Localised massive tumourous xanthomatosis of the small intestine

INTRODUCTION

There are various disorders of the intestine described with accumulations of vacuolated macrophages including single or multiple xanthelasmata, Wolman's disease, cholesteryl ester storage disease (CESD), xanthomatogranulomatotic disease and xantheloma disseminatum.

CLINICAL CASE

In this paper, we report on an exceptional case of a 68-year-old male patient with a localised, massive accumulation of vacuolated, most likely lipid-loaded macrophages with an infiltrative pattern in the muscularis mucosa and propria of the small intestine leading to a tumourous mass requiring surgical removal due to impaired gut function. No enlargement of the liver or the spleen and no evidence of general abnormal lipid storage were detected elsewhere. No evidence of Wolman's or CESD was present. Also, on the ultra-structural level, the macrophages contained no cholesterol clefts typical for either Wolman's and CESD. Instead, largely empty, partly large vacuoles were seen, which most likely contained fatty acids removed during processing.

DISCUSSION

The pathogenetic mechanism of the massive local accumulation of histiocytic cells in this part of the intestine in our case remains un-clear. In summary, this case demonstrates that on rare occasions histiocytic proliferations can mimic tumourous masses with severe functional impairment of the intestine and thus should be in the differential diagnosis of gastrointestinal motility disorders.

[Histopathological examination of joint degeneration: typing, grading and staging of osteoarthritis]

Degenerative arthropathy (osteoarthritis) is one of the most common diseases in modern western societies, in particular in the elderly. The classification and grading of changes during cartilage degeneration represent complex endeavors which are only of limited value in daily pathological practice. In general, the process of joint destruction can always be evaluated for the determining pathogenesis ("typing"), extent ("staging") and degree of the most extensive focal damage ("grading"). However, for routine use one might best restrict description and reporting to the most essential features. This is in particular true for specimens obtained from endoprosthetic surgery (hips and knees), because there is currently no specific clinical relevance for further evaluation. Only the identification of secondary types of degenerative changes, such as those due to unknown rheumatoid disease, gout or extensive osteonecrosis, is of particular interest to the clinical colleague (i.e. typing of the joint lesion).

Evaluation of VEGF A expression and microvascular density as prognostic factors in extrahepatic cholangiocarcinoma

OBJECTIVES

Angiogenesis is essential for tumor growth and metastasis. An association between microvessel density, a measure of tumor angiogenesis, and conventional prognostic variables has been shown for many different tumor entities. In extrahepatic cholangiocarcinoma, the VEGF expression and microvessel density have rarely been investigated.

METHODS

Paraffin-embedded specimens from 51 resected adenocarcinomas of the extrahepatic bile duct were immunostained for vascular endothelial growth factor A (VEGF A) and CD 34 to evaluate the microvessel density (MVD). VEGF A staining was evaluated by combining intensity and percentage of positive tumor cells, as low (expression equal or below the median), or high (above the median). Microvessel density was assessed using a method published by Weidner et al.

RESULTS

Median disease free survival (DFS) of the study group was 12.5 months (range, 1-66.3 months). DFS was calculated in the 39 patients with complete resection. It was significantly better in patients with low microvessel density than DFS in patients with high microvessel density (33 months (range, 3-66.3 months) vs. 21.8 months (range, 1.6-31.6 months); p=0.022). In contrast, VEGF A expression did not correlate with survival. There was a trend toward a higher VEGF A expression in highly vascularized tumors (p=0.08), but failed to reach statistic significance.

CONCLUSIONS

The present study indicates, that vascularisation has an important impact on survival of extrahepatic cholangiocarcinoma patients. Other molecules than VEGF A are probably involved in neovascularization in extrahepatic cholangiocarcinoma.

Synergistic effect of IGF-1 and OP-1 on matrix formation by normal and OA chondrocytes cultured in alginate beads

OBJECTIVE

Growth factor therapy may be useful for stimulation of cartilage matrix synthesis and repair. Thus, the purpose of our study was to further understand the effect of combined insulin-like growth factor-1 (IGF-1) and osteogenic protein-1 (OP-1) treatment on the matrix synthesized by human adult normal and osteoarthritic (OA) chondrocytes.

