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H Friess

Publications and source records attributed to H Friess.

At least 127 records · Page 7Linked to original sources
PubMed2000

Syndecan-1 expression is up-regulated in pancreatic but not in other gastrointestinal cancers.

Syndecan-1 belongs to the syndecan family of cell surface transmembrane heparan-sulfate proteoglycans, which participate in cell proliferation, cell migration and cell-matrix interactions. Decreased expression of syndecan-1 has been observed in some gastrointestinal malignancies, and it is thought that high levels of syndecan-1 correlate with the maintenance of epithelial morphology and inhibition of invasiveness. In our study, we characterized the expression of syndecan-1 in normal, chronic pancreatitis and primary and metastatic human pancreatic cancer tissues, in cultured pancreatic cancer cell lines and in esophageal, gastric, colon, and liver cancers. Pancreatic cancer cell lines expressed syndecan-1 mRNA and protein at variable levels. In addition, these cells also released syndecan-1 into the culture medium. Pancreatic cancer tissues markedly over-expressed syndecan-1 mRNA in comparison with both chronic pancreatitis (2.4-fold increase, p < 0.01) and normal pancreatic samples (10.6-fold increase, p < 0.01). There was no difference in syndecan-1 mRNA expression between early and advanced tumors. By in situ hybridization and immunohistochemistry, syndecan-1 expression was evident at relatively low levels in the ductal cells and less frequently in acinar cells of the normal pancreas. In chronic pancreatitis, syndecan-1 was present at low to moderate levels in areas with atrophic acinar cells and ductular complexes. In contrast, in pancreatic cancer tissues, syndecan-1 was present at moderate to high levels in the majority of the cancer cells within the tumor mass and also in metastatic lesions of pancreatic tumors. Syndecan-1 mRNA levels in other gastrointestinal malignancies (esophageal, gastric, colon and liver cancers) were not significantly different from the levels observed in the corresponding normal samples. Together, our findings suggest that syndecan-1 expression by pancreatic cancer cells may be of importance in the pathobiology of this disorder and that its role in pancreatic cancer seems to be different from that in other gastrointestinal malignancies.

Adenocarcinoma↗
PubMed2000

Epiregulin is Up-regulated in pancreatic cancer and stimulates pancreatic cancer cell growth.

Epiregulin belongs to the epidermal growth factor (EGF) family of polypeptides. Previous studies have underscored the important role of the EGF family of ligands and receptors in the pathology of pancreatic ductal adenocarcinoma (PDAC) and chronic pancreatitis (CP). It is not known, however, whether epiregulin may also have a role in these diseases. Therefore, in the present study we investigated the expression and function of epiregulin in five pancreatic cancer cell lines and in PDAC and CP tissue samples. Epiregulin mRNA was present at high (MIA-PaCa-2 cells) or moderate levels (ASPC-1, CAPAN-1, and T3M4) in most cells, but was below detection levels in PANC-1 cells. All the cell lines exhibited a dose-dependent increase in growth in response to recombinant human epiregulin. Epiregulin mRNA levels were increased 2.1-fold in PDAC samples (P < 0.01) and 1.7-fold in CP samples (P < 0.01), when compared with the normal controls. There was no correlation between epiregulin mRNA levels and tumor stage or grade. By in situ hybridization, a moderate to intense epiregulin mRNA signal was present in most pancreatic cancer cells in PDAC. In contrast, only a weak (normal pancreas) to moderate (CP) signals were present in the ductal and acinar cells in CP. These findings suggest that epiregulin may contribute to the pathobiology of PDAC, and may also have a role in CP.

Adenocarcinoma↗
PubMed2000

Enhanced expression of Silencer of death domains (SODD/BAG-4) in pancreatic cancer.

