TGFß1 single-nucleotide polymorphism C-509T alters mucosal cell function in pediatric eosinophilic esophagitis.

Eosinophilic esophagitis (EoE) is a chronic Th2 antigen-driven disorder associated with tissue remodeling. Inflammation and remodeling lead to esophageal rigidity, strictures, and dysphagia. TGFß1 drives esophageal remodeling including epithelial barrier dysfunction and subepithelial fibrosis. A functional SNP in the TGFß1 gene that increases its transcription (C-509T) is associated with elevated numbers of esophageal TGFß1-expressing cells. We utilized esophageal biopsies and fibroblasts from TT-genotype EoE children to understand if TGFß1 influenced fibroblast and epithelial cell function in vivo. Genotype TT EoE esophageal fibroblasts had higher baseline TGFß1, collagen1α1, periostin, and MMP2 (p < 0.05) gene expression and distinct contractile properties compared with CC genotype (n = 6 subjects per genotype). In vitro TGFß1 exposure caused greater induction of target gene expression in genotype CC fibroblasts (p < 0.05). Esophageal biopsies from TT-genotype subjects had significantly less epithelial membrane-bound E-cadherin (p < 0.01) and wider cluster distribution at nanometer resolution. TGFß1 treatment of stratified primary human esophageal epithelial cells and spheroids disrupted transepithelial resistance (p < 0.001) and E-cadherin localization (p < 0.0001). A TGFß1-receptor-I inhibitor improved TGFß1-mediated E-cadherin mislocalization. These data suggest that EoE severity can depend on genotypic differences that increase in vivo exposure to TGFß1. TGFß1 inhibition may be a useful therapy in subsets of EoE patients.

Resolution of remodeling in eosinophilic esophagitis correlates with epithelial response to topical corticosteroids.

BACKGROUND: Esophageal remodeling occurs in eosinophilic esophagitis (EE) patients but whether the components of remodeling in the subepithelium are reversible by administration of topical oral corticosteroids is unknown. METHODS: We quantitated the degree of lamina propria remodeling in esophageal biopsies obtained before and after at least 3 months of therapy with budesonide in 16 pediatric EE subjects. In addition, we investigated whether corticosteroid therapy modulated vascular activation (expression of VCAM-1; level of interstitial edema), TGFbeta(1) activation (levels of TGFbeta(1), phosphorylated Smad2/3), and performed a pilot analysis of a polymorphism in the TGFbeta(1) promoter in relation to EE subjects who had reduced remodeling with budesonide therapy. RESULTS: EE subjects were stratified based on the presence (n = 9) or absence (n = 7) of decreased epithelial eosinophilia following budesonide. Patients with residual eosinophil counts of

Germline characterization of early-aged onset of hereditary non-polyposis colorectal cancer.

OBJECTIVES: Hereditary non-polyposis colorectal cancer (HNPCC) is characterized by the early onset of colorectal cancer (approximately 40 years). Adolescent colorectal cancer is unusual in HNPCC families. We speculated that some DNA mismatch repair germline mutations might be associated with early onset of disease. STUDY DESIGN: Genomic DNA was extracted from members of a kindred with virulent HNPCC fitting the Amsterdam Criteria for HNPCC and sequenced for 2 DNA mismatch repair genes, hMSH2 and hMLH1. A sigmoid adenocarcinoma from the 14-year-old proband was analyzed for highfrequency microsatellite instability and immunostained for DNA mismatch repair gene expression. RESULTS: A germline mutation was identified at nucleotide 676 (codon 226) of the hMLH1 gene. The C to T transition created a nonsense mutation, truncating the hMLH1 protein. This mutation also alters the splice donor sequence, because nucleotide 676 is 2 base pairs from the 3' end of the exon 8. The proband's tumor demonstrated high-frequency microsatellite instability and displayed loss of hMLH1 expression, indicating bi-allelic inactivation of hMLH1. CONCLUSIONS: A complex mutation of hMLH1 at codon 226 is associated with adolescent onset of colorectal cancer in an HNPCC family. Genetic screening of other suspected HNPCC families with unusually young members with cancer might reveal certain genotypes with particularly virulent forms of this disease.

Supernumerary ring chromosomes derived from the long arm of chromosome 12 as the primary cytogenetic anomaly in a rare soft tissue chondroma.