DESIGN

Chondrocytes were isolated post-mortem from articular cartilage from tali of normal human donors and femoral condyles of OA patients undergoing knee replacement surgery. Cells were cultured in alginate beads for 21 days in four experimental groups: (1) "mini-ITS" control; (2) 100 ng/ml IGF-1; (3) 100 ng/ml OP-1; (4) IGF-1+OP-1, each at 100 ng/ml. Beads were processed for histological (Safranin O and fast green), morphometrical and immunohistochemical (aggrecan, decorin, type I, II, VI, and X collagens, and fibronectin accumulation) analyses.

RESULTS

Histology showed that IGF-1 alone did not induce substantial matrix production. OP-1 alone caused a considerable matrix formation, but the highest matrix accumulation by normal and OA chondrocytes was found when OP-1 and IGF-1 were added together. Morphometrical analysis indicated larger matrices produced by OA chondrocytes than by normal cells under the combined treatment. All tested matrix proteins were more abundant in the combination group. Type X collagen was detected only under the combined OP-1 and IGF-1 treatment and was present at very low levels. Type I collagen was found only in OA chondrocytes.

CONCLUSIONS

The results obtained in the current study suggest that combined therapy with IGF-1 and OP-1 may have a greater potential in treating cartilage defects seen in OA than use of either growth factor alone.

Pathobiology of osteoarthritis: pathomechanisms and potential therapeutic targets

Osteoarthritis, a degenerative joint disease, is the most disabling condition of the Western world. It affects first and foremost the articular cartilages and leads to a molecular and supramolecular destruction of the extracellular cartilage matrix. In addition, the cells, the chondrocytes, show severe alterations of their phenotype: they get anabolically and catabolically activated, change accordingly their gene expression pattern, lose their differentiated phenotype, and undergo focally cell death and cell degeneration. All these processes represent potential targets for therapeutic intervention and drug development. Apart from the cartilage itself, however, other joint tissues are also involved in the disease: thus, the synovial capsule and membrane as well as the subchondral bone account not only for most of the symptoms of the disease, but are also presumably involved in the progression of the degenerative process. Both, inflammation and stiffening within the joint capsule accelerate joint destruction. Stiffening of the subchondral bone increases the mechanical stress over the overlying cartilage during physiological movement. Altogether, there is a plethora of tissues, disease processes and targets for treating osteoarthritic joint degeneration, which will need to be followed up systematically in the future.

Artificial organs: a new option for treating osteoarthritis

Osteoarthritis is usually regarded as a localized disease whose optimal treatment is a therapy applied directly to the affected joint. Unfortunately, current local therapies such as repeated intraarticular injections or constant infusions are associated with a higher risk of infection. One way to overcome this would be to transfer substances made locally by cells within the joint. However, attempts using direct vector transfers or intraarticular injections of ex vivo modified cells could not achieve a sustained protein secretion over several months. Another method of delivering biological factors (i.e.growth hormones) intraarticularly is to transplant an artificial organ, capable of supporting the regeneration of natural cartilage, directly into the affected joint The main difficulty of having to produce bioactive factors over a long period of time is overcome by implanting a chamber-like system filled with either genetically modified cells or a drug-releasing matrix. This drug delivery system would be located at a peripheral site of the joint and could release substances directly into the joint cavity which would be transported via the synovial fluid and/or diffused to the chondrocytes or synoviocytes.

Growth Plate Cartilage as Developmental Model in Osteoarthritis Research -Potentials and Limitations

Gene expression analysis including large scale gene expression profiling has become a very basic tool for investigating the pathogenesis of degenerative joint diseases as well as for the search of new drug targets. However, gene expression analysis so far revealed very complex expression patterns rather than a clear picture of molecular changes occurring during the initiation and progression of the disease. To elucidate the molecular changes in osteoarthritis the analysis of the fetal growth plate as a developmental model for phenotypic changes in chondrocytes occurring in osteoarthritis can help in three ways: it allows to interpret gene expression patterns in the context of disease-relevant processes also occurring in developing cartilage (e.g. cell differentiation, proliferation, matrix synthesis, catabolism and calcification), it offers the chance to investigate gene function in these functional contexts by knocking out or overexpressing genes in animals, and it provides a suitable model for testing the effect of therapeutic compounds on these processes within the growing cartilage.

