ADAM8 expression is associated with increased invasiveness and reduced patient survival in pancreatic cancer

ADAM8 belongs to a family of transmembrane proteins implicated in cell–cell interactions, proteolysis of membrane proteins, and various aspects of carcinogenesis. In the present study, we aimed to evaluate the expression and function of ADAM8 in pancreatic cancer. ADAM8 mRNA levels were analysed by quantitative RT-PCR and correlated to patient survival. Immunohistochemistry was performed to localize ADAM8 in pancreatic tis-sues. Silencing of ADAM8 expression was carried out by transfection with specific siRNA oligonucleotides. Cell growth and invasion assays were used to assess the functional consequences of ADAM8 silencing. SELDI-TOF-MS was performed to detect the proteolytic activity of ADAM8 in pancreatic cancer cells. ADAM8 mRNA was significantly overexpressed in pancreatic ductal adenocarcinoma (PDAC) compared with normal pancreatic tissues (5.3-fold increase; P= 0.0008), and high ADAM8 mRNA and protein expression levels correlated with reduced survival time of PDAC patients (P= 0.048 and P= 0.065, respectively). Silencing of ADAM8 expression did not significantly influence pancreatic cancer cell growth but suppressed invasiveness. In addition, decreased proteolytic activity was measured in cell culture supernatants following silencing of ADAM8. In conclusion, ADAM8 is overexpressed in PDAC, influences cancer cell invasiveness and correlates with reduced survival, suggesting that ADAM8 might be a potential target in pancreatic cancer therapy.

Regulation and functional role of the Runt-related transcription factor-2 in pancreatic cancer

Recent evidence suggests that Runt-related transcription factors play a role in different human tumours. In the present study, the localisation of the Runt-related transcription factor-2 (Runx2), its transcriptional activity, as well as its regulation of expression was analysed in human pancreatic ductal adenocarcinoma (PDAC). Quantitative real-time PCR and immunohistochemistry were used for Runx2 expression and localisation analysis. Runt-related transcription factor-2 expression was silenced using specific siRNA oligonucleotides in pancreatic cancer cells (Panc-1) and immortalised pancreatic stellate cells (IPSCs). Overexpression of Runx2 was achieved using a full-length expression vector. TGF-β1, BMP2, and other cytokines were assessed for their potential to regulate Runx2 expression. There was a 6.1-fold increase in median Runx2 mRNA levels in PDAC tissues compared to normal pancreatic tissues (P<0.0001). Runt-related transcription factor-2 was localised in pancreatic cancer cells, tubular complexes, and PanIN lesions of PDAC tissues as well as in tumour-associated fibroblasts/stellate cells. Coculture of IPSCs and Panc-1 cells, as well as treatment with TGF-β1 and BMP2, led to increased Runx2 expression in Panc-1 cells. Runt-related transcription factor-2 overexpression was associated with decreased MMP1 release as well as decreased growth and invasion of Panc-1 cells. These effects were reversed by Runx2 silencing. In conclusion, Runx2 is overexpressed in PDAC, where it is regulated by certain cytokines such as TGF-β1 and BMP2 in an auto- and paracrine manner. In addition, Runx2 has the potential to regulate the transcription of extracellular matrix modulators such as SPARC and MMP1, thereby influencing the tumour microenvironment.

Fast track--different implications in pancreatic surgery

Concepts in "fast-track" surgery, which provide optimal perioperative care, have been proven to significantly reduce complication rates and decrease hospital stay. This study explores whether fast-track concepts can also be safely applied and improve the outcomes of major pancreatic resections. Perioperative data from 255 consecutive patients, who underwent pancreatic resection by means of fast-track surgery in a high-volume medical center, were analyzed using univariate and multivariate models. Of the 255 patients, 180 received a pancreatic head resection and 51 received distal, 15 received total, and 9 received segmental pancreatectomies. The patients were discharged on median day 10 with a 30-day readmission rate of 3.5%. The in-hospital mortality was 2%, whereas medical and surgical morbidities were 17 and 25%, respectively. Fast-track parameters, such as first stools, normal food, complete mobilization, and return to normal ward, correlated significantly with early discharge (p < 0.05). Patients' age, operation time, and early extubation proved to be independent factors of early discharge, shown through multivariate analysis (odds ratio: 4.0, 2.0, and 2.8, respectively; p < 0.05). Low readmission, mortality, and morbidity rates demonstrate that fast-track surgery is in fact feasible and safe and promotes earlier discharge without compromising patient outcomes.

