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ABSTRACT: BACKGROUND: Decision making for adjuvant chemotherapy in stage III colon cancer is based on the TNM system. It is well known that prognosis worsens with higher pN classification, and several recent studies propose superiority of the lymph node ratio (ln ratio) to the TNM system. Therefore, we compared the prognosis of ln ratio to TNM system in our stage III colon cancer patients. METHODS: A total of 939 patients underwent radical surgery for colorectal cancer between January 2000 and December 2009. From this pool of patients, 142 colon cancer stage III patients were identified and taken for this analysis. Using martingale residuals, this cohort could be separated into a group with a low ln ratio and one with a high ln ratio. These groups were compared to pN1 and pN2 of the TNM system. RESULTS: For ln ratio, the cutoff was calculated at 0.2. There was a good prognosis of disease-free and cancer-related survival for the N-category of the TNM system as well as for the lymph node ratio. There was no statistical difference between using the N-category of the TNM system and the ln ratio. CONCLUSIONS: There might not be a benefit in using the lymph node ratio rather than the N category of the TNM system as long as the number of subgroups is not increased. In our consideration, there is no need to change the N categorization of the TNM system to the ln ratio.
World Journal of Surgical Oncology 03/2013; 11(1):79. · 1.12 Impact Factor
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ABSTRACT: The quality of a histopathologic workup after oncologic resection of pancreatic malignancies has changed the central role of surgery substantially for radical tumor clearance over the past years. The development of standardized protocols for pathologic workup increased the rate of R1 resections from around 20% up to 80%. In the present study, we investigated the incidence of R1 and its impact on survival after oncologic pancreatic resections using a standardized pathologic routine protocol.
We performed 265 pancreatic resections from September 2003 to September 2010. Among 128 patients with malignant neoplasms, histology revealed ductal pancreatic adenocarcinoma in 97, ampullary cancer in 10, and distal bile duct cancer in 21 patients. Resected specimens were analyzed according to this improved standardized pathology protocol introduced in 2000. Follow-up data on overall and cancer-related survival, presence and site of tumor recurrence, and chemotherapy were obtained from 120 patients.
Pancreatic resection comprised a pylorus-preserving or classical pancreaticoduodenectomy in 112, a distal pancreatectomy in 8, and a total pancreatectomy in 7 patients. In the overall series, 56 (44%) were classified R1 resections and 68 (43%) R0 resections, 3 patients with R2 resections were excluded, leaving 125 patients for analysis. In pancreatic adenocarcinoma, the rate of R1 was 51% (48/94). R1 resection involved most frequently the circumferential margin in 86% (48/125) of the total group and in 92% (44/48) in pancreatic cancer. Follow-up was performed after a median of 17 months (range, 1-85) postoperatively. Cancer-related death rate in R0 and R1-resected patients was 60% and 83% (P < .02) in all cancers (n = 117) and 66% and 80% in patients with pancreatic adenocarcinoma (n = 88). Median tumor-related survival in R0 and R1 resections was 22 (range, 4-85) vs 14 months (range, 2-48) in all cancers (P < .002), and 19 (range, 4-85) vs 14 months (range, 2-48) in pancreatic adenocarcinoma (P < .04). Kaplan-Meier survival analysis revealed a survival benefit after R0 resection in both all cancers (P = .002) and pancreatic adenocarcinoma (P < .02). The pattern of tumor recurrence had a greater rate of regional metastases in the R1 group (P < .05).
Our 51% rate of R1 resections in ductal pancreatic carcinoma indicates a high quality standard of pathologic evaluation. The vast majority of R1 margins are located at the retroperitoneal dissection surface. Standardization of histopathologic analysis has a clinically relevant impact on survival after oncologic resection of pancreatic cancer and can be achieved by less extensive protocols.
