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Background/aims: Wilson disease is caused by a large number of different mutations in the ATP7B gene. Wilson disease patients from a homogeneous ethnical background (Saxonia) were studied for distribution and phenotypes of ATP7B mutations., Methods: Eighty-two patients were analyzed. The H1069Q mutation was assayed by a polymerase chain reaction-based restriction fragment length polymorphism test. Exons 8 and 15 were sequenced in all, and the entire gene in 30, non-H1069Q-homozygotes., Results: Four novel and 12 known mutations were found. Thirty-two (39%) Wilson disease patients were homozygous and 39 (48%) heterozygous for the H1069Q mutation (allele frequency 63%). Together with sequence analysis of exons 8 and 15 mutations in both alleles were identified in 65% of patients. Only one patient had both mutations at other locations. In H1069Q homozygotes symptoms started later (21.3+/-7.2 years) than in H1069Q compound heterozygotes (14.6+/-5.8, P<0.001) or H1069Q negatives (10+/-4.4, P<0.001), and they had more frequently neurologic symptoms (93 vs. 47%, P<0.001) and Kayser-Fleischer rings (82 vs. 51%, P<0.001). Mutation status did not correlate with liver biopsy findings, serum ceruloplasmin levels or (64)Cu-assay results., Conclusions: In spite of many known ATP7B mutations, only few occur in this homogeneous population. Limited genetic testing is useful to confirm Wilson disease in this population.

This is a case report of a 36 years old man who has been suffering for 20 years from benign recurrent intrahepatic cholestasis (BRIC). BRIC is a rare autosomal recessive disease characterised by prolonged episodes of intrahepatic cholestasis and pruritus alternating with periods of nearly normal liver function, and does not progress to cirrhosis. Since all former approaches to medical treatment of the patients severe pruritus were ineffective, the patient was treated by 3 sessions of albumin dialysis (MARS, Molecular Adsorbents Recirculating System). MARS dialysis decreased serum bilirubin levels by more than 60 % and effectively lowered serum bile acid levels by 45 %. The course of serum parameters was accompanied by a dramatic clinical improvement of the patients symptoms (pruritus, jaundice, fatigue etc.). MARS therapy appeared to shorten the duration of the cholestatic attack.

Malignant tumors with high glucose metabolic rates accumulate [18F]-fluorodeoxyglucose (FDG), a positron emitting tracer. The aim of this study was to evaluate FDG positron emission tomography (PET) for detection and staging of human cholangiocarcinoma (CC). Patients with adenocarcinoma of the biliary tree (n = 26), with benign lesions of the bile ducts (n = 8), and 20 control patients underwent FDG-PET (370 MBq [18F]-FDG, Siemens ECAT EXACT HR(+)). In a blinded fashion, 4 independent experts evaluated the PET scans visually and semiquantitatively using the standardized uptake value and a tumor/non-tumor ratio. All adenocarcinomas and benign lesions (sclerosing cholangitis, bile duct adenoma, Caroli's disease) were histologically proven and imaged by magnetic resonance imaging and endoscopic retrograde cholangioscopy. True-positive PET scans were obtained in 24 of 26 CC and false-negative scans in the other 2 (sensitivity 92.3%). The PET scan was true-negative in 18 of 20 controls and in all 8 benign biliary lesions (specificity 92.9%). Visual and semiquantitative evaluation using tumor/non-tumor ratios were equally accurate (accuracy 92.6%) whereas evaluation by standardized uptake value revealed lower accuracy (P <.05). Regional or hepatoduodenal lymph node metastases were detected with PET in only 2 of 15 cases whereas distant metastases (peritoneal carcinomatosis, pulmonary metastases) were diagnosed in 7 of 10 cases. In conclusion, PET is highly sensitive and specific for the detection and localization of CC. It can be helpful for diagnosis of distant metastases but is not suitable for detection of regional lymph node metastases.

Mutations in the Wilson disease gene ATP7B, a P-type ATPase, are responsible for copper accumulation in the liver and other organs leading to Wilson disease (WD, OMIM 277900). Clinical manifestations of Wilson disease (WD) include chronic liver disease, acute hepatic failure or neuropsychiatric diseases. Since potent medical treatments are available to prevent disabling residual symptoms, early diagnosis is crucial. To demonstrate the clinical course and genetic findings, a male patient with a novel mutation in the ATP7B gene, a 10 base pair insertion in exon 6 (1927ins 10), and a second missense mutation in exon 13 (P992L) is reported. The patient presented with signs of chronic liver disease at the age of 10 years. Clinical findings included hepatomegaly, elevated liver enzymes and coagulopathy. A combination treatment with the copper chelating agent D-penicillamine and zinc acetate was started leading to normalization of liver function and no appearance of neurological signs or Kayser-Fleischer ring after 7 years follow-up. Truncating mutations of the ATP7B gene (insertions, deletions, nonsense mutations) leading to gross loss of C-terminal parts of the protein, thereby probably completely destroying the protein function, may correlate with a hepatic phenotype and early onset as seen in the patient presented.

