An 8-cM interstitial deletion on 4q21-q22 in DNA from an infant with hepatoblastoma overlaps with a commonly deleted region in adult liver cancers

We performed molecular analysis of a germline interstitial deletion of chromosome 4 [del(4)(q21.22q23)], which had been observed in a male infant manifesting early-onset hepatoblastoma (HBL). The chromosomal anomaly in this child was associated with a unique congenital syndrome including HBL, atrial septal defect, ventricular septal defect, patent ductus arteriosus, mental retardation, and seizures. However, the patient did not exhibit a megalencephaly typical of 4q21-22 deletions. His HBL was associated with an increasing serum alpha-fetoprotein level and rapid growth. To define the chromosomal deletion at the molecular level in this child, we analyzed his lymphoblasts with fluorescence in situ hybridization, using as probes a panel of BAC/PAC genomic clones containing STS markers covering the 4q12-27 region. The analysis revealed that the affected chromosome had an 8-cM deletion within 4q21-q22, flanked by markers D4S2964 and D4S2966. This microdeletion overlaps with the commonly deleted region at 4q21-q22 that was recently defined in adult hepatocellular carcinomas.     

An autopsy case of idiopathic enlargement of the right atrium, and a review of the literature

A 69-year-old man in whom idiopathic enlargement of the right atrium was revealed at autopsy is described. The patient had had cardiomegaly of at least 19 years' duration prior to his death, even though cardiac symptoms were absent. Cause of death was pancreatic carcinoma. Postmortem examination revealed marked and diffuse dilatation of the right atrium and moderate dilatation of the left atrium. Measurement of the cardiac chambers showed that the right and left atria were 7.6 and 4.7 times as large as those of normal hearts, respectively. The volume of either ventricle was about twice the normal value. Histologically, widespread cardiac muscular degeneration and necrosis, diffuse fibrosis, and focal lymphocytic infiltration were found in the right atrium and also, to a lesser degree, in the left atrium. Such pathologic changes were not found in either of the ventricles. The etiology of these muscular changes, which might have been related to atrial enlargement, was unclear. The present case was thought to be consistent with idiopathic enlargement of the right atrium, and a brief review of the literature is given.     

Gallbladder adenocarcinoma arising in Rokitansky–Aschoff sinus

Carcinoma arising from Rokitansky–Aschoff sinus (RAS) is extremely rare; only eight cases have been reported in the literature. Herein is reported a case of minute adenocarcinoma arising in RAS. A 77‐year‐old Japanese man with gallbladder stones underwent cholecystectomy. A tiny submucosal tumor (1 cm × 1 cm) was incidentally recognized. Histologically, the submucosal tumor was located in the subserosa and, to a lesser extent, in the fibromuscular layer. It was adenocarcinoma. RAS were recognized within the tumor, and there was a gradual transition between RAS and the adenocarcinoma. Mucin histochemistry indicated neutral and acidic mucins in the cytoplasm and lumens of the adenocarcinoma cells. Immunohistochemistry showed that the adenocarcinoma cells were positive for cytokeratin, epithelial membrane antigen, carbohydrate antigen 19‐9, K‐i67 (labeling = 80%), MUC1, MUC5AC and MUC6. In contrast, the adenocarcinoma cells were negative for CEA, c‐erbB2, p53 protein, MUC2 and CD10. In summary, minute subserosal adenocarcinoma, which arose in RAS, was found incidentally; therefore careful examination of resected gallbladders is necessary.     

Cartilage engineering from ovine umbilical cord blood mesenchymal progenitor cells

We aimed to determine whether three-dimensional (3D) cartilage could be engineered from umbilical cord blood (CB) cells and compare it with both engineered fetal cartilage and native tissue. Ovine mesenchymal progenitor cells were isolated from CB samples (n=4) harvested at 80-120 days of gestation by low-density fractionation, expanded, and seeded onto polyglycolic acid scaffolds. Constructs (n=28) were maintained in a rotating bioreactor with serum-free medium supplemented with transforming growth factor-beta1 for 4-12 weeks. Similar constructs seeded with fetal chondrocytes (n=13) were cultured in parallel for 8 weeks. All specimens were analyzed and compared with native fetal cartilage samples (n=10). Statistical analysis was by analysis of variance and Student's t-test (p<.01). At 12 weeks, CB constructs exhibited chondrogenic differentiation by both standard and matrix-specific staining. In the CB constructs, there was a significant time-dependent increase in extracellular matrix levels of glycosaminoglycans (GAGs) and type-II collagen (C-II) but not of elastin (EL). Fetal chondrocyte and CB constructs had similar GAG and C-II contents, but CB constructs had less EL. Compared with both hyaline and elastic native fetal cartilage, C-II and EL levels were, respectively, similar and lower in the CB constructs, which had correspondingly lower and similar GAG levels than native hyaline and elastic fetal cartilage. We conclude that CB mesenchymal progenitor cells can be successfully used for the engineering of 3D cartilaginous tissue in vitro, displaying select histological and functional properties of both native and engineered fetal cartilage. Cartilage engineered from CB may prove useful for the treatment of select congenital anomalies.     