Surgery 07/2012; 152(3 Suppl 1):S103-11. · 3.10 Impact Factor
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ABSTRACT: Discussion of the volume-outcome relationship in pancreatic surgery has gained increasing interest. Currently, no data describe the situation in Germany. Pursuant to a recent legislative reform, a threshold of 10 operations per year was introduced for pancreatic surgery in 2006. This study describes the situation in Germany and the effect of the legislative reform between 2006 and 2009.
In 2007 and 2010, anonymous questionnaires were sent to leading surgeons in the German Society of General and Gastrointestinal Surgery asking for the numbers of pancreatic operations, methods of operation, and mortality for the years 2006, 2008, and 2009. Volume categories were defined by dividing hospitals into quartiles according to their annual volume of operations.
The return rate was about 48%. In the years 2006, 2008, and 2009, overall mortality in all hospitals was 2.85%, 3.98%, and 2.58%. High volume was defined as ≥ 32 pancreatic operations (2006) and ≥ 34 pancreatic operations (2008, 2009). Although mortality decreased with increasing volume, mortality between each volume category was not statistically different in any year. In the years 2006, 2008, and 2009, the number of operations increased in university hospitals (38.4%, 51.2%, and 50.4%, P < .001) and decreased in teaching hospitals (51.8%, 41.3%, and 41.2%, P < .001). The number of hospitals that did not perform pancreatic operations increased from 15.6% to 32.5% and 31% (P < .001).
In pancreatic surgery, a centralization effect occurred after a legislative reform in Germany. Overall mortality after pancreatic resection in German hospitals is good. Although mortality decreases with greater volume, there were no differences compared to other volume categories. Also, low-volume hospitals can produce good results; however, the difference in quality is considerable among these institutions. Our data suggest that the German threshold agreement in pancreatic surgery might have a positive effect with regard to reproducible quality and outcome.
Surgery 07/2012; 152(3 Suppl 1):S50-5. · 3.10 Impact Factor
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ABSTRACT: Treatment decisions in colorectal cancer subsequent to surgery are based mainly on the TNM system. There is a need to establish novel prognostic markers based on the molecular characterization of tumor cells. Evidence exists that sialyl Le(X) expression is correlated with an unfavorable outcome in colorectal cancer. The aim of this study was to establish a simple sialyl Le(X) staining score and to determine a potential correlation with the prognosis in a series of advanced colorectal carcinoma patients.
In order to implement routine use of sialyl Le(X) immunohistology, we established a new, easily reproducible score and defined a cutoff which discriminated groups with better or worse outcome, respectively. We then correlated sialyl Le(X) expression of 215 UICC stage III and IV patients with disease-free and cancer-related survival.
A five-stage score could be established based on automated immunohistochemical stainings. Using a statistical model, we calculated a cutoff to discriminate between weak and strong staining positivity of sialyl Le(X). Patients with strong positive specimens had a worse cancer-related survival (P = 0.004) but no difference was observed for disease-free survival (P = 0.352).
These results demonstrate a strong correlation between high sialyl Le(X)-expression in colorectal carcinomas and cancer-related survival. Our highly standardized and easy-to-use staining score is suitable for routine use and hence it could be recommended to evaluate sialyl Le(X)-expression as part of the standard histopathological analysis of colorectal carcinomas and to validate the score prospectively based on a larger population.
World Journal of Surgical Oncology 05/2012; 10:95. · 1.12 Impact Factor
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ABSTRACT: Early surgical intervention in necrotizing pancreatitis (NP) is associated with high mortality. Guidelines recommend fine needle aspiration (FNA) in patients with NP and signs of sepsis. Because infection of necrosis is considered an indication for surgery, operations are often performed early. We changed treatment toward a conservative approach with FNA in selected cases only, thereby reducing the rate of necrosectomy.
Retrospectively analyzed patients, all operated on for FNA-proven infection of pancreatic necrosis (n = 20, group 1) were compared to patients subjected to conservative treatment (n = 24, group 2) who were followed prospectively.
