Single-cell landscape of the cellular microenvironment in three different colonic polyp subtypes in children.

BACKGROUND: The understanding of the heterogeneous cellular microenvironment of colonic polyps in paediatric patients with solitary juvenile polyps (SJPs), polyposis syndrome (PJS) and Peutz-Jeghers syndrome (PJS) remains limited. METHODS: We conducted single-cell RNA sequencing and multiplexed immunohistochemistry (mIHC) analyses on both normal colonic tissue and different types of colonic polyps obtained from paediatric patients. RESULTS: We identified both shared and disease-specific cell subsets and expression patterns that played important roles in shaping the unique cellular microenvironments observed in each polyp subtype. As such, increased myeloid, endothelial and epithelial cells were the most prominent features of SJP, JPS and PJS polyps, respectively. Noticeably, memory B cells were increased, and a cluster of epithelial-mesenchymal transition (EMT)-like colonocytes existed across all polyp subtypes. Abundant neutrophil infiltration was observed in SJP polyps, while CX3CR1hi CD8+ T cells and regulatory T cells (Tregs) were predominant in SJP and JPS polyps, while GZMAhi natural killer T cells were predominant in PJS polyps. Compared with normal colonic tissues, myeloid cells exhibited specific induction of genes involved in chemotaxis and interferon-related pathways in SJP polyps, whereas fibroblasts in JPS polyps had upregulation of myofiber-associated genes and epithelial cells in PJS polyps exhibited induction of a series of nutrient absorption-related genes. In addition, the TNF-α response was uniformly upregulated in most cell subsets across all polyp subtypes, while endothelial cells and fibroblasts separately showed upregulated cell adhesion and EMT signalling in SJP and JPS polyps. Cell-cell interaction network analysis showed markedly enhanced intercellular communication, such as TNF, VEGF, CXCL and collagen signalling networks, among most cell subsets in polyps, especially SJP and JPS polyps. CONCLUSION: These findings strengthen our understanding of the heterogeneous cellular microenvironment of polyp subtypes and identify potential therapeutic approaches to reduce the recurrence of polyps in children.

Circ_0001666 upregulation promotes intestinal epithelial cell fibrosis in pediatric Crohn's disease via the SRSF1/BMP7 axis.

The epithelial-mesenchymal transition (EMT) is closely associated with Crohn's disease (CD) related intestinal fibrosis, a condition whose prevalence is increasing annually among children. Recently, the CD marker gene microarray screening revealed an upregulation of circ_0001666 in the colon tissues of CD patients, but its underlying mechanisms remain unclear. In this study, we explored the molecular mechanism of circ_0001666 in regulating EMT-mediated fibrosis in CD in vitro. The levels of circ_0001666 and EMT-associated proteins were assessed in CD clinical samples, and a CD cell model was established using TGF-ß1 to induce human intestinal epithelial cells (HIECs). Additionally, the expression levels of genes and proteins related to EMT and fibrosis were analyzed by quantitative real-time PCR and western blot, cell migration, and invasion were assessed via wound healing assay and transwell, respectively, and RNA pull-down and RNA immunoprecipitation assays were performed to verify the relationship between SRSF1 and BMP7 or circ_0001666. Circ_0001666 was overexpressed in the intestinal mucosal tissues of CD patients and was positively correlated with EMT. Silencing circ_0001666 inhibited the migration, invasion, EMT, and fibrosis of HIECs induced by TGF-ß1. Mechanistically, circ_0001666 regulated BMP7 expression by interacting with SRSF1. Furthermore, the effects of inhibiting circ_0001666 on HIECs could be partially reversed by overexpressing SRSF1 or silencing BMP7. Collectively, circ_0001666 regulates TGF-ß1-induced HIEC migration, invasion, EMT, and fibrosis. Circ_0001666 also promoted EMT-mediated fibrosis by interacting with SRSF1 to accelerate BMP7 mRNA decay. These findings provide new insights into the pathogenesis of CD and suggest that circ_0001666 might be a potential therapeutic target for CD.

Expanding the mutational spectrum of ZTTK syndrome: A de novo variant with global developmental delay and malnutrition in a Chinese patient.