DNA methylation in osteoarthritic chondrocytes: a new molecular target

OBJECTIVE

To review the current knowledge of the mechanism of DNA methylation, its association with transcriptional silencing, possible mechanisms of hyper- and hypomethylation and how epigenetic changes may relate to the pathogenesis of osteoarthritis (OA).

METHODS

Journal literature was searched using Pubmed. Since there are very few publications directly on epigenetic phenomena in OA, the search was extended to give an overview of epigenetic mechanisms as they relate to the molecular mechanisms of the disease.

RESULTS

While the epigenetics of cancer cells have been intensively investigated, little attention has so far been paid as to whether epigenetic changes contribute to the pathology of non-neoplastic diseases such as OA. This review explains the mechanisms of DNA methylation, its role in transcriptional regulation, and possible demethylation mechanisms that may be applicable to OA. Preliminary evidence suggests that changes in DNA methylation, together with cytokines, growth factors and changes in matrix composition, are likely to be important in determining the complex gene expression patterns that are observed in osteoarthritic chondrocytes.

CONCLUSION

Early evidence points to a role of epigenetics in the pathogenesis of OA. Since epigenetic changes, although heritable at the cellular level, are potentially reversible, epigenetics could be a new molecular target for therapeutic intervention, especially early in the disease.

Osteoarthritis: aging of matrix and cells--going for a remedy

It has been known for a very long time that aging is the most prominent risk factor for the initiation and progression of osteoarthritis. This might be related to continuous mechanical wear and tear and/or result from time/age-related modifications of cartilage matrix components. Also a mere loss of viable cells over time, due to apoptosis or any other mechanism, might contribute. More recent evidence, however, supports that stressful conditions for the cells might promote chondrocyte senescence and might be in particular important for the progression of the osteoarthritic disease process. One of the most important implications of this hypothesis is that it points to issues of cellular degeneration as the basis for understanding of the initiation and the progression of osteoarthritis. Equally important, it emphasizes that whatever treatment we envisage for osteoarthritis, we must take into account that we are dealing with aged/(pre)senescent cells which no longer have the abilities of their juvenile counterparts to respond to the many mechanical, inflammatory, and traumatic assaults to the tissue. Thirdly, this directs treatment options to deal with the senescence of cells, which are only conceptually available today. Clearly, if accumulation of wear and tear over time is the major scenario of osteoarthritis, any therapy will largely be hopeless as moving and loading the joints is unavoidable as implication of their use. However, this review intends to open up the idea that age-related changes are less a fate, but rather a challenge for therapeutic intervention which can be taken.

Primary intraosseous meningioma of the mandible: CT and MR imaging features

We describe the rare entity of an intraosseous meningioma arising in the mandible. The meningioma was found incidentally in an asymptomatic adult patient on dental radiography, mimicking other cystic-appearing jaw masses. The CT and MR imaging features of mandibular meningioma are reviewed with reference to prior published descriptions of this unusual entity.

[Histogenesis of the skeleton and morphogenesis of cartilage-forming neoplasias]

AIMS

Fetal skeletogenesis has been extensively investigated in the vertebrates and both, cellular phenotypes and regulatory mechanisms are well characterized. This knowledge has been used in the past years to elucidate the biology of mesenchymal neoplasias of the skeleton, in particular of the cartilage forming tumors.

RESULTS

The hallmark of chondrogenic tumors is the presence of cells, which can show the full differentiation potential of physiologic chondrocytes depending on the tumor entity investigated. The phenotypic plasticity of chondrocytes explains the striking heterogeneity of cells and extracellular matrix found not only in between different, but also within chondrogenic tumor types. Hereditary exostosis is one example for which genetic analysis as well as the knowledge of regulatory pathways have contributed to our understanding of tumor development: the deficiency in functional EXT gene products explains the pathogenesis of these neoplasms.