Prognostic scores did not differ between the two groups, indicating comparable severity: the Acute Physiology and Chronic Health Evaluation (APACHE II) score was 19.8 ± 1.7 versus 16 ± 2.2; the Sequential Organ Failure Assessment (SOFA) score was 8.7 ± 1.4 versus 6.9 ± 1.0, the C-reactive protein (CRP) level on day 3 was 243 ± 21 versus 291 ± 21, and the CTSI (CT severity index) was 7.8 ± 0.5 versus 7.9 ± 0.4 (p = ns). Ten patients in group 2 underwent operation because of severe extrapancreatic complications. Mortality differed significantly (45% in group 1 vs. 8.3% in group 2; p = 0.01).
A highly conservative approach avoiding open necrosectomy in NP results in significantly lower mortality than previous serial FNA and consecutive indication for surgery in case of proven infection. Open surgery in NP should be reserved for concomitant intra-abdominal complications.
World Journal of Surgery 03/2012; 36(5):1142-7. · 2.36 Impact Factor
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ABSTRACT: Trypsinogen activation, oxygen radicals, cytokines, leukocyte infiltration, and pancreatic ischemia are important steps in the pathogenesis of necrotizing pancreatitis and associated systemic complications. Several drugs that inhibit those pathogenetic steps attenuated biochemical and histologic changes, while survival remained low. The aim of the present study was to evaluate the benefit of multidrug approaches compared to monotherapies on organ injury and survival in acute experimental pancreatitis in the rat model of retrograde bile injection combined with intravenous cerulein.
Necrotizing pancreatitis was induced in rats. After a therapy-free interval of 6 hours, 10 treatment regimens were evaluated: multidrug regimen 1, which contained the protease inhibitor gabexate mesilate, oxygen-free radical scavengers, nitric oxide donor L-arginine, a platelet-activating factor antagonist, and antibodies against intracellular adhesion molecule-1 (ICAM-1) dissolved in dextran, was compared to multidrug regimen 2 (dextran, acetylcysteine, L-arginine, and anti-ICAM-1), monotherapies of each of the drugs, and standard intravascular volume replacement.
Both multidrug regimens significantly reduced pancreatic and systemic injury and microcirculatory disturbances compared to any of the monotherapies. Treatment with regimen 1 decreased 24-hour mortality to 0% and increased long-term survival to 85% (standard therapy, 70% and 15%, respectively). Multidrug regimen 2 was as effective as regimen 1.
Treatment of acute necrotizing pancreatitis with multidrug regimens significantly decreases short-term mortality compared to monotherapies. Moreover, multidrug strategies are still effective after a wide therapeutic window. Key to this effective therapy is the inhibition of microcirculatory disturbances and of the systemic inflammatory response. The experimental superiority of the multidrug approach should be confirmed in a clinical trial.
Surgery 03/2012; 151(3):372-81. · 3.10 Impact Factor
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ABSTRACT: Immunotherapeutic strategies become more and more important for cancer treatment. Therapeutic monoclonal antibodies (mAbs) like Panitumumab binding and blocking the EGF-receptor are in routine clinical use for the treatment of colorectal carcinoma (CRC). Also, bacterial therapy proved beneficial for experimental treatment of different tumor entities. The latter has been attributed to an activation of the immune system. Here, we describe a combination of both immunotherapeutic approaches in order to develop a novel targeted therapy for CRC. The therapeutic mAbs Trastuzumab and Panitumumab were conjugated to heat-inactivated bacteria expressing protein A or protein G. The potential of the conjugates was tested in comparison to the single components both in vitro and in vivo using a panel of patient-derived CRC cell lines. Antitumoral effects observed in vitro were strictly dependent on the presence of bacteria. Generally, effects could be enhanced by the addition of human lymphocytes. Detailed analysis of effector cells in autologous and allogeneic long-term stimulated lymphocyte cultures revealed the predominance of NK-cell-like cytolytic effectors. Reactivity was observed both against CRC target cells but also against the NK cell target K562. Similarly, in a subsequent in vivo study we observed substantial tumor growth delay accompanied by an increase in circulating NK cells. Contrary to this, the monotherapy with mAb alone caused only marginal effects and the treatment with bacteria was comparable to the mock-treated control. These data demonstrate successful targeting of CRC by bacteria/mAb conjugates. This novel concept may be interesting for future clinical approaches. Additionally, it illustrates the effectiveness of NK cells for cancer immunotherapy.