BACKGROUND: Zhu-Tokita-Takenouchi-Kim (ZTTK, OMIM 617140) syndrome is a severe multisystem developmental disorder characterized by intellectual disability, developmental delay, cortical malformations, epilepsy, visual problems, musculoskeletal abnormalities, and congenital malformations. ZTTK syndrome is caused by a heterozygous pathogenic variant of the SON gene (NM_138927) at chromosome 21q22.1. The purpose of this study was to investigate the pathogenesis of a 6-month-old Chinese child who exhibited global developmental delay, muscle weakness, malnutrition, weight loss, and strabismus, brain abnormality, immunological system abnormalities. METHODS: The little girl was tested for medical exome sequencing (MES) and mtDNA sequencing in trio. And, the mutation was validated by Sanger sequencing. RESULTS: A novel de novo frameshift variant, c.1845_1870del26 (p.G616Sfs*61), in the SON gene was found in the proband. CONCLUSION: We described a 6-month-old Chinese child with global developmental delay caused by pathogenic de novo mutation c.1845_1870del26 (p.G616Sfs*61) in the SON. Apart from a founder mutation, we reviewed the phenotypic abnormalities and genotypes in 79 individuals. The data showed that global developmental delay is accompanied by other system disorders. Our findings expanded the mutational spectrum of ZTTK syndrome and provide genetic counseling of baby with global developmental delay.

A "push-and-pull" trick for endoscopic removal of buckyballs impacted in the esophagus and gastric fundus.

As a common foreign body in children, magnet ingestion has been a widespread health issue. Unlike single magnet, ingestion of multiple magnets, especially those high-powered like Buckyballs could cause significant GI injury, e.g., perforation and fistula. Hereby we present a "push-and-pull" trick for management of a rare circumstance of Buckyballs ingestion.

[Clinical features of intestinal polyps and risk factors for secondary intussusception in children: an analysis of 2 669 cases]. / 2 669ä¾‹å„¿ç«¥è‚ æ¯è‚‰çš„ä¸´åºŠç‰¹å¾åŠç»§å‘è‚ å¥—å çš„å±é™©å› ç´ åˆ†æž.

OBJECTIVES: To study the clinical features of intestinal polyps and the risk factors for secondary intussusception in children. METHODS: A retrospective analysis was performed for the medical data of 2 669 children with intestinal polyps. According to the presence or absence of secondary intussusception, they were divided into two groups: intussusception (n=346) and non-intussusception (n=2 323). Related medical data were compared between the two groups. The multivariate logistic regression analysis was used to identify the risk factors for secondary intussusception. RESULTS: Among the children with intestinal polyps, 62.42% were preschool children, and the male/female ratio was 2.08∶1; 92.66% had hematochezia as disease onset, and 94.34% had left colonic polyps and rectal polyps. There were 346 cases of secondary intussusception, with an incidence rate of 12.96% (346/2 669). Large polyps (OR=1.644, P<0.001), multiple polyps (≥2) (OR=6.034, P<0.001), and lobulated polyps (OR=93.801, P<0.001) were the risk factors for secondary intussusception. CONCLUSIONS: Intestinal polyps in children often occur in preschool age, mostly in boys, and most of the children have hematochezia as disease onset, with the predilection sites of the left colon and the rectum. Larger polyps, multiple polyps, and lobulated polyps may increase the risk of secondary intussusception, and endoscopic intervention is needed as early as possible to improve prognosis.

[Effect of glutamine-supplemented enteral nutrition on the apoptosis of colonic mucosal cells in young rats with inflammatory bowl disease].

