis elongation and in neural tube closure. We found that Cdx2 expression is also repressed in the dorsal PNPs of Pax3-null embryos. However, the ectopically activated Pax3 in the β-catenin mutants cannot restore Cdx2 mRNA in the dorsal PNP, suggesting that the presence of both β-catenin and Pax3 is required for regional Cdx2 expression. Thus, β-catenin signaling is required for caudal neural tube closure and elongation, acting through the transcriptional regulation of key target genes in the PNP.

Concise review: Quiescent and active states of endogenous adult neural stem cells: identification and characterization

The adult mammalian central nervous system (CNS) lacks the capacity for regeneration, making it a highly sought-after topic for researchers. The identification of neural stem cells (NSCs) in the adult CNS wiped out a long-held dogma that the adult brain contains a set number of neurons and is incapable of replacing them. The discovery of adult NSCs (aNSCs) stoked the fire for researchers who dream of brain self-repair. Unfortunately, the quiescent nature and limited plasticity of aNSCs diminish their regenerative potential. Recent studies evaluating aNSC plasticity under pathological conditions indicate that a switch from quiescent to active aNSCs in neurogenic regions plays an important role in both repairing the damaged tissue and preserving progenitor pools. Here, we summarize the most recent findings and present questions about characterizing the active and quiescent aNSCs in major neurogenic regions, and factors for maintaining their active and quiescent states, hoping to outline an emerging view for promoting the endogenous aNSC-based regeneration.

Canonical Wnt signaling promotes the proliferation and neurogenesis of peripheral olfactory stem cells during postnatal development and adult regeneration

The mammalian olfactory epithelium (OE) has a unique stem cell or progenitor niche, which is responsible for the constant peripheral neurogenesis throughout the lifespan of the animal. However, neither the signals that regulate the behavior of these cells nor the lineage properties of the OE stem cells are well understood. Multiple Wnt signaling components exhibit dynamic expression patterns in the developing OE. We generated Wnt signaling reporter TOPeGFP transgenic mice and found TOPeGFP activation predominantly in proliferating Sox2(+) OE basal cells during early postnatal development. FACS-isolated TOPeGFP(+) OE basal cells are required, but are not sufficient, for formation of spheres. Wnt3a significantly promotes the proliferation of the Sox2(+) OE sphere cells. Wnt-stimulated OE sphere cells maintain their multipotency and can differentiate into most types of neuronal and non-neuronal epithelial cells. Also, Wnt activators shift the production of differentiated cells toward olfactory sensory neurons. Moreover, TOPeGFP(+) cells are robustly increased in the adult OE after injury. In vivo administration of Wnt modulators significantly alters the regeneration potential. This study demonstrates the role of the canonical Wnt signaling pathway in the regulation of OE stem cells or progenitors during development and regeneration.

The canonical Wnt/β-catenin signaling pathway regulates Fgf signaling for early facial development

The canonical Wnt/β-catenin signaling pathway has implications in early facial development; yet, its function and signaling mechanism remain poorly understood. We report here that the frontonasal and upper jaw primordia cannot be formed after conditional ablation of β-catenin with Foxg1-Cre mice in the facial ectoderm and the adjacent telencephalic neuroepithelium. Gene expression of several cell-survival and patterning factors, including Fgf8, Fgf3, and Fgf17, is dramatically diminished in the anterior neural ridge (ANR, a rostral signaling center) and/or the adjacent frontonasal ectoderm of the β-catenin conditional mutant mice. In addition, Shh expression is diminished in the ventral telencephalon of the mutants, while Tcfap2a expression is less affected in the facial primordia. Apoptosis occurs robustly in the rostral head tissues following inactivation of Fgf signaling in the conditional mutants. Consequently, the upper jaw, nasal, ocular and telencephalic structures are absent, but the tongue and mandible are relatively developed in the conditional mutants at birth. Using molecular biological approaches, we demonstrate that the Fgf8 gene is transcriptionally targeted by Wnt/β-catenin signaling during early facial and forebrain development. Furthermore, we show that conditional gain-of-function of β-catenin signaling causes drastic upregulation of Fgf8 mRNA in the ANR and the entire facial ectoderm, which also arrests facial and forebrain development. Taken together, our results suggest that canonical Wnt/β-catenin signaling is required for early development of the mammalian face and related head structures, which mainly or partly acts through the initiation and modulation of balanced Fgf signaling activity.

Cardiac neural crest and outflow tract defects in Lrp6 mutant mice

The role of a key Wnt coreceptor Lrp6 during heart development remains unclear. Here we show that ablation of Lrp6 in mice causes conotruncal anomalies including double-outlet right ventricle (DORV), outflow tract (OFT) cushion hypoplasia, and ventricular septal defect (VSD). Cardiac neural crest cells are specifically lost in the dorsal neural tube and caudal pharyngeal arches of the mutant embryos. We also demonstrate that Lrp6 is required for proliferation and survival of cardiac progenitors and for the expression of Isl1 in the secondary heart field. Other known cardiogenic regulators such as Msx1, Msx2, and Fgf8 are also significantly diminished in the mutant pharyngeal arches and/or OFT. Unexpectedly, the myocardium differentiation factors Mef2c and Myocardin are upregulated in the mutant OFT. Our results indicate that Lrp6 is essential for cardiac neural crest and OFT development upstream of multiple important cardiogenic genes in different cardiac lineage cells during early cardiogenesis.

Generation of Lrp6 conditional gene-targeting mouse line for modeling and dissecting multiple birth defects/congenital anomalies

Lrp6 is a key coreceptor in the canonical Wnt pathway that is widely involved in tissue/organ morphogenesis. We generated a loxP-floxed Lrp6 mouse line. Crossing with a general Cre deleter, we obtained the Lrp6-floxdel mice, in which the loxP-floxed exon 2 of Lrp6 gene has been deleted ubiquitously. The homozygotes of Lrp6-floxdel mice reproduced typical defects as seen in the conventional Lrp6-deficient mice, such as defects in eye, limb, and neural tube, and die around birth. We also found new phenotypes including cleft palate and agenesis of external genitalia in the Lrp6-floxdel mice. In addition, the Lrp6-deficient embryos are known to be defective in other systems and internal organs including the heart and brain. Thus, by selectively crossing with a lineage-specific or inducible Cre mouse line, the Lrp6 conditional gene-targeting mice will allow us to model specific types of birth defects for mechanism and prevention studies.