Vaccine 02/2012; 30(17):2786-94. · 3.77 Impact Factor
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ABSTRACT: In the early postoperative period after pancreas-kidney transplantation, pancreatic venous thrombosis is a major complication that leads to allograft dysfunction and graft loss. Beside ischemia and reperfusion injury, immunosuppressive drugs have been accused of supporting thrombogenicity. The aim of this study was to evaluate the effect of commonly applied immunosuppressants on microvascular thrombus formation in normal and postischemic tissue in vivo.
In the skin fold chambers of tacrolimus-, cyclosporine A-, antithymocyte globulin-, rapamycine-, or saline-treated mice, light/dye-induced microvascular thrombus formation was studied. Additional mice underwent ischemia and reperfusion of the skin fold chamber tissue and received tacrolimus, antithymocyte globulin, or saline before reperfusion. Additionally, the effect of prednisolone was tested in animals with ischemia and reperfusion. Concentrations of sP-selectin, soluble vascular cell adhesion molecule-1, and asymmetric dimethylarginine were assessed by enzyme-linked immunosorbent assay. Immunohistochemistry of the skin fold chamber tissue served for analysis of vascular endothelial nitric oxide synthase and inducible nitric oxide synthase expression.
In normal tissue, tacrolimus, cyclosporine A, antithymocyte globulin, and rapamycine accelerated microvascular thrombus formation significantly when compared with saline. Whereas ischemia and reperfusion in saline-treated mice enhanced thrombus formation, thrombogenicity was not further increased by ischemia and reperfusion in tacrolimus- or antithymocyte globulin-treated animals. Application of prednisolone reversed the tacrolimus- and antithymocyte globulin-induced prothrombotic effect. Antithymocyte globulin increased sP-selectin and soluble vascular cell adhesion molecule-1, whereas tacrolimus induced asymmetric dimethylarginine production significantly. While tacrolimus and antithymocyte globulin additionally induced endothelial nitric oxide synthase and inducible nitric oxide synthase expression, cyclosporine A influenced only endothelial inducible nitric oxide synthase expression.
Immunosuppressants enhance thrombus formation in vivo. Although antithymocyte globulin activates the microvascular endothelium, we show for the first time that tacrolimus increases asymmetric dimethylarginine plasma levels. Thus, impaired nitric oxide availability might be the underlying mechanism for the tacrolimus-associated increased thrombogenicity. The efficacy of prednisolone to reverse the tacrolimus-associated and antithymocyte globulin-associated acceleration of thrombus formation underlines the application of this anti-inflammatory drug prior to reperfusion in immunosuppressive regimens.
Surgery 01/2012; 151(1):26-36. · 3.10 Impact Factor
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ABSTRACT: Tumor infiltrating B cells (TiBc) have not yet been investigated in detail. This may at least in part be due to technical difficulties. Here we describe a straightforward and reproducible method to isolate and culture TiBc from primary colorectal carcinomas (CRC).
TiBc cultures were generated by Epstein-Barr virus (EBV) immortalization. With this method, monoclonal TiBc cultures were obtained for 14/19 CRCs. As assessed by flow cytometry and ELISA, TiBc showed an activated immunophenotype (CD23(+), CD80(+)) and produced immunoglobulin (Ig; IgG secretion in 55% of the cultures). In functional in vitro analysis, most of the IgGs specifically bound to allogeneic CRC target cells. These data suggest that TiBc are antigen-experienced and thus may exhibit functionality in situ. Additionally, mini-cultures generated from 12 further CRCs revealed TiBc outgrowth exclusively in the presence of EBV.
