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991.
The urokinase-type plasminogen activator (uPA) system plays a central role in extracellular matrix degradation, cell migration, and invasion. uPA belongs to the family of serine proteases. It has been shown that its proteolytic activity is involved in the metastatic process by activation and binding to its receptor (uPAR). Previous studies in several organ systems have elucidated a higher uPA expression in malignant tissue in comparison to normal tissue. In this study uPA and uPAR gene expression were investigated in 18 human renal cell carcinoma (RCC) specimens in comparison with adjacent non-malignant renal tissues. mRNA in situ hybridisation and immunohistochemical staining were performed. mRNA of uPA and uPAR was significantly higher expressed in 56% (10/18) and 72% (13/18) of the RCC specimens in comparison to the adjacent non-malignant renal tissue (p<0.0001), respectively. uPA-mRNA and uPAR-mRNA were expressed predominantly in malignant renal cells and in very few surrounding stromal cells. The elevated expression of uPAR-protein in RCC reached statistical significance compared to adjacent normal tissue (p=0.007). uPAR genes were higher expressed in comparison to uPA alone. There was a statistical trend that higher expression of uPA and uPAR corresponded with TNM tumour stage and grade in RCC. Further investigations need to be done with larger sample sizes to prove a correlation of expression between uPA and uPAR to a more aggressive phenotype. We conclude that uPA- and uPAR are overexpressed in RCC and could function as tumour markers.  相似文献   
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Schwannoma is a benign, encapsulated tumor that is derived from Schwann cells. Approximately 25% to 45% of schwannomas occur in the head and neck. The most common site is the parapharyngeal space of the neck; intrapharyngeal occurrence is extremely rare. To our knowledge, this is the first report of a pedunculated schwannoma in the supraglottic oropharynx. Because of the location and mass of the tumor, the main symptom was dysphagia. The tumor was excised via direct microlaryngoscopy, and no recurrence was seen after 2 years of follow-up. When schwannomas are located in the pharynx, they may cause dyspnea and dysphagia or impair phonation. Therefore, when dysphagia is present, a thorough diagnostic procedure should be performed to evaluate the morphology and function of the upper aerodigestive tract.  相似文献   
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BACKGROUND: Radiotherapy is potentially curative in early stages of follicle center lymphoma. Frequent side effects are pancytopenia, nausea and abdominal discomfort. A radiation-induced liver injury with serious clinical symptoms and changes in liver function is a rare complication. CASE REPORT: Whole abdomen was irradiated in a 49-year-old patient with a centrocytic-centroblastic lymphoma, stage IA (localization: left inguinal region). A total dose of 30 Gy was delivered in a weekly fractionation of five times 1.5 Gy. Kidneys were protected by shielding after a dose of 13.5 Gy, liver blocks were positioned after 25 Gy. During the last 2 days of therapy the patient presented with weight gain, ascites, dyspnoea and elevated liver enzymes. Diagnostics revealed hepatosplenomegaly, ascites and an increased portosystemic pressure gradient. Liver biopsy specimen showed a veno-occlusive disease. Complete relief of symptomatology was achieved within 7 days following placement of a transjugular intrahepatic portosystemic stent-shunt (TIPSS), heparinization and diuretics. Liver enzymes are in the normal range. CONCLUSION: Veno-occlusive disease of the liver (VOD) is a very rare side effect of primary abdominal irradiation of follicle center lymphoma. This complication should be taken into consideration if a patient presents with upper right quadrant pain, ascites and elevation of liver enzymes especially within 4 months following radiotherapy. Genesis of veno-occlusive disease, diagnostics, therapy and a review of the literature are presented.  相似文献   
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Nemaline myopathies are a clinically and genetically heterogeneous group of congenital myopathies, mainly characterized by muscle weakness, hypotonia and respiratory insufficiency. Here, we report a male foetus of consanguineous parents with a severe congenital syndrome characterized by arthrogryposis detected at 13 weeks of gestation. We describe severe complex dysmorphic facial and musculoskeletal features by post mortem fetal examination confirming the prenatal diagnosis. Histomorphological and ultrastructural studies of skeletal muscle reveal mini-rods in myotubes caused by a novel homozygous splice-site mutation in NEB (NM_001164508, chr2:g.152,417,623C>A GRCh37.p11 | c.19,102–1G>T ENST00000397345.3). No rods were seen in the myocardium. We discuss the relevance of this mutation in the context of nemaline myopathies associated with early developmental musculoskeletal disorders.  相似文献   
996.
Patients with BRAFV600E/K-driven melanoma respond to the BRAF inhibitor vemurafenib due to subsequent deactivation of the proliferative RAS/RAF/MEK/ERK pathway. In BRAF WT cells and those with mutations that activate or result in high levels of the BRAF activator RAS, BRAF inhibition can lead to ERK activation, resulting in tumorigenic transformation. We describe a patient with malignant melanoma who developed chronic lymphocytic leukemia (CLL) in the absence of RAS mutations during vemurafenib treatment. BRAF inhibition promoted patient CLL proliferation in culture and in murine xenografts and activated MEK/ERK in primary CLL cells from additional patients. BRAF inhibitor–driven ERK activity and CLL proliferation required B cell antigen receptor (BCR) activation, as inhibition of the BCR-proximal spleen tyrosine kinase (SYK) reversed ERK hyperactivation and proliferation of CLL cells from multiple patients, while inhibition of the BCR-distal Bruton tyrosine kinase had no effect. Additionally, the RAS-GTP/RAS ratio in primary CLL cells exposed to vemurafenib was reduced upon SYK inhibition. BRAF inhibition increased mortality and CLL expansion in mice harboring CLL xenografts; however, SYK or MEK inhibition prevented CLL proliferation and increased animal survival. Together, these results suggest that BRAF inhibitors promote B cell malignancies in the absence of obvious mutations in RAS or other receptor tyrosine kinases and provide a rationale for combined BRAF/MEK or BRAF/SYK inhibition.  相似文献   
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Clinical & Experimental Metastasis - Approximately 90% of cancer-related deaths result from cancer metastasis. In prostate and breast cancers, bone is the most common site of cancer cell...  相似文献   
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