Pathogenesis of lymphangiomasWiegand, Susanne; Eivazi, Behfar; Barth, Peter; Rautenfeld, Dirk; Folz, Benedikt; Mandic, Robert; Werner, Jochen
doi: 10.1007/s00428-008-0611-zpmid: 18500536
Based on various hypotheses concerning lymphangiogenesis published in the literature, different putative mechanisms of lymphangioma development are discussed including failure of the lymphatic system to connect with or separate from the venous system, abnormal budding of the lymphatic system from the cardinal vein, or acquired processes such as traumata, infections, chronic inflammations, and obstructions. Increasingly, the possible influence of lymphangiogenic growth factors on the development of lymphangiomas is discussed. The proved expression of different growth factors in the endothelium of lymphangiomas leads to new hypotheses regarding the pathogenesis of lymphangiomas. Thus, further studies on the lymphangiogenesis and the development of lymphangiomas will have to clarify as to whether lymphangiomas are true malformations or neoplastic in nature.
Strategies for optimizing pathologic staging of sentinel lymph nodes in breast cancer patientsMadsen, Eva; Dalen, Jan; Gorp, Joost; Borel Rinkes, Inne; Dalen, Thijs
doi: 10.1007/s00428-008-0601-1pmid: 18563440
Due to the extensive pathologic evaluation of the sentinel lymph node (SLN), micrometastases are frequently observed. If micrometastases are clinically relevant, the histopathologic examination of SLNs should be sensitive enough to detect them. The probability of detecting micrometastases was calculated when examining the SLN according to the current Dutch pathology protocol and strategies evaluated to optimize the chance of detection. The dimensions of 20 consecutive axillary SLNs in patients with cT1-2N0 breast cancer were measured. In a mathematical model, the probability of detecting micrometastases in a SLN was calculated. Similarly, strategies to optimize the probability of detecting micrometastases were explored. When applying the pathology guidelines, the calculated probability to detect a micrometastasis was 18% for a 200-μm micrometastasis and 69% for a 2.0-mm metastasis in a median sized SLN. To detect the smallest micrometastasis in a median-sized SLN with a 95% probability, the interval between the sections must be decreased to 200 μm, and 20 levels from both halves must be examined. Given a prognostic significance of micrometastases, our current pathology guidelines are not sensitive enough. The number of sections should be increased, while the interval between cuts should be no more than 200 μm.
Three German fibrinogen Aα-chain amyloidosis patients with the p.Glu526Val mutationEriksson, Magdalena; Schönland, Stefan; Bergner, Raoul; Hegenbart, Ute; Lohse, Peter; Schmidt, Hartmut; Röcken, Christoph
doi: 10.1007/s00428-008-0619-4pmid: 18500534
Plasma protein fibrinogen variants cause fibrinogen Aα-chain (AFib) amyloidosis, which presents with hypertension, proteinuria, and azotemia. Six AFib mutations have been reported thus far. We identified three patients who presented with marked proteinuria and serum creatinine elevations. Their kidney biopsies revealed destruction of the glomerular architecture by amyloid deposits with typical, apple-green birefringence in polarized light after Congo red staining. We found immunoreactivity against fibrinogen, which is typical for this type of amyloidosis. We sequenced the FGA exon 5 and demonstrated heterozygosity for the p.Glu526Val mutation in all three cases. This amino acid substitution is the most common fibrinogen Aα-chain variant causing AFib amyloidosis. The mutation has been reported in individuals of European and American descent but not yet in German patients. AFib amyloidosis should therefore be considered an important differential diagnosis in German patients with renal amyloidosis. In the cases described here, the use of antibodies directed against fibrinogen, followed by direct gene sequencing, revealed the underlying cause.