In summary, this simple method provides a cellular tool and our data set the stage for analysing the bivalent role of TiBc; being antigen-presenting cells on the one hand and tumor-specific antibody producers on the other. Additionally, the generation of long-term TiBc cultures and their monoclonal Ig may serve to identify novel tumor-specific antigens.
PLoS ONE 01/2012; 7(2):e32639. · 4.09 Impact Factor
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ABSTRACT: Cancer immunotherapy using bacteria dates back over 150 years. The deeper understanding on how the immune system interferes with the tumor microenvironment has led to the re-emergence of bacteria or their related products in immunotherapeutic concepts. In this review, we discuss recent approaches on experimental bacteriolytic therapy, emphasizing the specific interplay between bacteria, immune cells and tumor cells to break the tumor-induced tolerance.
Experimental research during the last decades demonstrated beneficial but also adverse influence of bacteria on tumor growth. There is a strong correlation between chronic infections and tumor incidence. However, acute bacterial infections have favourable effects on tumor growth often contributing to complete remission. Tumor regression is usually attributable to both direct tumor cell killing (via apoptosis and/or necrosis, depending on the applied bacteria) and indirect immune stimulation. This includes (I) elimination of immunosuppressive immune cells (i.e. tumor-associated macrophages, myeloid-derived suppressor, and regulatory T cells), (II) suppression of Th2-directed cytokine secretion (TGFα, IL10), (III) providing a pro-inflammatory micro-milieu (tumor infiltrating neutrophils) and (IV) supporting the influx of cytotoxic T cells into tumors. This finally forces the development of an immunological memory and may provide long-term protection against cancer.
Immunotherapy using bacteria is still a double-edged sword. Experiences from the last years have substantially contributed to when bacteria and defined components thereof might be integrated into immunotherapeutic concepts. Attempts in transferring this approach into the clinics are on their way.
Langenbeck s Archives of Surgery 12/2011; 397(4):557-68. · 1.81 Impact Factor
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ABSTRACT: Multidrug resistance (MDR) is a clinically, highly relevant phenomenon. Under chemotherapy many tumors show an increasing resistance towards the applied substance(s) and to a certain extent also towards other agents. An important molecular cause of this phenomenon is an increased expression of transporter proteins. The functional relationship between high expression levels and chemotherapy resistance makes these MDR and MRP (MDR related protein) proteins to interesting therapeutic targets. We here wanted to systematically analyze, whether these proteins are tumor specific antigens which could be targeted immunologically.
Using the reverse immunology approach, 30 HLA-A2.1 restricted MDR and MRP derived peptides (MDP) were selected. Stimulated T cell lines grew well and mainly contained activated CD8+ cells. Peptide specificity and HLA-A2.1 restriction were proven in IFN-γ-ELISpot analyses and in cytotoxicity tests against MDP loaded target cells for a total of twelve peptides derived from MDR-1, MDR-3, MRP-1, MRP-2, MRP-3 and MRP-5. Of note, two of these epitopes are shared between MDR-1 and MDR-3 as well as MRP-2 and MRP-3. However, comparably weak cytotoxic activities were additionally observed against HLA-A2.1+ tumor cells even after upregulation of MDR protein expression by in vitro chemotherapy.
Taken together, these data demonstrate that human T cells can be sensitised towards MDPs and hence, there is no absolute immunological tolerance. However, our data also hint towards rather low endogenous tumor cell processing and presentation of MDPs in the context of HLA-A2.1 molecules. Consequently, we conclude that MDR and MRP proteins must be considered as weak tumor specific antigens-at least for colorectal carcinoma. Their direct contribution to therapy-failure implies however, that it is worth to further pursue this approach.
