[Fever, atrial fibrillation, and angina pectoris in a 58-year-old man]. / Fieber, Vorhofflimmern und Angina pectoris bei einem 58-jährigen Patienten.

Primary cardiac lymphoma (PCL) respresents a very rare type of cardiac tumour. This report illustrates a case of PCL in an immunocompetent 58-year-old man presenting with atrial fibrillation and febrile syndrome. Comprehensive imaging [computer tomography (CT), cardiac magnetic resonance imaging (cMRI), 3-dimensional transesophageal echocardiography (3D-TEE)] identified a large right atrial tumour, leading to pericardial effusion. Isolated cardiac involvement was confirmed by positron emission tomography (PET)-CT. A diffuse large B-cell lymphoma (DLBCL) was diagnosed based on the results of a TEE-guided biopsy. A normalized PET scan (PETAL study) indicated complete remission following R-CHOP 14 immunochemotherapy. Thus, an interdisciplinary and multimodal approach avoided unnecessary cardiac surgery.

Analysis of growth factor-dependent signalling in human epithelioid sarcoma cell lines. clues To the role of autocrine, juxtacrine and paracrine interactions in epithelioid sarcoma.

Human epithelioid sarcoma (ES) is an extremely aggressive soft tissue tumour of unknown histogenesis. Although growth factor-dependent signalling cascades significantly affect the biological behaviour of malignant tumours, little is known so far about their role in human ES. The present investigation, therefore, analyses the coexpression and function of different growth factors and their receptors in the human ES cell line GRU-1 and its clonal subpopulations (GRU-1A, GRU-1B and GRU-1C). As shown by Northern blot, flow cytometry, immunocytochemistry and MTT assay, all ES cell lines expressed transforming growth factor (TGF)-alpha and the epidermal growth factor receptor (EGF-R). Although no response to exogenous TGF-alpha was observed, antagonistic anti-EGF-R antibodies (at 20 microg/ml) induced significant (P<0.05) growth inhibition in all cell lines. All cell lines showed coexpression of platelet-derived growth factor (PDGF)-A and the corresponding receptors. Neutralisation of ES-derived PDGF by anti-hPDGF antibodies resulted in significant (P<0.05) growth inhibition of all clonal subpopulations. Although all cell lines expressed TGF-beta(1) as well as TGF-beta type I and type II receptors (TGF-BI-R and TGF-BII-R), growth inhibition (P<0.05) by exogenous TGF-beta(1) was achieved in the clonal subpopulations only and not in the parental cell line. No ES cell line expressed acidic fibroblast growth factor (FGF) but stimulation of FGF type 3 and type 4 receptors (FGF-3R and FGF-4R) by exogenous acidic FGF (aFGF) resulted in a marked (P<0.05) acceleration of proliferation in all cell lines. In conclusion, our investigation suggests an intricate network of autocrine, juxtacrine and paracrine signalling between ES tumour cells and adjacent non-neoplastic stromal cells.

Functional intactness of stimulatory and inhibitory autocrine loops in human renal carcinoma cell lines of the clear cell type.

PURPOSE: The aim of the present study was to analyze the contribution of different stimulatory and inhibitory growth factors to the deregulated proliferation of human RCCs. MATERIALS AND METHODS: The expression of different growth factors and their corresponding receptors were analyzed by Northern blot, FACS, ELISA and immunocytochemistry in 13 permanent human RCC cell lines of the clear cell type. Moreover, the functional intactness of growth factor-related signal transduction pathways was investigated. RESULTS: All RCC cell lines expressed EGF-receptor mRNA and protein and 10 cell lines secreted TGF-alpha. Exogeneously added TGF-alpha resulted in a significant (p < 0.05) stimulation of growth in 6 RCC cell lines and a significant (p < 0.05) inhibition of proliferation in 3 cell lines. PDGF B and the corresponding type beta receptor were expressed in a single cell line. mRNA expression of PDGF A and PDGF-alpha-receptor as well as IGF-1 and its receptor could not be detected in any cell line. Eleven RCC cell lines expressed TGF-beta 1 mRNA and in all cell lines TGF-beta 1 secretion into the supernatant could be demonstrated. Whereas all cell lines exhibited TGF-beta type II-receptor mRNA, type I-receptor mRNA could be detected only in 3 cell lines. TGF-beta type III-receptor was observed in 1 cell line. Exogeneously added TGF-beta1 resulted in a significant (p < 0.05) inhibition of proliferation in 7 RCC cell lines. CONCLUSION: Clear cell RCCs exhibit a complex and heterogeneous expression pattern for various growth factors and their receptors. Growth factor secretion and intact signal transduction pathways in most clear cell RCCs facilitate an intricate modulation of RCC growth by autocrine and paracrine interactions between tumor cells and host tissue.

Acquisition of TGF-beta 1 resistance: an important progression factor in human renal cell carcinoma.

The balance of growth regulation in tumors can be profoundly disturbed by defects in the transforming growth factor-beta 1 (TGF-beta 1) system. Thus far, investigations into the secretion of TGF-beta 1, the expression of its type I, II, and III receptors, as well as the functional intactness of the TGF-beta 1 signal transduction pathways in human renal cell carcinomas (RCC) have been lacking. The objective of the present study, therefore, was to elucidate the role of the TGF-beta 1 system in RCC. We were able to determine the status of this system in 20 primary RCC and in 30 newly established human RCC cell lines of all major histologic types. All primary RCC showed expression of TGF-beta 1 and its type I and II receptors by immunohistochemistry, irrespective of histologic type. In vitro, all RCC cell lines secreted TGF-beta 1 protein as a biologically inactive complex, which cannot interact with cell-surface receptors. Type I ALK-5-receptor mRNA and protein were detected in 29 RCC cell lines, whereas type I ALK-2-receptor mRNA was found in all cell lines. Type II-receptor mRNA and protein could be demonstrated in all cell lines analyzed, and type III-receptor mRNA was observed in five RCC cell lines. Exogenously added, biologically active TGF-beta 1 (1 ng/ml) resulted in significant (p < 0.05) inhibition of proliferation in 14 of 30 RCC cell lines. Sixteen of thirty RCC cell lines, however, proved to be TGF-beta 1-resistant. This resistance could not be explained by mutations in two "hot spot" regions of the type II-receptor gene (bp 622 to 795 and bp 1868 to 2019), as was demonstrated by DNA sequencing in the TGF-beta 1-resistant RCC cell lines. In conclusion, our observations are the first to provide evidence of an "escape" from the negative growth control of TGF-beta 1 by a significant proportion of RCC, suggesting that the acquisition of TGF-beta 1 resistance is an important progression factor for human RCC.