Cetuximab in combination with intensity modulated radiotherapy (IMRT) and gemcitabine for patients with locally advanced pancreatic cancer: A prospective phase II trial [PARC-Study ISRCTN56652283]

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Background: The induction of EGFR targeting with cetuximab in radiation based therapy of solid tumors has yielded promising results. Thus, we initiated a prospective phase II trial designed to analyze the feasibility and effectivity of trimodal therapy with gemcitabine-based chemoradiation and cetuximab in locally advanced inoperable pancreatic cancer. Methods: In this phase 2 study, pts with locally advanced pancreatic cancer without prior cytotoxic therapy were treated with radiotherapy (RT), gemcitabine weekly (300mg/m2), and cetuximab weekly (loading dose 400mg/m2 day 1, and concomitant with radiation day 8,15,22,29,36 250mg/m2). RT was delivered by using an integrated IMRT boost concept (54 Gy GTV, 45 Gy CTV) over 5 weeks. RT was followed by gemcitabine (1,000mg/m2) weekly x 3 in 4 weeks. Response evaluation using CT followed at week 12. All pts were intended for surgical treatment between week 12–15. Pts were followed for adverse events and response. Results: 55 pts were enrolled. Preliminary results are presented on 36 pts with the following characteristics: pancreatic adenocarcinoma c2 T4 N1 36/36, median age = 61.5 (range 48–79); M/F = 24/12; ECOG PS 0/1/2 = 6/26/4; median days on treatment: 90 (range 70–100). Treatment-related toxicities were observed in 22 pts. Grade 3 toxicities included diarrhea (n=5), fatigue (n=4), nausea (n=6), neutropenia (n=10), thrombocytopenia (n=4), and vomiting (n=4). 34/36 pts developed some acneiforme rush during therapy. No omittance of cetuximab was necessary in any of the pts. 1 patient died during treatment due to tumor bleeding. Median follow-up at present is 13 month, 1-year survival was 57%, median survival has not been reached. Partial remissions 12/36, stable disease 20/36, progressive disease 4/36 (RECIST). 21/36 pts were amenable for secondary potentially curative resection. 9 pts could be resected, while 8 pts were found to have abdominal metastatic spread. Conclusions: Early data from trimodal therapy in pancreatic adenocarcinoma with chemoradiation (IMRT), gemcitabine, and cetuximab indicate feasibility without increased toxicity profile. The local response appears to be very promising in pancreatic cancer.

[Table: see text]

Neoadjuvant therapy for pancreatic cancer

No good evidence of benefit—trials needed

Systematic review and meta-analysis of standard and extended lymphadenectomy in pancreaticoduodenectomy for pancreatic cancer

BACKGROUND

Although some retrospective studies of extended radical lymphadenectomy for pancreatic cancer have suggested a survival advantage, this is controversial.

METHODS

A literature search identified randomized controlled trials comparing extended with standard lymphadenectomy in pancreatic cancer surgery. Overall survival was analysed using hazard ratios and standard errors. Pooled estimates of overall treatment effects were calculated using a random effects model (odds ratio and 95 per cent confidence interval).

RESULTS

Of four randomized trials identified for systematic review, three were included in a meta-analysis of survival. The log hazard ratios (standard errors) for survival for the three trials were 0.36 (0.22), - 0.15 (0.17) and - 0.21 (0.15); the weighted mean log hazard ratio for survival overall was 0.93 (95 per cent confidence interval 0.77 to 1.13), revealing no significant differences between the standard and extended procedure (P = 0.480). Morbidity and mortality rates were also comparable, with a trend towards higher rates of delayed gastric emptying for extended lymphadenectomy. The number of resected lymph nodes was significantly higher in the extended lymphadenectomy groups (P < 0.001).

CONCLUSION

The extended procedure does not benefit overall survival, and there may even be a trend towards increased morbidity. Therefore extended lymphadenectomy should be performed only within adequately powered controlled trials, if at all.

Extended Donor Criteria Have No Negative Impact on Early Outcome After Liver Transplantation: A Single-Center Multivariate Analysis

The organ shortage has driven many transplant centers to accept extended donor criteria and to modify graft allocation policies. This study was designed to analyze the impact of applying extended donor criteria (EDC) in orthotopic liver transplantation (OLT). Between December 2001 and December 2004, we performed 165 primary cadaveric whole OLTs. Up to three EDC, that is, ventilation >7 days; aminotransferases (ALT or AST) >3 x normal; bilirubin >3 mg/dL; anti-HBc or HBs Ag positivity; donor age >65 years; liver steatosis >40%; donor body mass index >30; cold ischemia time >14 hours; peak serum Na(+) >165 mmol/L; history of extrahepatic malignancy; or previous drug abuse were present in 55% of all grafts. Both univariate and multivariate analysis revealed that EDC status had no effect on graft or patient survival, the necessity for retransplantation, the length of intensive care/intermediate care unit stay, mechanical ventilation, complications, or posttransplant laboratory findings. Recipient age of >/=55 years was the only independent prognostic factor for survival, regardless of EDC. These findings suggested that the use of grafts from EDC donors are safe and expand the donor pool.

