Malignant extrarenal rhabdoid tumour (MERT) with liver metastases as a rare cause of an esophageal tumor in a 57 years old patient.

Tumors with a rhabdoid phenotype are aggressive neoplasms with a dismal prognosis. Malignant extrarenal rhabdoid tumor (MERT) of the esophagus is an extremely rare disease with so far only 6 cases reported. We report on a 57-year-old male patient with rhabdoid tumor situated in the esophagus with metastases to the liver and local lymph nodes. Assuming an undifferentiated esophageal adenocarcinoma a palliative chemotherapy with 5-FU/folinic acid, oxaliplatin, and docetaxel (FLOT) was initiated which was changed towards a combination of doxorubicin and ifosphamide as immunohistochemistry of the primary and the liver metastases revealed a rhabdoid tumor. This treatment with doxorubicin and ifosphamide resulted in a short clinical and radiological response which lasted only for 2 months. Due to the bad general condition at the time of progression no further chemotherapy was initiated. The patient died due to tumor progression 6 months after initial diagnosis which is consistent with other reports on malignant extrarenal rhabdoid tumors (median survival of metastatic disease less than 6 months). Thus, metastatic MERT represents a disease with a poor prognosis and no established standard therapy.

TGF-beta-induced invasiveness of pancreatic cancer cells is mediated by matrix metalloproteinase-2 and the urokinase plasminogen activator system.

TGF-beta strongly promotes local tumor progression in advanced epithelial tumors, though the underlying mechanisms are poorly understood. In the present study, we demonstrate the potential of TGF-beta to increase the invasiveness of the pancreatic cancer cell lines PANC-1 and IMIM-PC1. TGF-beta-induced tumor cell invasion occurred in a time-dependent manner, started after 12 hr and continued to increase even 48 hr after a single application of the growth factor. Blocking of secreted TGF-beta1 by application of neutralizing antibodies 24 hr after TGF-beta treatment completely prevented the sustained effects of TGF-beta on tumor cell invasion. Together with our previous observation that TGF-beta1 up-regulates its own expression in both cell lines, our data suggest that TGF-beta1 acts in an autocrine manner to maintain tumor cell invasion. As measured by Northern blot hybridization and zymography, TGF-beta treatment of PANC-1 and IMIM-PC1 cells resulted in strong up-regulation of expression and activity of both matrix metalloproteinase-2 (MMP-2) and the urokinase plasminogen activator (uPA) system. Treatment with MMP inhibitors or inhibitors of the uPA system caused significant reduction of TGF-beta-induced invasiveness in both cell lines. In contrast, expression and activity of MMP-2 and uPA as well as tumor cell invasiveness remained unaffected in cell lines with defects of the TGF-beta type II receptor (MiaPaca2) or the Smad4 gene (IMIM-PC2 and CAPAN-1). In these cell lines, TGF-beta also failed to auto-induce its own expression. In conclusion, our results suggest that TGF-beta1 is a strong promotor of pancreatic cancer progression. TGF-beta thereby acts in an autocrine manner to induce tumor cell invasion, which is mediated by MMP-2 and the uPA system.

Transforming growth factor beta1 treatment leads to an epithelial-mesenchymal transdifferentiation of pancreatic cancer cells requiring extracellular signal-regulated kinase 2 activation.

The aim of this study was to examine the effects of transforming growth factor (TGF) beta1 on the phenotype and the biological behavior of pancreatic cancer cell lines with and without mutations in the TGF-beta signaling pathway and to elucidate whether the Ras signaling cascade participates in mediating these effects of TGF-beta1. TGF-beta-responsive (PANC-1, COLO-357, and IMIM-PC1) and nonresponsive (CAPAN1 and IMIM-PC2) pancreatic cancer cell lines with activating mutations of the Ki-Ras oncogene were treated with 10 ng/ml TGF-beta1 over time. Phenotypic alterations were studied by electron and phase contrast microscopy and by immunohistochemistry and expression analyses of differentiation markers. The influence of TGF-beta on tumor cell scattering, migration, and invasion was determined. The role of the Ras-mitogen-activated protein kinase kinase (MEK)-extracellular signal-regulated kinase (ERK) cascade in mediating TGF-beta-induced morphological and functional effects were studied by pretreatment with the MEK1 inhibitor PD 98059 and by measuring ERK2 activation using immune complex kinase assays. TGF-beta1 led to a reversible and time-dependent epithelial-mesenchymal transdifferentiation (EMT) in TGF-beta-responsive pancreatic cancer cell lines, characterized by a fibroblastoid morphology and an up-regulation of mesenchymal markers and a down-regulation of epithelial markers. EMT was associated with an increase in tumor cell migration, invasion, and scattering. In the responsive cell lines, TGF-beta1 induced a moderate but sustained activation of ERK2. EMT, the concomitant changes in gene expression, and the invasive and migratory potential were reduced or abolished by pretreatment with the selective MEK1 inhibitor. Thus, in TGF-beta-responsive pancreatic cancer cells with activating Ki-Ras mutations, TGF-beta1 treatment caused an EMT associated with a more invasive phenotype. Cross-talk with the Ras-MEK-ERK-signaling cascade appears to be essential for mediating these effects of TGF-beta1.