BMC Immunology 07/2011; 12:38. · 2.53 Impact Factor
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ABSTRACT: Partial ligation of portal branches leads to atrophy of the deprived lobes and hypertrophy of the intact lobes. In this study we investigated the microcirculatory response and their consequences on tissue regeneration after left-sided portal branch ligation (PBL) in Sprague-Dawley rats. At day 1 and 3 after PBL the hepatic microcirculation was assessed by intravital microscopy (IVM). In addition histological, immunohistochemical and biochemical techniques were used to determine alterations of hepatic microarchitecture. IVM analysis of the microcirculation of the ligated hepatic lobes revealed significant alterations with a reduction in sinusoidal perfusion rate, a decrease of red blood cell velocity, an increase of sinusoidal diameter and a marked reduction in shear stress at days 1 and 3 after PBL. On the contrary, the non-ligated lobes presented with higher blood flow velocities, marked sinusoidal vasoconstriction and thus, shear stress elevation. In consequence, ligated liver lobes exhibited marked cell apoptosis and necrosis, being accompanied by massive intrahepatic leukocyte accumulation and a ~30% weight loss. The non-ligated liver tissue showed marked PCNA expression and thereby completely compensated weight loss. Beside full restoration of liver mass, sinusoidal blood flow was comparable in ligated and non-ligated lobes as well as in sham-treated controls. This study shows that the liver aims at constant tissue mass and blood flow, most probably for maintenance of adequate clearance function. In addition, it supports the hypothesis that shear stress plays a pivotal role in triggering liver hypertrophy in the non-ligated lobes.
Microvascular Research 03/2011; 81(3):274-80. · 2.83 Impact Factor
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Jolanta Majcher-Peszynska,
Marko Sass,
Sora Schipper,
Viktor Czaika,
Andreas Gussmann,
Ralf Lobmann,
Ralf G Mundkowski,
Christoph Luebbert,
Peter Kujath,
Bernhard R Ruf,
Horst Koch,
Wolfgang Schareck, Ernst Klar,
Bernd Drewelow
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ABSTRACT: Physiological changes occurring in patients with diabetes may affect the pharmacokinetics and penetration of antimicrobial agents into peripheral tissue. We examined the pharmacokinetics and the penetration of moxifloxacin into perinecrotic tissue of diabetic foot lesions in patients with diabetic foot infections (DFI).
Adult patients suffering from type 2 diabetes mellitus and hospitalized for DFI (Texas classification of at least B2) were treated with 400 mg moxifloxacin intravenously (IV) or orally (PO) once daily. The pharmacokinetics of moxifloxacin and its concentration 3 h after administration in samples of perinecrotic tissue resected from infected diabetic foot wounds were determined at steady state (days 4-8).
A total of 53 patients with diabetes mellitus type 2 (mean age 69.4 ± 10.8 years) were included in the study, of whom 28 received PO and 25 IV moxifloxacin therapy for a median of 8 days. In the PO and IV subgroups, the mean maximum observed plasma concentration (C (max)) in plasma was 2.69 and 4.77 mg/l at a median of 2 [time to reach C (max) (T (max)) range 1.0-8.0 h] and 1 h after administration, respectively. A mean area under the plasma concentration-time curve from time 0 until the last quantifiable plasma concentration (AUC(0-24 h)) of 29.36 mg h/l (PO) and 27.09 mg h/l (IV) was achieved. Mean moxifloxacin concentrations in perinecrotic tissue of infected diabetic foot wounds following PO or IV administration were 1.79 ± 0.82 and 2.20 ± 1.54 μg/g, thus exceeding the MIC(90) (minimum inhibitory concentration required to inhibit growth of 90% of organisms) for Staphylococcus aureus (0.25 mg/l) by seven- and eightfold and the MIC(90) for Escherichia coli (0.06 mg/l) by 29-fold and 36-fold, respectively. The mean tissue-to-plasma ratios of moxifloxacin concentration 3 h after administration were 1.01 ± 0.57 (PO) and 1.09 ± 0.69 (IV). Significant differences between the routes of administration were observed for T (max) and C (max) (P < 0.01), but not for other clinically relevant parameters (AUC(0-24); moxifloxacin DFI tissue concentration).