CONCLUSIONS

In principle, chondrogenic neoplasias follow differentiation rules delineated during fetal skeletogenesis. Tumor classifications, so far based only on histomorphological criteria can be extended by molecular markers, which have the potential to contribute to a biology-orientated classification of skeletal neoplasms

[Spontaneous and post-therapeutic cartilage repair: evaluation criteria]

Articular cartilage has poor reparative capacities, and once damaged cartilage lesions remain chronic and can lead to osteoarthritis. Over the last decade, several innovative therapies have been introduced to promote the regeneration of articular cartilage while sustaining sufficient mechanical stress and permitting a pain free motion. An important measure of outcome is the morphological characterization of the repair tissue in order to allow for cross-study evaluation. The International Cartilage Repair Society has developed a analogue visual scale to quantify repair tissue, which is described in this paper.

IL-1beta and BMPs--interactive players of cartilage matrix degradation and regeneration

Intact human adult articular cartilage is central for the functioning of the articulating joints. This largely depends on the integrity of its extracellular matrix, given the high loading forces during movements in particular in the weight-bearing joints. Unlike the first impression of a more or less static tissue, articular cartilage shows - albeit in the adult organism a slow--tissue turnover. Thus, one of the most important questions in osteoarthritis research is to understand the balance of catabolic and anabolic factors in articular cartilage as this is the key to understand the biology of cartilage maintenance and degeneration. Anabolic and catabolic pathways are very much intermingled in articular cartilage. The balance between anabolism and catabolism is titrated on numerous levels, starting from the mediator-synthesizing cells which express either catabolic or anabolic factors. Also, on the level of the effector cells (i.e. chondrocytes) anabolic and catabolic gene expression compete for a balance of matrix homeostasis, namely the synthesis of matrix components and the expression and activation of matrix-degrading proteases. Also, there are multiple layers of intracellular cross-talks in between the anabolic and catabolic signalling pathways. Maybe the most important lesson from this overview is the notion that the anabolic-catabolic balance as such counts and not so much sufficient net anabolism or limited catabolism alone. Thus, it might be neither the aim of osteoarthritis therapy to foster anabolism nor to knock down catabolism, but the balance of anabolic-catabolic activities as a total might need proper titration and balancing.

IL-1β, but not BMP-7 leads to a dramatic change in the gene expression pattern of human adult articular chondrocytes—Portraying the gene expression pattern in two donors

Anabolic and catabolic cytokines and growth factors such as BMP-7 and IL-1beta play a central role in controlling the balance between degradation and repair of normal and (osteo)arthritic articular cartilage matrix. In this report, we investigated the response of articular chondrocytes to these factors IL-1beta and BMP-7 in terms of changes in gene expression levels. Large scale analysis was performed on primary human adult articular chondrocytes isolated from two human, independent donors cultured in alginate beads (non-stimulated and stimulated with IL-1beta and BMP-7 for 48 h) using Affymetrix gene chips (oligo-arrays). Biostatistical and bioinformatic evaluation of gene expression pattern was performed using the Resolver software (Rosetta). Part of the results were confirmed using real-time PCR. IL-1beta modulated significantly 909 out of 3459 genes detectable, whereas BMP-7 influenced only 36 out of 3440. BMP-7 induced mainly anabolic activation of chondrocytes including classical target genes such as collagen type II and aggrecan, while IL-1beta, both, significantly modulated the gene expression levels of numerous genes; namely, IL-1beta down-regulated the expression of anabolic genes and induced catabolic genes and mediators. Our data indicate that BMP-7 has only a limited effect on differentiated cells, whereas IL-1beta causes a dramatic change in gene expression pattern, i.e. induced or repressed much more genes. This presumably reflects the fact that BMP-7 signaling is effected via one pathway only (i.e. Smad-pathway) whereas IL-1beta is able to signal via a broad variety of intracellular signaling cascades involving the JNK, p38, NFkB and Erk pathways and even influencing BMP signaling.

B-Zell-Lymphome des Hodens

The occurrence of primary non-Hodgkin's lymphomas of the testes is described in just a few studies in the urological literature. The clinical symptomatology and especially the treatment concept for this relatively rare tumor entity are hardly discussed. Imaging diagnostics, e.g., with CT or MRI, play a decisive role in determining the diagnosis and whether a primary testicular disease is involved or a generalized systemic disease. In cases of primary B-cell lymphomas of the testes, a high inguinal orchiectomy should be performed for diagnostic and therapeutic purposes. The standard chemotherapy for aggressive non-Hodgkin's lymphomas is the CHOP regimen consisting of cyclophosphamide, doxorubicin, vincristine, and prednisone. This article presents two adults aged 67 and 75 years with histologically proven B-cell lymphoma of the testes and discusses the characteristics of this relatively rare clinical picture as well as treatment and prognosis.