Adenomatous polyposis coli (APC) mutations are present in >70% of colon cancers. The APC protein binds to beta-catenin (beta-cat), a protein first identified because of its role in E-cadherin (E-cad) cell adhesion. In some colon cancers lacking APC defects, mutations in presumptive glycogen synthase kinase 3beta phosphorylation sites near the beta-cat NH2 terminus appear to render beta-cat resistant to regulation by APC and glycogen synthase kinase 3beta. In cells with APC or beta-cat defects, beta-cat is stabilized and, in turn, binds to and activates T-cell factor (Tcf)/lymphoid enhancer factor (Lef) transcription factors. To further explore the role of APC, beta-cat, Tcf, and E-cad defects in gastrointestinal cancers, we assessed gastric and pancreatic cancers for constitutive Tcf transcriptional activity (CTTA). Two of four gastric and two of eight pancreatic cancer lines showed CTTA. One gastric and one pancreatic cancer had mutations in the NH2-terminal phosphorylation sites of beta-cat. The other gastric cancer with CTTA had a missense mutation at serine 28 of gamma-cat, a potential phosphorylation site in this beta-cat-related protein. Although E-cad is an important binding partner for beta-cat and gamma-cat, E-cad inactivation did not result in CTTA. The beta-cat and gamma-cat mutant proteins identified in our studies strongly activated Tcf transcription in vitro, whereas beta-cat mutant proteins with large NH2-terminal deletions had only modest effects on Tcf. Our results suggest a role for Tcf deregulation in gastric and pancreatic cancer, resulting from beta-cat and gamma-cat mutations in some cases and, in others, from yet to be defined defects. Furthermore, these data imply that the consequences of APC and beta-cat mutations are distinct from the effects of E-cad inactivation.

Beta-Catenin has a critical role in E-cadherin-mediated cell-cell adhesion, and it also functions as a downstream signaling molecule in the wnt pathway. Mutations in the putative glycogen synthase kinase 3beta phosphorylation sites near the beta-catenin amino terminus have been found in some cancers and cancer cell lines. The mutations render beta-catenin resistant to regulation by a complex containing the glycogen synthase kinase 3beta, adenomatous polyposis coli, and axin proteins. As a result, beta-catenin accumulates in the cytosol and nucleus and activates T-cell factor/ lymphoid enhancing factor transcription factors. Previously, 6 of 27 melanoma cell lines were found to have beta-catenin exon 3 mutations affecting the N-terminal phosphorylation sites (Rubinfeld B, Robbins P, Elgamil M, Albert I, Porfiri E, Polakis P: Stabilization of beta-catenin by genetic defects in melanoma cell lines. Science 1997, 275:1790-1792). To assess the role of beta-catenin defects in primary melanomas, we undertook immunohistochemical and DNA sequencing studies in 65 melanoma specimens. Nuclear and/or cytoplasmic localization of beta-catenin, a potential indicator of wnt pathway activation, was seen focally within roughly one third of the tumors, though a clonal somatic mutation in beta-catenin was found in only one case (codon 45 Ser-->Pro). Our findings demonstrate that beta-catenin mutations are rare in primary melanoma, in contrast to the situation in melanoma cell lines. Nonetheless, activation of beta-catenin, as indicated by its nuclear and/or cytoplasmic localization, appears to be frequent in melanoma, and in some cases, it may reflect focal and transient activation of the wnt pathway within the tumor.

Netrins, a family of laminin-related secreted proteins, have critical roles in axon guidance and cell migration during development. The deleted in colorectal cancer (DCC) protein has been implicated as a netrin-1 receptor component. The expression and function of netrins in adult tissues remain unknown, and direct interaction of netrin-1 with DCC has not been demonstrated. We cloned the human netrin-1 (NTN1L) gene, mapped it to chromosome 17p12-13, and found that it encodes a 604 amino acid protein with 98% identity to mouse netrin-1 and 50% identity with the Caenorhabditis elegans UNC-6 protein. NTN1L transcripts were detected in essentially all normal adult tissues studied, and markedly reduced or absent NTN1L expression was seen in approximately 50% of brain tumors and neuroblastomas. In one neuroblastoma, missense mutations at highly conserved NTN1L codons were found. Netrin-1 protein could be cross-linked to DCC protein on the cell surface, but it did not immunoprecipitate with DCC in the absence of cross-linking and it failed to bind to a soluble fusion protein containing the entire DCC extracellular domain. Our findings demonstrating NTN1L loss of expression and mutations suggest that NTN1L alterations may contribute to the development of some cancers. Furthermore, the binding of netrin-1 to DCC appears to depend on the presence of a coreceptor or accessory proteins.

Gastrointestinal (GI) symptoms are part of the most frequent complaints in HIV disease. A methodical effort is required to identify treatable syndromes. Progressive immunodeficiency is associated with increased prevalence of opportunistic or non-opportunistic infections and neoplasms. Dysphagia and odynophagia, in the majority due to candida esophagitis, are best evaluated by endoscopy. In the presence of diarrhea, upper GI endoscopy is indicated if evaluations of stool and endoscopy of the lower GI tract are negative and may uncover proximal small-bowel infection by Cryptosporidium, Microsporidium or Mycobacterium avium. HIV-associated neoplasias (Kaposi's sarcoma, non-Hodgkin lymphomas), not rarely affecting the upper GI tract and sometimes leading to obstruction or bleeding, are reliably diagnosed only by endoscopy. Since visible lesions mostly are nonspecific and normal-appearing mucosa may harbor pathogens, biopsies for pathology and cultures are crucial for correct diagnosis in GI diseases of HIV-infected patients.