Pancreatic cancers are resistant to TNF-alpha-mediated apoptosis. Silencer of death domains (SODD) binds to TNF-alpha receptor TNFR-1, and prevents spontaneous self-association of death domains and inappropriate receptor signaling. In addition, overexpression of SODD suppresses TNF-alpha-induced cell death. In this report, we demonstrate increased SODD mRNA levels in pancreatic cancer (n = 30) in comparison to normal control tissues (n = 20, P < 0.01). In situ hybridization analysis revealed SODD expression predominantly in the cancer cells within the pancreatic tumor mass. In contrast, SODD mRNA levels were not different (P > 0.05) in four other gastrointestinal cancers (liver, esophagus, stomach, colon) compared with the corresponding normal tissues. These findings indicate that in contrast to other gastrointestinal malignancies, in pancreatic cancer SODD might block TNF-alpha-mediated apoptosis which may influence the growth of pancreatic cancer cells.

Adaptor Proteins, Signal Transducing↗
PubMed2000

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.

Adenocarcinoma↗
PubMed2000

Duodenum-preserving pancreatic head resection (DPPHR) in chronic pancreatitis: its rationale and results.

Persistent, uncontrolled pain is the most common indication for surgery in chronic pancreatitis. In the presence of an inflammatory mass in the pancreatic head or in pancreatic head-related complications of chronic pancreatitis, resection procedures are inevitable. The Whipple procedure, originally introduced for malignant lesions of the periampullary region, is commonly employed, although it represents surgical over-treatment in a benign pancreatic disorder. In this article, we discuss our long experience with duodenum-preserving pancreatic head resection (Beger procedure) for chronic pancreatitis. Prospective, randomized controlled trials suggest that this organ- and function-preserving procedure should be the gold standard for the surgical treatment of pancreatic head-related complications of chronic pancreatitis.

Adult↗
PubMed2000

Enteral nutrition prolongs delayed gastric emptying in patients after Whipple resection.

BACKGROUND: Delayed gastric emptying is one of the most frequent postoperative complications after Whipple resection. In the present study we evaluated the role of enteral nutrition in the development of delayed gastric emptying after Whipple resection. PATIENTS AND METHODS: Between January 1996 and June 1998, 64 patients (30 female, 34 male) underwent a classic (n = 27) or pylorus-preserving (n = 37) Whipple resection. Two patients were excluded; 30 patients received enteral and 32 patients received no-enteral nutrition. RESULTS: Delayed gastric emptying occurred significantly more in patients with enteral (17 of 30, 57%) than in patients with no-enteral nutrition (5 of 32, 16%) (P <0.01). Consequently, patients in the enteral nutrition group had a nasogastric tube for a significantly (P<0.01) longer period and had a significantly (P<0.01) longer hospital stay than patients in the no-enteral nutrition group. There were no differences in the frequency of occurrence of other postoperative complications between patients with enteral and no-enteral nutrition. CONCLUSION: In patients undergoing a Whipple resection, enteral nutrition is associated with a higher frequency of delayed gastric emptying with no advantages regarding other postoperative complications and should therefore be restricted to specific indications.

Adult↗
PubMed2000

Differential expression of chemokines in normal pancreas and in chronic pancreatitis.

BACKGROUND & AIMS: Cellular infiltrates are present already in early stages of chronic pancreatitis. The mechanisms responsible for their recruitment are unknown. Hence, we determined the differential expression of chemokine genes and their cellular sources in normal and affected pancreatic tissues. METHODS: Pancreatic tissues from 23 patients with chronic pancreatitis and from 4 normal controls were subjected to in situ hybridization for detecting messenger RNA (mRNA) of the chemokine genes interleukin 8, ENA-78, MIG, MCP-1, and I-309. RESULTS: Normal pancreatic tissues lack cells expressing mRNA for IL-8, ENA-78, MIG, and MCP-1. In contrast, pancreatic lobuli with mild to moderate signs of tissue alterations strongly expressed MCP-1 mRNA in centroacinar ducts, endothelia, fibroblasts, macrophages, T cells, and occasionally in nerves. Interleukin 8 and ENA-78 mRNA is preferentially detected in centroacinar ducts of pancreatic lobuli with more advanced alterations. Variable numbers of pancreas-infiltrating T cells express MIG mRNA. I-309 mRNA, however, is consistently observed in normal acini and in tissue with mild to moderate signs of tissue alterations. CONCLUSIONS: The observed differential expression of distinct chemokine genes in pancreatic parenchyma and infiltrates from patients with chronic pancreatitis strongly suggests an involvement of distinct chemokines in the initiation and perpetuation of disease.