The plasma concentration-time curve of moxifloxacin in diabetic patients is similar to that of healthy volunteers. We also observed a good penetration of moxifloxacin into inflamed DFI tissue which taken together with the possibility of sequential IV/PO therapy suggest that moxifloxacin 400 mg once daily is a therapeutic option in the treatment of DFI caused by susceptible organisms.
European Journal of Clinical Pharmacology 02/2011; 67(2):135-42. · 2.85 Impact Factor
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ABSTRACT: Ischemic preconditioning (IP) and intermittent clamping (IC) increase the ischemic tolerance of the liver. The underlying mechanisms are not completely understood. Heat shock proteins protect cellular integrity in stress and have been discussed as mediators in preconditioning. IP and IC in rat livers were compared with respect to HSP induction and postischemic microcirculation.
All animals were exposed to 70min of partial warm liver ischemia. Different clamping protocols were used: in control animals (C) 70min continuous ischemia was applied. IP was performed by 5min ischemia and 10min reperfusion before the 70min ischemia time. In IC-groups, ischemia time of 70min was divided into four intervals. Each group included 21 animals with 3 different reperfusion intervals; either 30min, 12 or 36h. Intravital microscopy was performed after 30min of reperfusion. AST-levels and HSP induction were analysed 90min, 12 and 36h after reperfusion.
IP and IC significantly improved sinusoidal perfusion (IP: 83.4±2.8%; IC: 84.4±4.6% vs. C: 60.4±3.9%; p<0.001) and leucocyte adherence in sinusoids (IP: 51.9±12.0, IC: 40.9±4.7 vs. C: 90.1±17.7/mm(2) liver surface; p<0.001) and postsinusoidal venules. AST-levels were minimized in IP and IC compared to controls (12h after reperfusion: IP: 969±934U/l, IC: 675±562U/l vs. C: 2373±792U/l; p=0.004). In the course of reperfusion HSP70 protein expression doubled between 90min and 12h in IC (0.529±0.227 vs. 0.992±0.246; p<0.05) and control-groups (0.572±0.314 vs. 1.106±0.309; p<0.05) whereas it remained unchanged in the IP-group (0.437±0.383 vs. 0.412±0.439; n.s.).
Microcirculation is similarly preserved by IP and IC. The early protection derived by IP prevents further induction of HSP70 in opposite to IC. Therefore, IP may offer a more comprehensive protection against I/R on a cellular and transcriptional level.
Microvascular Research 12/2010; 80(3):365-71. · 2.83 Impact Factor
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ABSTRACT: Renal artery entrapment by the diaphragmatic crus is a very infrequent cause of renovascular hypertension. We present the case of a young man who was assigned to our hospital with arterial hypertension and stenosis of the left renal artery. Extrinsic compression was diagnosed by duplex ultrasound and magnetic resonance angiography. We performed laparoscopic decompression using the transperitoneal retrorenal approach. Antihypertensive medication could be stopped thereafter and duplex ultrasound revealed a normal blood flow to the left renal artery. We therefore propose laparoscopic treatment of left renal artery entrapment as a minimally-invasive alternative to open surgery.
Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 11/2010; 52(5):1357-61. · 3.52 Impact Factor
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ABSTRACT: To investigate the effectiveness of Clostridium novyi (C. novyi)-NT spores for the treatment of established subcutaneous pancreatic tumor in the syngeneic, immunocompetent Panc02/C57Bl/6 model.
C. novyi-NT spores were applied intravenously to animals carrying established pancreatic tumors of three different sizes. Systemic immune responses in peripheral blood and spleen were examined by flow cytometry. Supplementary, cytotoxic activity of lymphocytes against syngeneic tumor targets was analyzed.