Phosphatidylinositol 3-kinase facilitates bile acid-induced Ca(2+) responses in pancreatic acinar cells

Bile acids are known to induce Ca(2+) signals in pancreatic acinar cells. We have recently shown that phosphatidylinositol 3-kinase (PI3K) regulates changes in free cytosolic Ca(2+) concentration ([Ca(2+)](i)) elicited by CCK by inhibiting sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA). The present study sought to determine whether PI3K regulates bile acid-induced [Ca(2+)](i) responses. In pancreatic acinar cells, pharmacological inhibition of PI3K with LY-294002 or wortmannin inhibited [Ca(2+)](i) responses to taurolithocholic acid 3-sulfate (TLC-S) and taurochenodeoxycholate (TCDC). Furthermore, genetic deletion of the PI3K gamma-isoform also decreased [Ca(2+)](i) responses to bile acids. Depletion of CCK-sensitive intracellular Ca(2+) pools or application of caffeine inhibited bile acid-induced [Ca(2+)](i) signals, indicating that bile acids release Ca(2+) from agonist-sensitive endoplasmic reticulum (ER) stores via an inositol (1,4,5)-trisphosphate-dependent mechanism. PI3K inhibitors increased the amount of Ca(2+) in intracellular stores during the exposure of acinar cells to bile acids, suggesting that PI3K negatively regulates SERCA-dependent Ca(2+) reloading into the ER. Bile acids inhibited Ca(2+) reloading into ER in permeabilized acinar cells. This effect was augmented by phosphatidylinositol (3,4,5)-trisphosphate (PIP(3)), suggesting that both bile acids and PI3K act synergistically to inhibit SERCA. Furthermore, inhibition of PI3K by LY-294002 completely inhibited trypsinogen activation caused by the bile acid TLC-S. Our results indicate that PI3K and its product, PIP(3), facilitate bile acid-induced [Ca(2+)](i) responses in pancreatic acinar cells through inhibition of SERCA-dependent Ca(2+) reloading into the ER and that bile acid-induced trypsinogen activation is mediated by PI3K. The findings have important implications for the mechanism of acute pancreatitis since [Ca(2+)](i) increases and trypsinogen activation mediate key pathological processes in this disorder.

Surgical treatment of pancreatic cancer: the role of adjuvant and multimodal therapies

Surgical treatment in specialized referral centers has improved the prognosis of resectable pancreatic cancer considerably despite the generally aggressive behavior of this malignancy. At the same time, adjuvant therapy for pancreatic cancer has been shown to be effective in providing a survival benefit. However, some controversy remains over whether to use chemotherapy alone or combined chemoradiation. Few prospective randomized controlled clinical trials (RCTs) on the use of adjuvant chemotherapy and chemoradiation have demonstrated a distinct survival advantage of systemic chemotherapy (5-FU/FA or gemcitabine) following surgical resection. The most notable published trial is the European Study Group for Pancreatic Cancer (ESPAC)-1 trial. In addition, there are several retrospective analyses and two randomized studies on adjuvant radiation and chemoradiation. Some of these suggested increased survival rates using chemoradiation, which was subsequently widely introduced in clinical routine, especially in the United States. RCTs and a recent meta-analysis of these RCTs confirm, however, the superiority of chemotherapy over chemoradiation, except for a subgroup of patients with positive resection margins. Thus, curative surgery followed by adjuvant systemic chemotherapy should be the standard treatment for patients with resectable, locally confined pancreatic cancer. Further RCTs may clarify potential benefits of chemoradiation in the adjuvant treatment setting. Moreover, the best chemotherapy, or a combination thereof, remains to be determined in large-scale randomized trials.