Adult↗
PubMed2000

Chronic pancreatitis--new pathophysiological concepts.

The pathophysiology of chronic pancreatitis has been a controversial topic of discussion for decades. None of the concepts proposed up until now have been able to elucidate the course of the disease in a conclusive matter. However, with the growth of new techniques in cell and molecular biology and the ability to create genetically modified cell systems and animals, many new and potentially important mechanisms have been discovered in recent years. This article will review these new pathophysiological aspects in chronic pancreatitis, which include growth factor overexpression, inflammatory mediator activation, deregulated immune response and altered nerve growth with specific neuroimmune interactions.

Animals↗
PubMed2000

Pancreatic cancer--new aspects of molecular biology research.

Pancreatic ductal adenocarcinoma (PDAC) presently has an incidence of approximately 8 to 10 cases per 100,000 citizens in European countries, and the incidence has been increasing throughout the last decades. Approximately 30,000 patients die every year from PDAC in Western Europe and most of the newly diagnosed patients present with an already unresectable tumor stage. Self-sufficiency in growth signals, insensitivity to antigrowth signals, and evasion of apoptosis are hallmarks of malignant growth. In PDAC a variety of growth factors are expressed at increased levels. For example, the concomitant presence of the EGF-receptor and its ligands EGF, TGF-alpha, and/or amphiregulin is associated with enhanced tumor aggressiveness and shorter survival periods following tumor resection. In addition, PDACs often exhibit alterations in growth inhibitory pathways such as Smad4 mutations and Smad6 and Smad7 overexpression, and evade apoptosis through p53 mutations and aberrant expression of apoptosis regulating genes such as members of the Bcl family. Taken together, the abundance of growth promoting factors and the disturbance of growth inhibitory and apoptotic pathways give pancreatic cancer cells a distinct growth advantage which clinically results in rapid tumor progression and poor survival prognosis.

Apoptosis↗
PubMed2000

Duodenum-preserving pancreatic head resection: future standard operation in chronic pancreatitis.

As the incidence of chronic pancreatitis (CP) has risen in most industrialized countries due to increasing alcohol intake, operative therapy has gained importance, and various new operative procedures have been introduced in the past two or three decades. With pancreatic duct drainage operations, pain relief is frequently not satisfactory in long-term follow-up. Pathological studies in combination with modern molecular biology investigations, suggests that the pancreatic head is the "pacemaker" of the disease in most CP patients. Therefore, surgical procedures which aim to remove pancreatic head-related CP complications are needed in most patients. The Whipple operation, which was originally developed to treat malignancies in the pancreatic head region, follows oncological criteria and can therefore be considered surgical overtreatment in the majority of CP patients. As an alternative, the duodenum-preserving pancreatic head resection (DPPHR) was introduced by Hans Beger in 1972 to preserve the stomach, the extrahepatic bile duct and the duodenum. DPPHR is an organ-preserving surgical procedure which provides satisfactory long-term results with regard to mortality, morbidity, pain relief, weight gain and social and professional rehabilitation. Among the operations currently available, DPPHR is the best choice for a new standard operation in patients with pancreatic head-related complications.

Chronic Disease↗
PubMed2000

[Surgery of pancreatic carcinoma].