Pancreatic function tests: when to choose, what to use.

Although techniques for high-resolution imaging of the pancreas are constantly being improved, the evaluation of pancreatic function remains crucial for the workup of pancreatic diseases. More than 20 direct and indirect tests are available for the assessment of pancreatic function. Measurement of fecal elastase-1 is recommended as the most suitable test for the initial assessment of pancreatic function. Among other techniques, the pancreolauryl test, and alternatively the BT-PABA (N-benzoyl-L-tyrosyl-p-aminobenzoic acid) or the (13)C-mixed-triglyceride test, yield the best sensitivity and specificity. Nevertheless, all indirect tests are of limited value in patients with mild to moderate impairment of pancreatic function. In these patients, the secretin-caerulein test remains the gold standard.

Loss of the Y chromosome is a frequent chromosomal imbalance in pancreatic cancer and allows differentiation to chronic pancreatitis.

In a study for the identification of genomic alterations in pancreatic cancer, representational difference analysis was used and led to the isolation of 2 distinct fragments, deleted on the Y chromosome in the xenografted tumor DNA of a male patient with an adenocarcinoma of the pancreas. Loss of Y chromosomal material was further studied in 11 pancreatic cancer cell lines of male origin, using PCR amplification of 5 sequence tagged sites (STSs) distributed along the Y chromosome; 8/11 cell lines exhibited a complete loss of the Y chromosome and 3 had deletions. To examine the status of the Y chromosome in situ, interphase FISH analysis was performed on paraffin sections from pancreatic carcinoma (n=7) and chronic pancreatitis (n=7) tissues, and the loss of Y-chromosomal STS-markers was studied in 6 xenograft tumors obtained from male pancreatic cancer patients. This analysis revealed that a loss of the Y chromosome occurs in vivo in primary pancreatic tumor cells, whereas the Y chromosome was intact in chronic pancreatitis. Our data suggest that loss of Y is a frequent event occurring in male pancreatic tumors. Although there is no evidence for a functional implication of Y chromosome loss, it effectively differentiates between a malignant and a benign condition as e.g. chronic pancreatitis. Thus, this genetic alteration may be of diagnostic use.

Use of DNA arrays/microarrays in pancreatic research.

In recent years, enormous technical advances in experimental protocols as well as robotic and bioinformatic techniques have allowed DNA array/microarray technology to emerge as the leading technology in the field of functional, disease-related genome analysis. Multiple applications exist for DNA arrays/microarrays including comparative genomic analysis to identify chromosomal imbalances (Matrix-CGH), the study of mutations and genetic polymorphisms, and the study of gene expression (expression profiling). Expression profiling is the most widely used application of DNA array/microarray technology and allows to measure gene expression of thousands of genes simultaneously. The present review describes the basic principles of expression profiling analyses and outlines some applications in pancreatic cancer research.

Role of MT-MMPs and MMP-2 in pancreatic cancer progression.

Activation of matrix metalloproteinase-2 (MMP-2) by the membrane-type matrix metalloproteinases (MT-MMPs) has been associated with tumor progression. In the present study, we examined the role of MMP-2 and its activators MT1-MMP, MT2-MMP and MT3-MMP in pancreatic tumor cell invasion and the development of the desmoplastic reaction characteristic of pancreatic cancer tissues. Northern blot analyses revealed that transcript levels of MT1-MMP and MT2-MMP, but not MT3-MMP, were enhanced in pancreatic cancer tissues (n = 18) compared with both chronic pancreatitis (n = 9) and healthy pancreas (n = 9). A good correlation was found between MT1-MMP and both MMP-2 expression (p < 0.01) and activity in pancreatic cancer tissues. In addition, expression and activation of MMP-2 were strongly associated with the extent of the desmoplastic reaction in pancreatic cancer tissues. Invasion assays showed a good correlation between MMP-2 expression and activity and the invasive potential of pancreatic cancer cell lines. In cell lines with high levels of MMP-2 expression and activity, the MMP inhibitor Batimastat led to significant reduction of the number of invading cells. Our results suggest that MT1-MMP is involved in the progression of pancreatic cancer via activation of MMP-2. MMP-2 itself plays an important role in tumor cell invasion and appears to be associated with the development of the characteristic desmoplastic reaction in pancreatic cancer.

Prospective evaluation of brush cytology of biliary strictures during endoscopic retrograde cholangiopancreatography.