OBJECTIVE: To study the effect of glutamine-supplemented enteral nutrition in regulating the apoptosis of intestinal mucosal cells and promoting mucosal healing in young rats with inflammatory bowl disease (IBD). METHODS: A total of 80 male Sprague-Dawley rats aged 4-5 weeks were randomly divided into 4 groups: blank control, IBD model, short peptide, and short peptide+glutamine (n=20 each). The IBD model was prepared by a single colon perfusion of 3-nitrobenzene sulfonic acid. At 3 days after modeling, the rats in the short peptide group were fed with short peptide formula (100 mL/kg), and those in the short peptide+glutamine group were fed with short peptide formula (100 mL/kg) and glutamine (0.5 g/kg). The course of intervention was 1 week. General conditions were observed after the experiment and their intestinal mucosal tissue was obtained. Hematoxylin-eosin staining was used to observe the pathological change of the intestinal mucosa. RT-PCR was used to measure the expression of apoptosis-regulating genes (bax and bc1-2) and apoptotic signal transduction factors (Caspase-3 and Caspase-9) in the intestinal mucosa. Western blot was used to measure the expression of insulin-like growth factor-1 (IGF-1) in the colonic mucosa. RESULTS: The IBD model group had poorer general conditions than the other three groups (blank control, short peptide and short peptide+glutamine), and the short peptide+glutamine group had better general conditions than the IBD model and short peptide groups. The IBD model group had significantly higher mRNA expression of bax than the other three groups (P<0.05). There was no significant difference in the mRNA expression of bcl-2, Caspase-3 and Caspase-9 among the 4 groups (P>0.05). The short peptide group had a significantly higher level of IGF-1 than the short peptide+glutamine, blank control and IBD model groups (P<0.05). CONCLUSIONS: Glutamine-supplemented enteral nutrition can effectively improve the general nutritional status of young rats with IBD, but it is not better than exclusive enteral nutrition in inhibiting the apoptosis of colonic mucosal cells and stimulating the synthesis of IGF-1 in the intestinal mucosa.

Clinical and Genetic Study of Children With Peutz-Jeghers Syndrome Identifies a High Frequency of STK11 De Novo Mutation.

OBJECTIVES: The present study aims to identify the genotype-phenotype correlation in children with Peutz-Jeghers Syndrome (PJS) through the analysis of STK11 gene mutations in the context of clinical and pathological characteristics. METHOD: In this observational cohort study, the clinical characteristics of 18 families diagnosed with pediatric PJS were collected. Genomic DNA from the peripheral blood of affected children and their family members was collected. The coding region of STK11 was amplified by PCR and screened for mutation by Sanger sequencing. The families that were negative for STK11 mutation were further assessed by multiplex ligation-dependent probe amplification (MLPA). RESULT: Initial presentation in affected children was at 1.6 to 14.2 years and included anemia in 8 patients whereas 6 presented for screening by virtue of family history. All patients underwent endoscopy, colonoscopy, and polypectomy. Polyps were distributed throughout the gastrointestinal (GI) tract, including the small intestine, stomach, colon, and rectum.In the 18 pediatric PJS families, STK11 mutations were detected in 8 families by Sanger sequencing, and large deletions were detected in 3 by MLPA, respectively. Nine of the 11 STK11 mutations were de novo, 3 were novel (c.419T>C:p.L140P, c.314T>G:p.L105X), and (c.488_489insACGG p.L164fs). CONCLUSIONS: Although the main clinical features of pediatric PJS were similar to those of PJS cases in adults, a high frequency of STK11 de novo mutations were encountered in our population of patients with PJS.

Helicobacter pylori infection promotes the invasion and metastasis of gastric cancer through increasing the expression of matrix metalloproteinase-1 and matrix metalloproteinase-10.

The aim of this study was to investigate the effect and mechanism of Helicobacter pylori infection in the invasion and metastasis of gastric cancer. Specimens from 80 patients with gastric cancer (of which 20 patients had metastatic gastric cancer) and 40 patients with chronic gastritis were included in this study. H. pylori infection was determined by ELISA and the expression of matrix metalloproteinase-1 (MMP-1) and MMP-10 was observed using immunohistochemistry. The correlation between H. pylori infection and the clinical pathological features of gastric cancer was analyzed by SPSS 13.0 software. The protein expression levels of MMP-1 and MMP-10 in MGC-803 cells infected with H. pylori were analyzed using western blotting. H. pylori infection was found in 62 of the 80 patients with gastric cancer and in 13 of the 40 patients with chronic gastritis. In addition, H. pylori infection was correlated with the staging and lymph node metastasis, but not with the gender, age and histological types of patients. H. pylori infection was also significantly correlated with the expression of MMP-1 and MMP-10 (r=0.8718, P<0.05 and r=0.5477, P<0.05, respectively). The expression of MMP-1 and MMP-10 was significantly upregulated following induction by H. pylori infection (P<0.05), with significant effects occurring following infection for 12 and 6 h, respectively. H. pylori infection may promote the invasion and metastasis of gastric cancer by increasing the expression of MMP-1 and MMP-10.