Pancreatic cancer is the third leading neoplasm of the gastrointestinal system and has a dismal prognosis. The majority of patients are no more suitable for resection at time of diagnosis due to early development of distant metastases or major infiltration of adjacent structures. However, due to the resistance of pancreatic cancer against radiation and chemotherapy, radical resection represents the only therapy with a potential for cure. For the surgical treatment of pancreatic head cancer, the classical Whipple operation is still the standard procedure but during the last two decades, pylorus-preserving pancreatoduodenectomy has been evolved as a more conservative procedure in order to omit the consequences of partial gastrectomy. For cancer of the pancreatic body and tail, distal pancreatectomy or total pancreatectomy represent the current standard treatment. More radical methods like regional pancreatectomy and resection with extended lymph node dissection have failed so far to demonstrate any improvements in long-term survival compared to the standard types of resection. To further improve the treatment of pancreatic cancer, prospectively randomized trials are needed to compare extended surgical procedures with the standard types of resection and the efficiency of various adjuvant therapies.

Adult↗
PubMed2000

Connective tissue growth factor in human liver cirrhosis.

BACKGROUND: Connective tissue growth factor (CTGF) belongs to a family of factors that regulate fibrogenesis and wound healing. While the significance of transforming growth factor beta (TGF-beta) in liver fibrosis is well established, the role of CTGF in fibrosing hepatopathy is still unknown. METHODS: CTGF was analyzed in 10 normal and in 16 cirrhotic liver tissue samples. Northern blot analysis was used to examine the concomitant expression of CTGF and TGF-beta1 mRNAs, and the cellular localization of CTGF mRNA was studied by in situ hybridization. For identification of myofibroblasts and activated hepatic stellate cells, alpha-smooth muscle actin (alpha-SMA) immunohistochemistry was used. RESULTS: Northern blot analysis showed 6.5-fold enhanced expression of CTGF mRNA and 7.8-fold enhanced expression of TGF-beta1 mRNA in liver cirrhosis in comparison with normal controls (p<0.01). By in situ hybridization, CTGF mRNA was detectable in only a few spindle cells in the portal tracts in normal liver samples. In contrast, there was strong expression of CTGF mRNA in fibroblasts and myofibroblast-like cells present in fibrous septa surrounding the cirrhotic nodules, in stellate cells, in endothelial cells and in mesenchymal cells around ductular proliferations, and in ductular epithelial cells. There was a strong correlation between CTGF mRNA and TGF-beta1 mRNA as well as the degree of fibrosis (p<0.01). CONCLUSIONS: Overexpression of CTGF in liver cirrhosis, especially in fibroblasts/myofibroblasts and stellate cells, suggests that this novel factor may play an important role in hepatic fibrosis.

Actins↗
PubMed2000

Galectin-1 and galectin-3 in chronic pancreatitis.

Galectin-1 and galectin-3 have important functions in cell-cell interactions, cell adhesion to extracellular matrix, the organization of extracellular matrix, and tissue remodeling. To assess their potential role in chronic pancreatitis (CP), we examined their expression by Northern blot analysis, in situ hybridization, immunohistochemistry, and Western blot analysis in normal and CP pancreatic tissues. Northern blot analysis revealed a 4.5-fold increase of galectin-1 mRNA (p < 0.01) and a 3.8-fold increase of galectin-3 mRNA (p < 0.01) in CP samples compared with normal controls. In situ hybridization analysis of normal pancreas indicated low abundance of galectin-1 mRNA in fibroblasts, whereas galectin-3 mRNA was moderately present in ductal cells. CP samples exhibited moderate to intense galectin-1 mRNA signals in fibroblasts, whereas galectin-3 mRNA signals were intense in the cells of ductular complexes and weak in the degenerating acinar cells. In addition, intense galectin-1 and galectin-3 mRNA signals were present in nerves of normal and CP samples. Immunohistochemistry showed a distribution pattern of galectin-1 and galectin-3 similar to that described for in situ hybridization. Relative quantification of galectin-1 and galectin-3 protein by immunoblotting revealed an increase of 3.2-fold and 3.0-fold, respectively, in CP compared with normal controls. There was a significant correlation between galectin-1 and fibrosis and between galectin-3 and fibrosis and the density of ductular complexes. Up-regulation of galectin-1 in fibroblasts and galectin-3 in ductular complexes suggests a role of these lectins in tissue remodeling in CP. Galectin-1 might participate in ECM changes, whereas galectin-3 seems to be involved in both ECM changes and ductular complex formation.