Re-expression of nestin in the myocardium of postinfarcted patientsMokry, J.; Pudil, R.; Ehrmann, J.; Cizkova, D.; Osterreicher, J.; Filip, S.; Kolar, Z.
doi: 10.1007/s00428-008-0631-8pmid: 18546018
Intact cardiac muscle cells in the adult heart do not express intermediate filament nestin. In this study, we report on widespread expression of intermediate filament nestin in human myocardium of patients who died from the myocardial infarction. Nestin was detected in cardiomyocytes, endothelial cells, and few interstitial cells. Elevated levels of nestin were observed in cardiac muscle cells in all specimens, although the intensity of immunoreactivity and distribution of the signal differed. The strongest immunoreactivity was observed from 4 days after myocardial infarction in the infarction border zone where nestin was distributed homogeneously in the entire sarcoplasm of cardiac muscle cells. Within the following week, nestin in immunoreactive cardiomyocytes was redistributed and restricted to small subsarcolemmal foci and to intercalated discs. Angiogenic capillaries that grew between vital nestin-positive cardiomyocytes and entered the necrotic area expressed also high levels of nestin. Nestin-positive endothelial cells were often observed in mutual interactions with nestin-positive cardiac muscle cells. These findings document a crucial role of nestin in remodeling cytoskeleton of cells in the human postinfarcted myocardium.
The construction of high-density paraffin tissue microarrays with 0.43-mm-diameter paraffin tissue core biopsies is technically feasibleVogel, Ulrich
doi: 10.1007/s00428-008-0622-9pmid: 18551310
Paraffin tissue microarrays (PTMAs) are blocks of paraffin containing up to 1,000 paraffin tissue core biopsies (PTCBs). The growing number of publications in recent years bears eloquent witness to the advantages of these PTMAs in high-throughput molecular profiling of tumor specimens. In order to conserve the often minute quantities of available tumor tissue with precisely recorded follow-up data and to store the greatest possible number of PTCBs in one block, researchers often try to reduce PTCBs to the smallest possible diameter. Until now, the smallest feasible diameter for PTCBs was 0.6 mm. Experiments with diameters below 0.6 mm have failed due to the instability of the paraffin tissue punch. The process described allows the construction of PTMAs with PTCBs only 0.43 mm in diameter utilizing simple, inexpensive, self-made paraffin tissue punches and predrilled recipient blocks.
Comparison of different techniques for the detection of genetic risk-identifying chromosomal gains and losses in neuroblastomaVillamón, Eva; Piqueras, Marta; Mackintosh, Carlos; Alonso, Javier; Álava, Enrique; Navarro, Samuel; Noguera, Rosa
doi: 10.1007/s00428-008-0633-6pmid: 18574593
Neuroblastoma (NB) is a pediatric neoplasia that shows complex combinations of acquired genetic aberrations. The specific genes and the molecular mechanisms responsible for development and progression of NB remain poorly understood. Our main objective is to compare the results obtained with different techniques for the detection of genomic data in 20 patients with NB using the information obtained to select the appropriate technique in routine analysis for the therapeutic stratification. The genetic methods used in this study are multiprobe fluorescence in situ hybridization (FISH) assay, metaphasic comparative genomic hybridization (mCGH), array comparative genomic hybridization (aCGH), and the multiplex ligation-dependent probe amplification (MLPA). Genomic copy number abnormalities were used to group the cases in four categories: MYCN amplification cases; 11q deletion tumors; cases with partial chromosome gains or losses and samples with entire chromosome alterations. The data obtained from the multigenomic techniques showed a high degree of concordance and our findings support the hypothesis that NB consists of biologically distinct subgroups that differ by genetic characteristics of prognostic relevance. FISH will be essential for the mandatory study of MYCN status. The use of MLPA as routine technique is an advantage procedure for detecting the implication of the common genetic alterations in NB.