Supernumerary ring chromosomes varying with respect to both size and number were found as the primary cytogenetic anomaly in a rare benign soft tissue chondroma resected from the floor of the mouth of a 3-year-old girl. Reverse fluorescence in situ hybridization paint probes prepared by polymerase chain reaction from microdissected rings produced fluorescent signal over two large but discontinuous parts of the chromosome 12 long arm, subdivided into four regions. This case expands the spectrum of mesenchymal neoplasms in which ring chromosomes have been described as the primary genetic anomaly. A review of the literature reporting similar findings in other soft tissue tumors further supports the possibility that low-level amplification of chromosome 12 long-arm regions may contribute to abnormal cellular proliferation in a variety of mesenchymal tumors. Genes implicated in the control of the cell cycle such as sarcoma amplified sequence (SAS), the human homolog of the murine double-minute type 2 gene (MDM-2), proto-oncogenes CHOP/GADD153, GLI, A2MR, cyclin-dependent kinase (CDK4), and the high mobility group (HMGIC) gene implicated in mesenchymal tumorigenesis are all located on the long arm of chromosome 12. Chromosomal abnormalities involving the 12q13-q15 region are associated with a wide range of benign soft tissue tumors and sarcomas.

Genetic heterogeneity in familial juvenile polyposis.

Juvenile polyposis syndrome (JPS) is an autosomal dominant syndrome characterized by multiple gastrointestinal hamartomatous polyps in the absence of the extraintestinal features that are classic for other hamartomatous polyposis syndromes, such as Bannayan-Riley-Ruvalcaba syndrome (BRRS) and Cowden disease (CD). About 50% of BRRS and >80% of CD demonstrate germ-line mutations in the tumor suppressor and dual phosphatase, PTEN. Germ-line mutation of PTEN as a cause for JPS in a child is controversial because extraintestinal manifestations that would exclude JPS could appear after adolescence, altering the clinical diagnosis. Here, we investigated a family in which the 55-year-old father, who lacks thyroid or skin findings characteristic of CD, demonstrated a germ-line mutation in PTEN that was passed to identical twin daughters, who both manifested JPS. The mutation was a deletion of five bases beginning seven bases from the start of exon 4 of PTEN, which caused aberrant transcripts by reverse transcription-PCR that were absent from a normal individual. Thus, mutations in PTEN are associated with JPS in addition to CD and some BRRS families, although the incidence of PTEN germ-line mutations in JPS might be more rare than that reported for SMAD4, a gene found to be mutated in approximately one-half of the JPS families investigated.

Rhabdomyolysis associated with acute varicella infection.

We report two cases of intense, generalized rhabdomyolysis complicating varicella-zoster virus (VZV) infections, one in an adolescent and one in a young adult male. In both cases, myoglobinuria and weakness of large muscle groups developed within 5 days of the onset of vesicular lesions. A muscle biopsy from one of the individuals showed muscle fiber necrosis in the absence of acute inflammatory infiltrates or vasculitis. Culture of the muscle biopsy specimen for VZV was negative; however, the VZV genome was detected by the polymerase chain reaction. Both patients recovered fully after treatment with hydration therapy alone.

Recurrence of diaphragmatic agenesis associated with multiple midline defects: evidence for an autosomal gene regulating the midline.

We report the familial occurrence of diaphragmatic agenesis in association with other midline anomalies in a brother and sister. Opitz and Gilbert [Am J Med Genet 1982, 12:443-455] introduced the concept of the midline as a developmental field, and there have been reports of pedigrees compatible with the hypothesis of an X-linked gene regulating the development of the midline. This family suggests that an autosomal gene also contributes to the morphogenesis of midline structures.

Histopathological findings in a male with late-onset ornithine transcarbamylase deficiency.

Late onset of symptoms in a 12 1/2-year-old male with ornithine transcarbamylase (OTC) deficiency were associated with unusual histological features in the liver. The patient presented with an acute onset of hyperammonemia and altered mental status after a 2-day prodrome of vomiting and lethargy. Physical examination showed a combative and disoriented male with icteric sclerae but with no fever or hepatomegaly. The plasma ammonia level was 282 microM. Enzyme assays of liver tissue obtained by percutaneous needle biopsy showed OTC activity of approximately 3% of normal; carbamyl phosphate synthetase was normal. Histopathological findings included severe microvesicular centrilobular steatosis. Hepatic architecture and reticulin framework were well preserved. Many hepatocyte nuclei were filled with glycogen. Electron microscopy showed mitochondria that were rounded and expanded with cristae at the edge of the mitochondrial membrane. In contrast to other reports, only slight variations in size and shape were seen. Megamitochondria and intramatrical paracrystalline inclusions were not identified. The cytoplasm contained scattered fat globules, peroxisomes, and dilated smooth endoplasmic reticulum. The prominent mitochondrial abnormalities commonly found in OTC deficiency were notably absent.