Adult↗
PubMed2000

Bombesin receptors in distinct tissue compartments of human pancreatic diseases.

Overexpression of receptors for regulatory peptides in various human diseases is reportedly of clinical interest. Among these peptides, bombesin and gastrin-releasing peptide (GRP) have been shown to play a physiological and pathophysiological role in pancreatic tissues. Our aim has been to localize bombesin receptors in the human diseased pancreas to identify potential clinical applications of bombesin analogs in this tissue. The presence of bombesin receptor subtypes has been evaluated in specimens of human pancreatic tissues with chronic pancreatitis (n = 23) and ductal pancreatic carcinoma (n = 29) with in vitro receptor autoradiography on tissue sections incubated with 125I-[Tyr4]-bombesin or the universal ligand 125I-[D-Tyr6, beta-Ala11, Phe13, Nle14]-bombesin(6-14) as radioligands and displaced by subtype-selective bombesin receptor agonists and antagonists. GRP receptors were identified in the pancreatic exocrine parenchyma in 17 of 20 cases with chronic pancreatitis. No measurable bombesin receptors were found in the tumor tissue of ductal pancreatic carcinomas, however, GRP receptors were detected in a subset of peritumoral small veins in 19 of 29 samples. Moreover, residual pancreatic islets in these tissues were shown to express the BB3 receptor subtype. These data demonstrate the presence of bombesin receptors in three distinct tissue compartments of the pancreas, namely GRP receptors in the exocrine parenchyma in chronic pancreatitis and in peritumoral vessels around ductal pancreatic carcinomas, and BB3 receptors in residual pancreatic islets. Such a selective expression of bombesin receptor subtypes in pancreatic tissues may not only be of pathophysiological significance but may represent the basis for potential diagnostic and therapeutic clinical applications of bombesin analogs, including GRP receptor scintigraphy to differentiate chronic pancreatitis from ductal pancreatic carcinoma.

Adenocarcinoma↗
PubMed2000

Pancreatic fistula after pancreatic head resection.

BACKGROUND: Pancreatic resections can be performed with great safety. However, the morbidity rate is reported to be 40-60 per cent with a high prevalence of pancreatic complications. The aim of this study was to analyse complications after pancreatic head resection, with particular attention to morbidity and pancreatic fistula. METHODS: From November 1993 to May 1999, perioperative and postoperative data from 331 consecutive patients undergoing pancreatic head resection were recorded prospectively. Data were analysed and grouped according to the procedure performed: classic Whipple resection, pylorus-preserving pancreatoduodenectomy (PPPD) or duodenum-preserving pancreatic head resection (DPPHR). RESULTS: Pancreatic head resection had a mortality rate of 2.1 per cent; the difference in mortality rate between the three groups (0.9-3.0 per cent) was not significant. Total and local morbidity rates were 38.4 and 28 per cent respectively. DPPHR had a lower morbidity, both local and systemic, than pancreatoduodenectomy. The prevalence of pancreatic fistula was 2.1 per cent in 331 patients, and was not dependent on the procedure or the aetiology of the disease. Reoperations were performed in 3.9 per cent of patients, predominantly for bleeding and non-pancreatic fistula. None of the patients with pancreatic fistula required reoperation or died in the postoperative course. CONCLUSION: A standardized technique and a continuing effort to improve perioperative management may be responsible for low mortality and surgical morbidity rates after pancreatic head resection. Pancreatic complications occur with Whipple, PPPD and DPPHR procedures with a similar prevalence. Pancreatic fistula no longer seems to be a major problem after pancreatic head resection and rarely necessitates surgical treatment.

Adolescent↗
PubMed2000

Macrophages infiltrating the tissue in chronic pancreatitis express the chemokine receptor CCR5.