Bone morphogenetic protein-7 expression and activity in the human adult normal kidney is predominantly localized to the distal nephron

Bone morphogenetic protein-7 (BMP)-7 plays an important role during fetal kidney development. In the adult, BMP-7 is most strongly expressed in the kidney compared to other organs, but the exact expression pattern as well as the function of BMP-7 is unclear. The major aim of the present study was to define which parts of the human kidney do physiologically express BMP-7 and which cells appear to be targets of BMP activity by showing phosphorylated BMP-receptor-associated Smads 1, 5, or 8 and inhibitor of differentiation factor 1 (ID1) expression. BMP-7 expression was localized by immunohistology to the epithelia of the distal tubule as well as the collecting ducts (CDs). Phospho-Smads 1/5/8 and ID1 expression largely colocalized with BMP-7 and was also localized in the epithelia of the distal tubule and the CDs. This was confirmed by polymerase chain reaction-based mRNA expression analysis. In vitro, proximal tubular cells (PTCs) expressed BMP receptors and BMP-receptor-associated Smads and were reactive to BMP-7. Our data indicate that BMP-7 expression in the adult human kidney appears to be more restricted than in the fetal situation and predominantly found in the distal nephron. Also, evidence of in vivo BMP signalling (i.e. phospho-Smads and ID1 expression) was found there. These findings suggest that BMP-7 plays a physiological role mostly in this part of the kidney. Still, as reported previously, PTCs are responsive to BMP-7, but presumably not in an autocrine or paracrine mode in normal adult kidneys.

Proposal for a histopathological consensus classification of the periprosthetic interface membrane

AIMS

The introduction of clearly defined histopathological criteria for a standardised evaluation of the periprosthetic membrane, which can appear in cases of total joint arthroplasty revision surgery.

METHODS

Based on histomorphological criteria, four types of periprosthetic membrane were defined: wear particle induced type (detection of foreign body particles; macrophages and multinucleated giant cells occupy at least 20% of the area; type I); infectious type (granulation tissue with neutrophilic granulocytes, plasma cells and few, if any, wear particles; type II); combined type (aspects of type I and type II occur simultaneously; type III); and indeterminate type (neither criteria for type I nor type II are fulfilled; type IV). The periprosthetic membranes of 370 patients (217 women, 153 men; mean age 67.6 years, mean period until revision surgery 7.4 years) were analysed according to the defined criteria.

RESULTS

Frequency of histopathological membrane types was: type I 54.3%, type II 19.7%, type III 5.4%, type IV 15.4%, and not assessable 5.1%. The mean period between primary arthroplasty and revision surgery was 10.1 years for type I, 3.2 years for type II, 4.5 years for type III and 5.4 years for type IV. The correlation between histopathological and microbiological diagnosis was high (89.7%), and the inter-observer reproducibility sufficient (85%).

CONCLUSION

The classification proposed enables standardised typing of periprosthetic membranes and may serve as a tool for further research on the pathogenesis of the loosening of total joint replacement. The study highlights the importance of non-infectious, non-particle induced loosening of prosthetic devices in orthopaedic surgery (membrane type IV), which was observed in 15.4% of patients.

CDRAP is expressed in adult articular cartilage, but its expression is not significantly regulated in osteoarthritic chondrocytes

OBJECTIVE

In this study we assessed the differential in vivo mRNA expression levels of CDRAP, a potential marker of cartilage degeneration.

METHODS

Conventional and real time PCR in a large series of normal (n = 18) and late stage osteoarthritic (n = 24) cartilage specimens were performed.

RESULTS

Conventional PCR analysis could demonstrate the presence of CDRAP mRNA in normal and osteoarthritic chondrocytes. Real time quantitative PCR confirmed the presence of CDRAP mRNA expression in normal articular chondrocytes in vivo (and in vitro). No significant up-regulation of CDRAP was observed in osteoarthritic chondrocytes in vivo.

