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Biomedical subjects

U Bleyl

Publications and source records attributed to U Bleyl.

At least 19 recordsLinked to original sources
PubMed2004

Spontaneous malignant transformation of conventional giant cell tumor.

Spontaneous malignant transformation of conventional giant cell tumor (GCT) of bone is exceedingly rare. We report on a case of GCT of the iliac crest in a 35-year-old woman with malignant change into a high-grade osteosarcoma 10 years after the first appearance of GCT on a radiograph. Since the patient refused therapy for personal reasons the tumor remained untreated until sarcomatous transformation occurred. Image cytometry showed DNA aneuploidy and a suspiciously high 2c deviation index (2cDI) in the primary bone lesion. A thorough review of the world literature revealed only seven fully documented cases of secondary malignant GCT which matched the definition of a "sarcomatous growth that occurs at the site of a previously documented benign giant cell tumor" and not treated by radiotherapy. These cases as well as the current one suggest that a spontaneous secondary malignant GCT presents as a frankly sarcomatous tumor in the form of an osteosarcoma or malignant fibrous histiocytoma. It usually appears at sites of typical GCTs-often without any recurrent intermediate state-and is diagnosed 3 or more years after the primary bone lesion. The prognosis is poor.

Adult↗
PubMed2002

c-MYC activation in primary and metastatic ductal adenocarcinoma of the pancreas: incidence, mechanisms, and clinical significance.

Amplification and overexpression of c-MYC is a common event in various neoplasias. Recently, comparative genomic hybridization (CGH) of primary pancreatic adenocarcinomas revealed a distinct high-level amplification of 8q23-qter, suggesting that c-MYC located on 8q24 may be a candidate oncogene. To evaluate the biological significance and prognostic value of c-MYC activation in pancreatic carcinoma, we performed interphase fluorescence in situ hybridization (FISH) and immunohistochemistry on a series of 69 primary pancreatic adenocarcinomas, 19 corresponding lymph node metastases, and 5 pancreatic intraductal lesions. Dual color FISH using a probe for c-MYC (8q24) and a centromeric probe for chromosome 8 revealed amplification of c-MYC in 32.3% and 29.4% of primary and metastatic tumors, respectively. Immunostaining identified c-MYC protein overexpression in 43.5% of primaries and 31.6% of metastases. Low concordance between positive FISH and immunostaining (13.4%) suggests multiple independent regulatory pathways of c-MYC activation. Statistical evaluation revealed significant correlation (alpha = 0.033) between c-MYC protein overexpression and histopathological tumor grade but absence of correlation with tumor stage or lymph node status. Analysis of pancreatic intraductal lesions showed c-MYC amplification and protein overexpression in two of five cases in which invasive carcinoma exhibited identical aberrations. We conclude that deregulation of c-MYC protein is common in pancreatic cancer and that it may be involved in early neoplastic development and progression rather than in locoregional spread of invasive cancer.

Adenocarcinoma↗
PubMed2002

Cutaneous large B-cell lymphoma of the leg masquerading as a chronic venous ulcer.

We report on a 74-year-old female patient with a primary cutaneous CD20+, diffuse large cell B-cell lymphoma of the lower leg resembling a chronic non-healing leg ulcer. There was no evidence of systemic involvement on computed tomography (CT) scans of the chest, abdomen and pelvis; a slightly enlarged lymph node in the right groin showed dermatopathic lymphadenopathy on histology and immunohistochemistry. Involvement of the bone marrow and peripheral blood was ruled out by punch biopsy and fluorescent activated cell sorter (FACS) analysis of the blood, respectively. Therapeutic anti-CD20 monoclonal antibody rituximab was given at 375 mg m(-2) i.v. once weekly for 7 weeks, without adverse effects, resulting in a minor improvement in the centre of the ulcerated tumour. Unfortunately, the response was not maintained, and after 7 weeks of treatment the patient started to develop new tumour lesions at the border of the ulcer. Local radiotherapy was started and combined photon and electron beam irradiation induced complete remission of the B-cell lymphoma.

Aged↗
PubMed2000

Identification of frequent chromosomal aberrations in ductal adenocarcinoma of the pancreas by comparative genomic hybridization (CGH).