[Results and significance of lymphadenectomy in pancreatic cancer]

Pancreatic adenocarcinoma is one of the most aggressive human solid tumors with a 5-year survival rate of less than 5%. The only chance for cure is complete resection of the tumor. This can be achieved in approximately 8-15% of all cases since solely localized tumors and a small part of locally advanced carcinomas may be resected. However, many patients suffer from a local relapse after surgical therapy. In order to improve the long-term survival of surgically treated patients, extended lymphadenectomy after partial duodenopancreatectomy was introduced. Some retrospective studies from the 80 s showed improved survival rates for those patients in whom extended lymphadenectomy was performed. However, these results were not confirmed in following randomised controlled prospective studies. Extended lymphadenectomy can be performed with slightly increased morbidity and equal mortality but survival is not improved. Therefore, standard lymphadenectomy is recommended in patients undergoing duodenopancreatectomy for pancreatic cancer. Extended lymphadenectomy (with retroperitoneal clearance) should only be accomplished within controlled clinical studies.

Detection of 2-amino-1-methyl-6-phenylimidazo [4,5-b]-pyridine (PhIP)-DNA adducts in human pancreatic tissues

Recent epidemiological investigations have observed an association between the consumption of grilled or barbecued meat and an increased risk of pancreatic cancer, suggesting that dietary exposure to heterocyclic aromatic amines (HCA) may contribute to the development of this disease. 2-Amino-1-methyl-6-phenylimidazo [4,5-b]-pyridine (PhIP) is the most abundant HCA found in well-done and grilled meats. To determine whether HCA-induced DNA damage is present in the human pancreas, immunohistochemistry and computer-assisted image analysis were used to measure PhIP-DNA adducts in 54 normal pancreatic tissues (N) from persons without pancreatic cancer and in 38 normal adjacent pancreatic tissues (A) and in 39 cancer tissues (T) from 68 patients with pancreatic adenocarcinoma. PhIP-DNA adducts were detected in 53 N, 34 A and 39 T samples. Mean values (+/-SD) of the absorbency for PhIP staining were 0.22+/-0.04, 0.24+/-0.04, and 0.24+/-0.03 for N, A, and T samples, respectively (p=0.004). Using the median absorbency (0.21) of the samples from normal controls as the cut-off, 71% of A and 77% of T tissues, compared with 48% of N tissues, were distributed in the higher range (p=0.009). The odds ratio of pancreatic cancer was 3.4 (95% confidence interval 1.5-7.5, p=0.002) for individuals with a higher level of PhIP-DNA adducts. This is the first report of the detection of PhIP-DNA adducts in human pancreatic tissue samples obtained from patients with unknown exposure to HCA. Although limited by the small sample size, these preliminary results suggest that PhIP exposure may contribute to human pancreatic cancer development.

Postoperativer Ileus

Continuous improvements in surgical technique and anaesthesia for ileus have resulted in a significant reduction of perioperative complications. Postoperative outcome of surgical patients is increasingly dependent on the severity of postoperative ileus, which often determines morbidity and length of hospital stay. In the present article we discuss possible variables influencing this disease. Furthermore, means of prevention and therapeutic strategies for postoperative ileus are briefly presented.

[Autoimmune pancreatitis--a surgical disease?]

The term autoimmune pancreatitis (AIP) describes a nonalcoholic, chronic lymphoplasmocytic pancreatitis. The lymphoplasmocytic infiltration is characterized by periductal localization of predominantly CD4-positive T cells, fibrosis, and acinar atrophy, frequently resulting in stenosis of the main pancreatic and distal common bile ducts. Imaging studies often reveal a diffuse narrowing of the pancreatic main duct and swelling of the pancreatic head wrongly suggesting the presence of a malignant tumor. Clinical signs include mild abdominal pain, jaundice, recurrent episodes of acute pancreatitis, and even new-onset diabetes mellitus. Additionally, AIP can be associated with other autoimmune diseases such as Sjögren's syndrome, primary sclerosing cholangitis, chronic inflammatory bowel diseases, and retroperitoneal fibrosis. Serological markers include autoantibodies and increased levels of gamma globulin and especially IgG4. Steroids seem to be effective in improving clinical symptoms as well as in the resolution of pancreatic and bile duct narrowing. This distinguishes AIP from other forms of pancreatitis and from pancreatic neoplasms. Further studies of the underlying pathophysiologic mechanisms, prognosis, and new diagnostic tools are needed to provide adequate and effective treatment in the future. In this article, we summarize the current knowledge about AIP and present 17 cases that underwent surgical resection at our institution from 2003 to 2004.