BACKGROUND AND STUDY AIMS: Cytological methods may be used to differentiate benign from malignant biliary strictures. We evaluated the diagnostic accuracy of an endobiliary cytotechnique which can easily be performed during endoscopic retrograde cholangiopancreatography. PATIENTS AND METHODS: Cytological samples were obtained by brushing biliary strictures via a guide wire in 86 patients with strictures of unknown status. Samples were classified by an expert cytologist as normal (including reactive cells), severely dysplastic (atypical cells suspicious of malignancy) and clearly malignant. A final diagnosis was achieved in 78 patients based on intraoperative findings and histological investigation, autopsy or prolonged follow-up. Strictures were malignant in 57 cases (31 pancreatic carcinoma, 20 cholangiocarcinoma, 6 others) and benign in 21 cases (11 chronic pancreatitis, 5 chronic nonspecific inflammation, 5 others). RESULTS: The overall results for brush cytological investigation were sensitivity 56.1%, specificity 90.5%, positive predictive value 94.1%, negative predictive value 43.2 %, and accuracy 65.4 %. Sensitivity was significantly higher (P<0.005) in cholangiocarcinoma (80%) compared with pancreatic carcinoma (35.5%). The overall specificity of less than 100 % resulted from dysplasia in two patients with chronic pancreatitis and inflammatory mass. No procedure-related complications occurred. CONCLUSIONS: Brush cytology is helpful for differentiating between benign and malignant biliary strictures, especially in suspected cholangiocarcinoma. Dysplastic cells may occur in the absence of malignancy and their presence should therefore be interpreted cautiously.

Prevalence of resistance to clarithromycin and its clinical impact on the efficacy of Helicobacter pylori eradication.

BACKGROUND: Triple therapy with a proton-pump inhibitor (PPI) in combination with metronidazole and clarithromycin is the method of choice for eradication of Helicobacter pylori. Failures have been primarily blamed on the development of resistance to clarithromycin. The present study investigated the prevalence and clinical significance of resistance to clarithromycin and metronidazole in determining therapeutic success of both triple therapy as a primary eradication method and high-dose dual therapy in non-responders. METHODS: On the basis of prior therapy, H. pylori-positive patients were assigned to one of two groups in the present prospective study. Group A (n = 93) included patients who had not undergone any prior eradication treatment, whereas group B (n = 15) consisted of patients who had received clarithromycin but in whom eradication had been unsuccessful. All patients underwent endoscopy with biopsy for bacterial culture and resistance studies. Patients in group A were treated with a 7-day regimen of pantoprazole (40 mg twice daily), metronidazole (500 mg twice daily), and clarithromycin (250 mg twice daily), whereas those in group B received omeprazole (40 mg three times a day) and amoxycillin (1000 mg three times a day ) for 14 days. Success of the eradication treatment was ascertained by means of the 13C urea breath test. RESULTS: In group A resistance to clarithromycin and metronidazole was identified in 3 patients (4.9%) and in 14 patients (22.9%), respectively. Eradication proved successful in 78 of 84 patients (92.6%) followed up. Two of the 3 patients with primary clarithromycin resistance and 1 of the 14 patients with metronidazole resistance did not respond to treatment. In group B isolated or combined resistance to clarithromycin was found in seven patients, whereas another four showed isolated resistance to metronidazole. Eradication proved successful in 10 of 13 controlled patients (76.9%) followed up, and only 2 patients reported severe side effects. CONCLUSION: Determination of antibiotic resistance before initiating therapy is not necessary, since primary resistance to clarithromycin is rare. The Italian triple therapy remains a highly effective primary therapeutic method. Further, routine determination of resistance in non-responders also seems to be superfluous because high-dose dual therapy is an effective and well-tolerated second-line therapy regardless of the patients' resistance status.

Laryngoplasty with vascularized and non-vascularized auricular mucochondral grafts. An experimental study in rabbits.

A composite graft from the rabbit ear, consisting of cartilage, perichondrium and oral mucosa, was transposed to reconstruct a defect in the thyroid cartilage of the larynx in 10 rabbits. Five grafts were transposed as an island on an intact neurovascular pedicle; the other 5 were performed as a free graft without vascularization. After 9 weeks all the rabbits with a vascularized cartilaginous graft survived, with no sign of respiratory distress. The internal lining of the newly formed larynx was composed of undifferentiated stratified squamous cell epithelium. The survival of an intact cartilage and mucosa prevented a serious scar reaction in the neo-larynx and maintained the patency of the restored lumen. In the rabbits with non-vascularized cartilaginous grafts, there was necrosis present within the mucosal grafts, with intensive formation of granulation tissue in the transplanted region and retraction of the lumen. The present study highlights the importance of using well-vascularized composite cartilaginous grafts in laryngeal reconstruction. The possibility of utilizing a vascularized cartilaginous graft in man is discussed.

Retrieval processes in recognition.

Retrieval processes in the long-term recognition of well organized material showed the expected organizational effects on "slow" recognition responses. Ss sorted 100 words into two to seven categories until a stable organization was achieved. The data showed the usual correlations between organization (number of categories used) and recall and recognition. Recognition tests a week after the sorting task revealed no differences between Ss using many or few categories for the "fast" recognition responses, defined as the faster 50% of each S's latency distribution. The organizational effect was clearly evident for the "slow" 50% of the responses. The data support the retrieval check hypothesis in recognition under the assumption that retrieval operations take additional time during the recognition process.