Despite the continuous progress in molecular methodology, the genetic events involved in the initiation and progression of ductal adenocarcinoma of the pancreas remain largely unknown. In this study, 33 pancreatic ductal adenocarcinomas were screened for genomic alterations by comparative genomic hybridization (CGH). To date, most CGH studies of pancreatic cancer have been based on cell lines. To emphasize genetic imbalances that are involved in the in vivo development and progression of pancreatic carcinoma only fresh-frozen or paraffin-embedded tumour samples were analysed in the present study. Twenty-two tumours (67%) showed genomic alterations involving up to three (12%) or more (55%) chromosomal regions. The number and nature of the genetic imbalances did not, however, correlate with tumour stage or grade. Chromosome 18 was preferentially altered in the tumours analysed. Frequent chromosomal losses were found at 18q, 10q, 8p, and 13q. Commonly gained regions were located on 8q and 3q. Moreover, high copy number amplifications of the chromosomal regions 5p, 8q22-ter, 12p12-cen, 19q12-13.2, and 20q were identified. These data provide evidence for the occurrence of characteristic genomic alterations which are of biological relevance for the genesis of pancreatic cancer. The identified altered chromosomal regions may harbour tumour genes which involved in the multistep process of pancreatic carcinogenesis.

Adenocarcinoma↗
PubMed2000

Expression of MAGE antigens and analysis of the inflammatory T-cell infiltrate in human seminoma.

The MAGE gene family encodes antigens that are recognized by cytotoxic T-cells. The expression of MAGE antigens has been linked to tumor stage, and MAGE peptides are under investigation as possible vaccines. Seminomas are tumors that are typically accompanied by a heavy inflammatory infiltrate, but have not been studied with regard to their MAGE antigen expression and its correlation with the inflammatory infiltrate. We investigated, therefore, MAGE protein expression, the amount of cytotoxic T-cells, clonality of the lymphocytic infiltrate, apoptotic activity and occurrence of necrosis. Specimens of 27 patients with classical seminoma were examined by immunohistochemistry for CD4, CD8, CD56, CD45R0, beta2-microglobulin and HLA-DR. MAGE expression was detected with the monoclonal antibody 57B, reactive with MAGE-1, -3, -4, -6 and -12. Clonality of the inflammatory infiltrate was examined by multiplex polymerase chain reaction (PCR) analysis of the T-cell receptor rearrangement. Apoptotic cells were detected by DNA nick-end labeling of fragmented DNA, and the apoptotic index was determined semi-quantitatively. Expression of 57B was found in 19 (70%) of 27 seminomas. In all cases, more than 70% of T-cells expressed CD45R0. In four cases, a predominant infiltration of CD8-positive cytotoxic T-cells (CD4/CD8 ratio < 1) was present. However, 15 seminomas showed a CD4/CD8 ratio > 1. In all cases, infiltration of CD56-positive natural killer cells was only focal. HLA-DR expression was not detectable in tumor tissue; beta2-microglobulin was only focal in three cases. Analysis of the T-cell clonality revealed a polyclonal population. The apoptotic index was not significantly different in 57B-positive seminomas (4.15%) compared with 57B negative seminomas (3.80%). Also, no correlation between the 57B expression and the occurrence of necrosis was found. MAGE antigens are homogeneously expressed in most seminomas, but their presence does not appear to represent a dominant epitope responsible for the lymphocytic infiltrate.

Adult↗
PubMed2000

Correlation between neovascularisation and neuroendocrine differentiation in prostatic carcinoma.

Neuroendocrine (NE) differentiated tumor cells are found in almost all prostatic carcinomas. Prostatic carcinomas with a high NE differentiation have a poor prognosis and increased metastatic potential. A relationship between the neovascularisation density in the tumor and the metastatic potential in prostatic carcinoma is well known. NE cells and microvessels were demonstrated immunohistochemically on 102 radical prostatectomy specimens using antibodies against Chromogranin A and CD34. Standard areas (7.9 mm2) of maximal Chromogranin A expression and highest vascularisation were determined and topographically related by light microscopy. Area density of microvessels was evaluated morphometrically. NE tumor cells were present in all prostatic carcinomas studied. High grade prostatic carcinomas expressed significantly more NE tumor cells and exhibited a higher neovascularisation than low grade carcinomas. There was significantly higher neovascularisation in high grade tumors with many, as compared to high grade tumors with few, NE tumor cells. Poorer pathological staging correlated with increased neovascularisation and stronger NE differentiation. A topographical relationship between the area of maximal NE tumor cells and the area of highest neovascularisation was found in 80.4% of all cases. An analysis of variance revealed a large number of NE tumor cells as the only predictor of an increased neovascularisation (p = 0.0006). These observations support the concept that increased neovascularisation is influenced not only by poor pathological grading but also by a high NE differentiation.