Polymorphisms of UDP-glucuronosyltransferase 1A7 are not involved in pancreatic diseases

BACKGROUND

Xenobiotic mediated cellular injury is thought to play a major role in the pathogenesis of pancreatic diseases. Genetic variations that reduce the expression or activity of detoxifying phase II biotransformation enzymes such as the UDP-glucuronosyltransferases might be important in this respect. Recently, a UGT1A7 low detoxification activity allele, UGT1A7*3, has been linked to pancreatic cancer and alcoholic chronic pancreatitis.

OBJECTIVE

To investigate whether UGT1A7 polymorphisms contribute to the risk of pancreatitis and pancreatic cancer.

METHODS

Genetic polymorphisms in the UGT1A7 gene were assessed in a large cohort of patients with different types of pancreatitis and pancreatic cancer originating from the Czech Republic (n = 93), Germany (n = 638), Netherlands (n = 136), and Switzerland (n = 106), and in healthy (n = 1409) and alcoholic (n = 123) controls from the same populations. Polymorphisms were determined by melting curve analysis using fluorescence resonance energy transfer probes. In addition, 229 Dutch subjects were analysed by restriction fragment length polymorphism.

RESULTS

The frequencies of UGT1A7 genotypes did not differ between patients with acute or chronic pancreatitis or pancreatic adenocarcinoma and alcoholic and healthy controls.

CONCLUSIONS

The data suggest that, in contrast to earlier studies, UGT1A7 polymorphisms do not predispose patients to the development of pancreatic cancer and pancreatitis.

Development and evaluation of a training module for the clinical introduction of the da Vinci robotic system in visceral and vascular surgery

BACKGROUND

With the increasing use of the surgical robotic system in the clinical arena, appropriate training programs and assessment systems need to be established for mastery of this new technology. The authors aimed to design and evaluate a clinic-like training program for the clinical introduction of the da Vinci robotic system in visceral and vascular surgery.

METHODS

Four trainees with different surgical levels of experience participated in this study using the da Vinci telemanipulator. Each participant started with an initial evaluation stage composed of standardized visceral and vascular operations (cholecystectomy, gastrotomy, anastomosis of the small intestine, and anastomosis of the aorta) in a porcine model. Then the participants went on to the training stage with the rat model, performing standardized visceral and vascular operations (gastrotomy, anastomosis of the large and small intestines, and anastomosis of the aorta) four times in four rats. The final evaluation stage was again identical to the initial stage. The operative times, the number of complications, and the performance quality of the participants were compared between the two evaluation stages to assess the impact of the training stage on the results.

RESULTS

The operative times in the final evaluation stage were considerably shorter than in the initial evaluation stage and, except for cholecystectomies, all the differences reached statistical significance. Also, significantly fewer complications and improved quality for each operation in the final evaluation stage were documented, as compared with their counterparts in the initial evaluation stage. These improvements were recorded at each level of experience.

CONCLUSIONS

The presented experimental small and large animal model is a standardized and reproducible training method for robotic surgery that allows evaluation of the surgical performance while shortening and optimizing the learning-curve.

Randomized clinical trial of the influence of local water-filtered infrared A irradiation on wound healing after abdominal surgery

Background

Postoperative local water-filtered infrared A (wIRA) irradiation improves tissue oxygen partial pressure, tissue perfusion and tissue temperature, which are important in wound healing.

Methods

The effect of wIRA irradiation on abdominal wound healing following elective gastrointestinal surgery was evaluated. Some 111 patients undergoing moderate to major abdominal surgery were randomized into one of two groups: wIRA and visible light irradiation (wIRA group) or visible light irradiation alone (control group). Uncovered wounds were irradiated twice a day for 20 min from days 2–10 after operation.

Results

Irradiation with wIRA improved postoperative wound healing in comparison to visible light irradiation alone. Main variables of interest were: wound healing assessed on a visual analogue scale (VAS) by the surgeon (median 88·6 versus 78·5 respectively; P &lt; 0·001) or patient (median 85·8 versus 81·0; P = 0·040), postoperative pain (median decrease in VAS score during irradiation 13·4 versus 0; P &lt; 0·001), subcutaneous oxygen tension after irradiation (median 41·6 versus 30·2 mmHg; P &lt; 0·001) and subcutaneous temperature after irradiation (median 38·9 versus 36·4 °C; P &lt; 0·001). The overall result, in terms of wound healing, pain and cosmesis, measured on a VAS by the surgeon (median 79·0 versus 46·8; P &lt; 0·001) or patient (79·0 versus 50·2; P &lt; 0·001) was better after wIRA irradiation.

Conclusion

Postoperative irradiation with wIRA can improve normal postoperative wound healing and may reduce costs in gastrointestinal surgery.