Peripheral hepatolithiasis incidentally found at autopsy

Summary Hepatolithiasis is a common disease in East Asia though very rare in the West. Four cases of hepatolithiasis in which calculi were incidentally found in the peripheral branches of the intrahepatic biliary tree at autopsy are described and compared with hepatolithiasis involving the major branches of the intrahepatic biliary tree. These four cases were all elderly, three patients were male and one female. The calculi were brown pigment stones in each case, as seen in the major branch type. The stone-containing ducts showed mild fibrosis and glandular proliferation with inflammatory changes in three cases; these changes were marked in the fourth case. The hepatic parenchyma around the stone-containing ducts was atrophic or collapsed in all four cases. The major branches of the intrahepatic biliary tree as well as the extrahepatic tree failed to show findings suggestive of bacterial infections or biliary anomalies. These data suggest that brown pigment stones develop primarily in the peripheral ducts in the liver. It remains uncertain whether the peripheral type eventually progresses to the major type or not.     

Genetic basis of autoimmune disease in MRL/lpr mice: dissection of the complex pathological manifestations and their susceptibility loci

MRL/MpJ-lpr/lpr (MRL/lpr) mice spontaneously develop various forms of autoimmune disease in the same individuals, including glomerulonephritis, polyarteritis, arthritis and sialoadenitis. An MRL recombinant congenic strain of mice bearing the gld gene, MRLiMpTn-gld/gld (MRL/gld), also develops lesions similar to those in MRL/lpr mice. The lpr and gld genes are a Fas deletion mutant and a Fas ligand mutant, respectively. Thus, autoimmune disease in these mice seemed to be a single gene disease involving the complex pathological manifestations as pleiotropy. However, comparative studies with C3H/HeJ and C57BL/6J strains of mice bearing lpr or gld revealed that these lesions developed only in mice with an MRL background. Moreover, these lesions were genetically segregated among MRL/lpr x (MRL/lpr x C3H/lpr)F1 mice. This indicates that an MRL strain has particular gene(s) affecting the development of each lesion. Association studies of each lesion with polymorphic microsatellite markers using backcross mice revealed that gene loci responsible for each lesion exist at different chromosomal positions and have additive and hierarchical properties of polygenic inheritance for some of the lesions. We conclude that the complex pathological manifestations of autoimmune disease are under the control of different combinations of polygenes.     

Cell lineage analysis during liver development using the spf(ash)-heterozygous mouse

Biliary epithelial cells differentiate from periportal hepatoblasts during fetal mouse liver development. It remains to be determined whether each hepatoblast is equivalent for differentiation into hepatocytes and biliary epithelial cells in normal liver development. To resolve this question, the mosaic pattern of ornithine transcarbamylase (OTC) expression was analyzed in the hepatoblast population of spf(ash) (sparse-fur with abnormal skin and hair)-heterozygous fetal mouse livers, in which random inactivation of either the X chromosome carrying the spf(ash) gene (causing OTC deficiency) or its wild-type gene occurs. Aggregates (patches) of OTC-positive hepatoblasts showed very complex patterns, and their shapes and size distributions were similar in sections from periportal regions and nonperiportal regions of the fetal liver in which bile duct differentiation by periportal hepatoblasts occurred. Average sizes of periportal patches were larger than those of nonperiportal patches because of the presence of more hemopoietic cells in the latter region. The OTC mosaicism in periportal bile duct progenitors and hepatoblast islands of other liver parenchyma was also similar. These results suggest that the growth patterns of hepatoblasts are similar in both periportal and nonperiportal regions. Isolated three-dimensional patches comprising hepatoblasts giving rise to only biliary epithelial cells or hepatoblasts giving rise to both hepatocytes and biliary epithelial cells were observed in periportal regions. In nonperiportal regions, patches consisting of hepatoblasts differentiating into hepatocytes were also seen. Thus, it is likely that there are three lineages for the developmental fates of hepatoblasts: hepatoblasts giving rise to only biliary epithelial cells, hepatoblasts giving rise to only hepatocytes, and hepatoblasts giving rise to both of them.