BACKGROUND: The immunologic mechanisms involved in the development of chronic pancreatitis (CP) are poorly understood. Chronically inflamed tissues contain increased numbers of mononuclear cells expressing the CC chemokine receptor 5 (CCR5), which is also a coreceptor for HIV entry of macrophagetropic strains. However, whether this receptor is involved in the inflammatory process in CP is not known. In the current study, we analyzed the expression of CCR5 in CP. The detection of chemokine receptors on inflammatory cells would strongly suggest their involvement in the pathogenesis of CP (i.e., attraction and activation of these cells). To further evaluate this, we consecutively analyzed the expression of 2 ligands of CCR5: RANTES and MIP-alpha. METHODS: Pancreatic tissue samples of 22 patients with CP and of 7 healthy pancreas were evaluated. CCR5, RANTES, and MIP-1alpha were analyzed by Northern blot analysis. Consecutive tissue sections were stained for CCR5, CD3, and CD68 to define the leukocyte subtype expressing CCR5 in CP. RESULTS: By Northern blot analysis, CCR5, RANTES, and MIP-1alpha messenger RNA (mRNA) levels were 12.9-fold, 13.3-fold and 9.2-fold higher in CP specimens compared with healthy controls, respectively (P<.01). Immunostaining for CCR5 revealed a 30-fold increase of CCR5-positive cells in CP tissue compared with the healthy pancreas. Staining of consecutive tissue sections revealed that the majority of CCR5-positive cells were also CD68-positive (macrophages). CONCLUSIONS: Our data indicate that a remarkable portion of CCR5-positive cells in CP are macrophages. CCR5 is most likely involved in the attraction and activation of these macrophages, since the CCR5 ligands RANTES and MIP-1alpha are concomitantly upregulated.

Adult↗
PubMed2000

Acute necrotizing pancreatitis: treatment strategy according to the status of infection.

OBJECTIVE: To determine benefits of conservative versus surgical treatment in patients with necrotizing pancreatitis. SUMMARY BACKGROUND DATA: Infection of pancreatic necrosis is the most important risk factor contributing to death in severe acute pancreatitis, and it is generally accepted that infected pancreatic necrosis should be managed surgically. In contrast, the management of sterile pancreatic necrosis accompanied by organ failure is controversial. Recent clinical experience has provided evidence that conservative management of sterile pancreatic necrosis including early antibiotic administration seems promising. METHODS: A prospective single-center trial evaluated the role of nonsurgical management including early antibiotic treatment in patients with necrotizing pancreatitis. Pancreatic infection, if confirmed by fine-needle aspiration, was considered an indication for surgery, whereas patients without signs of pancreatic infection were treated without surgery. RESULTS: Between January 1994 and June 1999, 204 consecutive patients with acute pancreatitis were recruited. Eighty-six (42%) had necrotizing disease, of whom 57 (66%) had sterile and 29 (34%) infected necrosis. Patients with infected necrosis had more organ failures and a greater extent of necrosis compared with those with sterile necrosis. When early antibiotic treatment was used in all patients with necrotizing pancreatitis (imipenem/cilastatin), the characteristics of pancreatic infection changed to predominantly gram-positive and fungal infections. Fine-needle aspiration showed a sensitivity of 96% for detecting pancreatic infection. The death rate was 1.8% (1/56) in patients with sterile necrosis managed without surgery versus 24% (7/29) in patients with infected necrosis (P <.01). Two patients whose infected necrosis could not be diagnosed in a timely fashion died while receiving nonsurgical treatment. Thus, an intent-to-treat analysis (nonsurgical vs. surgical treatment) revealed a death rate of 5% (3/58) with conservative management versus 21% (6/28) with surgery. CONCLUSIONS: These results support nonsurgical management, including early antibiotic treatment, in patients with sterile pancreatic necrosis. Patients with infected necrosis still represent a high-risk group in severe acute pancreatitis, and for them surgical treatment seems preferable.

Adolescent↗