Differential expression of fatty acid synthase (FAS) and ErbB2 in nonmalignant and malignant oral keratinocytesSilva, Sabrina; Cunha, Isabela; Rangel, Ana; Jorge, Jacks; Zecchin, Karina; Agostini, Michelle; Kowalski, Luiz; Coletta, Ricardo; Graner, Edgard
doi: 10.1007/s00428-008-0626-5pmid: 18528705
The aim of this study was to investigate fatty acid synthase (FAS) and ErbB2 expression in nonmalignant oral epithelium and oral or head and neck squamous cell carcinomas (OSCC/HNSCC). Morphologically normal, hyperkeratotic, and dysplastic oral epithelium as well as well-differentiated and poorly differentiated OSCC were immunohistochemically evaluated for FAS, ErbB2, and Ki-67. These proteins were also analyzed in a tissue microarray with 55 HNSCC. SCC-9 cells were used to study FAS and ErbB2 during differentiation. FAS expression was higher in hyperkeratosis, dysplasias, and OSCC than in normal epithelium. Well-differentiated OSCC/HNSCC were more positive for FAS than the poorly differentiated tumors. ErbB2 was observed at the surface of nonmalignant and well-differentiated OSCC/HNSCC keratinocytes and in the cytoplasm of poorly differentiated cells. Ki-67 index was progressively higher from normal oral epithelium to OSCC, inversely correlated with cell surface ErbB2, and positively correlated with intracytoplasmic ErbB2. Finally, SCC-9 cell cultures were enriched in membrane ErbB2-positive cells after differentiation by anchorage deprivation. In conclusion, FAS is overexpressed in OSCC/HNSCC and hyperkeratotic oral epithelium and ErbB2 is found at the cell surface of differentiating keratinocytes and in the cytoplasm of poorly differentiated tumor cells. Ki-67 index is higher in epithelial dysplasias and OSCC than in morphologically normal oral epithelium.
Amalgamation of Chlamydia pneumoniae inclusions with lipid droplets in foam cells in human atherosclerotic plaqueBobryshev, Yuri; Killingsworth, Murray; Tran, Dihn; Lord, Reginald
doi: 10.1007/s00428-008-0629-2pmid: 18528704
Chlamydia pneumoniae (Chlamydophila pneumoniae) infect macrophages and accelerates foam cell formation in in vitro experiments, but whether this might occur in human atherosclerosis is unknown. In the present study, we examined 17 carotid artery segments, obtained by endarterectomy, in which the presence of C. pneumoniae was confirmed by both polymerase chain reaction and immunohistochemistry. Electron microscopy demonstrated the presence of structures with the appearance of elementary, reticulate and aberrant bodies of C. pneumoniae in the cytoplasm of macrophage foam cells. The volume of the cytoplasm that was free from vacuoles and lipid droplets in C. pneumoniae-infected foam cells was dramatically reduced, and a phenomenon of the amalgamation of C. pneumoniae inclusions with lipid droplets was detected. Double immunohistochemistry showed that C. pneumoniae-infected foam cells contained a large number of oxidized low-density lipoproteins. The observations provide support to the hypothesis that C. pneumoniae could affect foam cell formation in human atherosclerosis.
Expression and intracellular localization of matrix metalloproteinases in intraductal papillary mucinous neoplasms of the pancreasTamahashi, Urara; Kumagai, Jiro; Takizawa, Touichiro; Sekine, Masaki; Eishi, Yoshinobu
doi: 10.1007/s00428-008-0617-6pmid: 18500535
To analyze the expression of matrix metalloproteinases (MMPs) and their relationships with the histological grades of the intraductal papillary mucinous neoplasm (IPMN) of the pancreas, we examined the frequency of expression and intracellular localization of MMP1, MMP2, MMP3, MMP7, and MMP9 in IPMN by immunohistochemistry. A total of 45 IPMN lesions (14 adenomas, 17 borderline lesions, nine noninvasive carcinomas, and five invasive lesions) from 21 patients were examined. MMP1, MMP2, MMP7, and MMP9 were expressed in tumor cells. Frequency of tumor cells expressing MMP7 was low in adenomas (median, 5.0%), higher in borderline lesions (median, 30.0%), in noninvasive carcinomas (median, 50.0%), and in invasive lesions (median, 80.0%), with a significant trend (P < 0.0001). Such a trend was also observed when the lesions were classified into gastric and intestinal subtypes (P < 0.0001 and P = 0.011, respectively). Basolateral expression of MMP7 in tumor cells was more prominent in lesions with higher histological grades (P < 0.0001). The frequency and the localization of MMP1, MMP2, and MMP9 did not correlate to the histological grades. MMP7 may contribute to the process by which IPMN advances from adenoma to carcinoma and to subsequent invasion of tumor cells in IPMN.