Adenocarcinoma↗
PubMed2000

Polo-like kinase: a novel marker of proliferation: correlation with estrogen-receptor expression in human breast cancer.

Previous data have shown that the mRNA-expression of the serin/threonine-kinase polo-like kinase (PLK) is closely correlated with the survival of patients suffering from a subset of malignant tumors. PLK-mRNA and protein-expression are restricted to cells in the cell cycle. PLK-mRNA-transcripts are highly abundant in proliferating cells; no gene expression is found in G0-phase cells. Here we investigated the mRNA- and protein-expression of PLK- and estrogen-receptor (ER) in human breast-carcinoma by northern-blotting, RT-PCR and immunohistochemistry. The expression of MIB-I was determined on serial sections. Analysis of the immunohistochemical data revealed a close correlation between the ER and PLK-expression (r = 0.677; p = 0.001, n = 30). No relationship between the mRNA-expression of ER and PLK was found. Furthermore, no correlation for the protein expression of PLK and MIB-I exists. The influence of estrogen (ES) is known to have proliferative potential. The expression of ER correlates with the ES-plasma-level. In addition, the hormone cycle of premenopausal women undergoes rapid vacillations with varying effects on the proliferating tumor cells, e.g., growth induction. Our results therefore show that ER-expression is not only of therapeutic value for the clinician, but it may also be a tool for determining the tumor proliferation index more precisely by integrating the hormone-mediated proliferation stimulus.

Adult↗
PubMed2000

Validation of immunolocalization of the urokinase receptor expression in ductal carcinoma in situ of the breast: comparison with detection by non-isotopic in-situ hybridization.

AIMS: Ductal carcinoma in situ (DCIS) is a pre-invasive form of mammary carcinoma with no microscopic evidence of cancer cell invasion through the basement membrane. However, for initiation of invasion, tumour cells have to acquire and focus proteolytic activity on to the cell surface in order to infiltrate the surrounding extracellular matrix. The receptor (uPA-R or CD87) for the serine protease urokinase-type plasminogen activator (uPA) plays a central role in invasion and metastasis. This study was performed to determine and localize m-RNA and protein of uPA-R in ductal carcinoma in situ of the breast. METHODS AND RESULTS: We analysed uPA-R mRNA and protein expression by in-situ hybridization and immunohistochemistry, respectively, in 50 formalin-fixed, paraffin-embedded specimens of DCIS. Three different antibodies were used to stain cell-associated uPA-R; chicken polyclonal antibody (pAb) HU277 and monoclonal antibodies (mAb) IID7 and 3936. In all cases, myoepithelial and stromal cells reacted with either antibody. Especially, reaction of macrophage-like cells with mAb 3936 resulted in a well-marked and bright staining. Applying mAb IID7, in 46 of the 50 breast specimens tumour cells showed a positive immunoreaction. Likewise pAb HU277 stained tumour cells in 40 of the 50 cases, whereas mAb 3936 reacted with only 24 of the 50 tissue sections. Endothelial cells were marked by both mAb IID7 and pAb HU277 (46/50 and 35/50, respectively); mAb 3936 did not label at all. All of the cell types stained by mAb IID7 and pAb HU277 also displayed reactivity with uPA-R mRNA-specific antisense oligonucleotides in in-situ hybridization. CONCLUSIONS: Our results reveal the presence of the tumour invasion-related receptor for the protease uPA not only in invasive ductal breast carcinoma but also in different types of DCIS.

Adult↗
PubMed1999

Urokinase plasminogen activator receptor (CD87) expression of tumor-associated macrophages in ductal carcinoma in situ, breast cancer, and resident macrophages of normal breast tissue.