CONCLUSION

The presented results confirm expression of CDRAP by normal and osteoarthritic articular chondrocytes, but indicate that increased expression levels by chondrocytes are not the cause of the increased levels of CDRAP in the synovial fluid of patients with osteoarthritis.

EXT-related pathways are not involved in the pathogenesis of dysplasia epiphysealis hemimelica and metachondromatosis

Dysplasia epiphysealis hemimelica (DEH) and metachondromatosis (MC) are considered in the differential diagnosis of solitary and hereditary osteochondromas. Both are rare disorders with DEH demonstrating cartilaginous overgrowth of an epiphysis and MC exhibiting synchronous enchondromas and osteochondromas. Ten cases of DEH and two of MC were compared with osteochondromas at the histological and molecular level. Histologically, clumping of chondrocytes within a fibrillary chondroid matrix is characteristic of DEH, while osteochondromas and MC display the characteristic growth plate architecture. Using cDNA microarray analysis we demonstrate that DEH and MC cluster separately from osteochondromas and growth plates. The EXT genes, involved in the hereditary multiple osteochondromas syndrome, and downregulated in osteochondroma, were normally expressed in DEH and MC as shown by quantitative reverse transcriptase-polymerase chain reaction (qPCR). EXT is involved in heparan sulphate biosynthesis, important for Indian Hedgehog/ParaThyroid Hormone Like Hormone (IHH/PTHLH) growth plate signalling pathways. IHH/PTHLH signalling molecules were expressed in DEH and MC as shown by both qPCR and immunohistochemistry, suggesting that this pathway is active. This is in contrast to osteochondroma, in which PTHLH signalling is downregulated. Thus, lesions of DEH and MC are separate entities from osteochondroma as confirmed by their different cDNA and protein expression profiles. Downstream targets of EXT, which are downregulated in osteochondroma, are expressed in DEH and MC, suggesting that EXT signalling is not disturbed.

Osteoarthritis: pathobiology-targets and ways for therapeutic intervention

Osteoarthritis is first and foremost the ongoing destruction of the articular cartilages of joints. Therefore, the extracellular matrix and the cells of the articular cartilages are the primary targets of osteoarthritis therapy. This tries to inhibit enzymatic destruction of the extracellular cartilage matrix as well as the modification of the cellular phenotype of the chondrocytes: cell degeneration and cell death are alongside anabolic activation and stabilization of the cellular phenotype of major interest. However, apart from the cartilage and its cells, other tissues of the joints are also important for the symptoms of the disease, which basically all originate outside the articular cartilage. In addition, changes in the subchondral bone as well as the synovial capsule and membrane are important at least for the progression of the disease process. All the named tissues offer different directions and ways for therapeutic intervention.

MMP-9/gelatinase B is a gene product of human adult articular chondrocytes and increased in osteoarthritic cartilage

OBJECTIVE

Collagen fibril degeneration involves initially the cleavage within the triple helix by the collagenases 1 (MMP-1) and 3 (MMP-13), but then mainly involves also the gelatinases A (MMP-2) and B (MMP-9). The objective of this study was to determine the quantitative expression levels as well as the distribution in normal and osteoarthritic cartilage of gelatinase B and in cultured articular chondrocytes with and without stimulation by Il-1Beta.

METHODS

Conventional and real-time quantitative PCR technology and immunohistochemistry were used to determine gelatinase B expression on the mRNA and protein level.

RESULTS

Conventional PCR analysis could demonstrate the presence of gelatinase B mRNA only in osteoarthritic chondrocytes. Real-time quantitative PCR confirmed the increased expression of gelatinase B mRNA expression in osteoarthritic chondrocytes. No significant up-regulation of gelatinase B was observed by Il-1Beta. Immunostaining for gelatinase B showed the presence of gelatinase B in a subset of normal and in a large portion of osteoarthritic chondrocytes with a more extended distribution in the latter.

CONCLUSION

In osteoarthritic cartilage destruction, gelatinase B is involved in collagen destruction though still at a very much lower level than gelatinase A. Only a very small subset of normal adult articular chondrocytes express gelatinase B in vivo suggesting that gelatinase B unlike gelatinase A is hardly or only very focally involved in physiological collagen turnover.