UNLABELLED: Macrophages concentrate urokinase-type plasminogen activator (uPA) at the cell surface by expressing urokinase receptors (uPAR) in order to focus the pericellular space plasminogen-dependent proteolysis important in matrix remodeling and cell movement. This study examines the uPAR levels of tumor-associated macrophages (TAM) of invasive breast carcinomas, of TAMs from ductal carcinoma in situ (DCIS) and of macrophages derived from normal (non-tumor) breast tissue. TAMs from invasive breast carcinomas (n = 30), from DCIS (n = 12), and macrophages from normal breast tissue (n = 30) were cultured and immunocytochemically phenotyped by using a panel of antibodies. Urokinase receptor levels were determined by Western blot analysis and in cell-free supernatants by enzyme-linked immunosorbent assay. Urokinase receptor cell surface fluorescence intensity was determined by FACS and by confocal laser scan microscopy. Urokinase-receptor mRNA was detected by in situ hybridization. TAMs of invasive breast carcinomas and of DCIS possess significantly elevated uPAR levels compared with macrophages derived from normal breast tissue. CONCLUSIONS: activated macrophages with elevated uPAR levels belong to inflammatory areas in close vicinity of infiltrating and non-infiltrating (DCIS) tumor cells. Blood monocytes that possess elevated uPAR-levels may be selectively recruited from the bloodstream to inflammatory sites close to carcinoma cells, and/or breast cancer and precursor lesions may induce elevated uPAR-levels in TAMs by paracrine interactions.

Breast Neoplasms↗
PubMed1999

Immunolocalization of beta catenin in intestinal polyps of Peutz-Jeghers and juvenile polyposis syndromes.

AIM: To examine the membranous and nuclear distribution of beta catenin in the epithelial cells of gut polyps from Peutz-Jeghers syndrome and juvenile polyposis in comparison with other types of polyps and tumours. METHODS: Immunohistochemistry for beta catenin and proliferation markers was performed on conventional paraffin sections. Immunohistological staining was carried out on Peutz-Jeghers syndrome polyps from four different families, on juvenile polyposis polyps from two different families, on solitary juvenile polyps, and on hyperplastic polyps. The immunohistochemistry was evaluated qualitatively in relation to defined areas of the polyps. RESULTS: All polyps from the hamartomatous polyposis syndromes (Peutz-Jeghers syndrome and juvenile polyposis) showed nuclear localization of beta catenin in some epithelial cell nuclei. In Peutz-Jeghers syndrome polyps beta catenin positive nuclei were seen at the base of the deep crypt infoldings. In juvenile polyposis polyps and in some solitary juvenile polyps they were found in irregularly distributed cryptal epithelial cells corresponding to the proliferative compartments. Normal mucosa of the gut and hyperplastic polyps of the colon do not show nuclear staining for beta catenin. CONCLUSIONS: The dysregulation of cellular beta catenin distribution is not only a phenomenon of adenoma formation and adenoma progression in the colon--it is at least focally present in polyps of the hamartomatous type and is related to the proliferation zones of these polyps. The nuclear translocation of beta catenin most probably reflects a disturbed beta catenin metabolism. In view of the different functions of beta catenin during development and cell differentiation, the nuclear translocation of beta catenin is likely to be an important factor in enhanced cell proliferation which escapes local control mechanisms.

Adenocarcinoma↗
PubMed1997

Expression of tenascin in lymphocytic autoimmune thyroiditis.

AIMS: To study the distribution of tenascin by immunocytochemistry in autoimmune diseases of the thyroid. METHODS: Thyroids from patients with inflammatory lesions of the thyroid (lymphocytic thyroiditis Hashimoto, Grave's disease, thyroiditis DeQuervain) were studied by immunocytochemistry using antibodies against tenascin, collagen III, and collagen IV. RESULTS: In autoimmune lymphocytic thyroiditis Hashimoto there was a characteristic corona-like staining pattern of tenascin around all activated lymph follicles with germinal centres. This staining pattern contrasted with the immunoreactions for collagen III and IV, which were not enhanced in the perilymphofollicular interstitium. In cases of thyroiditis DeQuervain the areas of early and ongoing fibrosis showed some diffuse staining for tenascin and for collagen III. Enhanced diffuse immunostaining for collagen IV in the perivascular and interfollicular interstitium was present in cases of Grave's disease. In Grave's disease no characteristic immunoreaction was detectable for tenascin. CONCLUSIONS: The corona-like expression of tenascin around lymphofollicular infiltrates is distinctive of cases of lymphocytic thyroiditis. A similar staining pattern for tenascin has been reported in lymphoid hyperplasia of the thymus associated with myasthenia gravis, another autoimmunological disorder. There are good arguments that the activation and infiltration of lymph follicles in the thyroid during the course of autoimmune diseases lead to stimulation and activation of the surrounding mesenchyme producing tenascin as part of the extracellular matrix.

Biomarkers↗