Application of spores identified, that (1) small tumors (< 150 mm(3)) were completely unaffected (n = 10); (2) very large tumors (> 450 mm(3)) responded with substantial necrosis followed by shrinkage and significant lethality most likely due to tumor lysis syndrome (n = 6); and (3) an optimal treatment window exists for tumors of approximately 250 mm(3) (n = 21). In this latter group, all tumor-bearing animals had complete tumor regression and remained free of tumor recurrence. In subsequent tumor rechallenge experiments a significant delay in tumor growth compared to the initial tumor cell inoculation was observed (tumor volume at day 28: 197.8 +/- 87.3 mm(3) vs 500.1 +/- 50.9 mm(3), P < 0.05). These effects were accompanied by systemic activation of immune response mechanisms predominantly mediated by the innate arm of the immune system.
The observed complete tumor regression is encouraging and shows that immunotherapy with C. novyi-NT is an interesting strategy for the treatment of pancreatic carcinomas of defined sizes.
World Journal of Gastroenterology 07/2010; 16(28):3546-52. · 2.47 Impact Factor
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ABSTRACT: The induction of potent T cell responses against tumors is the goal of tumor immunotherapy. One approach is the fusion of antigen-presenting cells (APCs) with tumor cells. Hybrid cells combine the antigenicity of tumors with the immunostimulatory capacity of APCs. However, contaminating unfused cells present in the fusion reaction may prevent the induction of antitumoral immune responses. Here, we present a simple and effective protocol to substantially elevate the purity of hybrid cells.
Colorectal tumor cell lines and CD40-activated B cells as APCs were fused using polyethylene glycol. Important parameters including cell numbers, concentrations, and handling and detection procedures were optimized. Combination of these optimized fusion conditions with both magnetic cell sorting and selective adherence delivered very pure preparations of APC/tumor cell hybrids. The T cell stimulatory capacity of these hybrids was tested using ELISpot.
The optimization of the fusion resulted in maximal fusion efficiencies of 31.6% (n = 10, range 13.5-46.6%). Prelabeling of APCs with magnetic beads allowed for easy elimination of up to 94.3% of unfused tumor cells from the cell mixture by magnetic separation. Hybrid cell capacity to firmly adhere to plastic was then used to remove unfused B cells from the remaining cell mixture by simple washing. The obtained 85.0% pure hybrids cells readily induced antitumoral T cell responses.
Our protocol delivers pure hybrid cell preparations with strong immunostimulatory potential. In subsequent experiments, the ability of hybrid cells to stimulate specific antitumoral T cell responses must be tested in vivo.
Langenbeck s Archives of Surgery 03/2010; 395(4):365-71. · 1.81 Impact Factor
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ABSTRACT: Although hepatic ischemia-reperfusion (I/R) injury has been investigated for more than two decades, histopathological documentation is limited. As a result, three pig livers with I/R injury and three control livers were injected with colored media, cut into 14 segments, and examined by light microscopy together with microscopic map making. In livers with I/R injury, lobules were identified as being occluded or unoccluded. The proportion of the occluded lobules increased in a caudocephalic fashion, while that of the unoccluded lobules decreased (chi(2) for linear trend, P<0.0001). Especially in the occluded lobules, swollen hepatic plates displayed various forms of cellular distortion. Collapsed sinusoids containing leukocyte aggregation and shrunken central veins were observed together with reduced caliber of the contiguous sublobular veins. Portal vein constriction with loosening of the surrounding stroma suggestive of edema and hepatic artery dilation were also seen. Isolated arterioles and transintimal vasal outlets of the hepatic vein's vasa venarum were dilated and frequently observed. In conclusion, I/R injury affected the liver parenchyma, the microvasculature, and its surrounding stroma. The heterogeneous distribution of occluded and unoccluded lobules is suggested due to the difference of vascular structure in various liver segments. The constrictive/obstructive changes in the portosinusoidal-hepatic vascular profile suggest a definite increase in resistance at presinusoidal, sinusoidal, and proximal postsinusoidal levels, resulting in an expansion of the arterial shunt circulation.
Microvascular Research 02/2010; 80(1):123-32. · 2.83 Impact Factor
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ABSTRACT: Molecular heterogeneity of colorectal carcinoma (CRC) is well recognized, forming the rationale for molecular tests required before administration of some of the novel targeted therapies that now are rapidly entering the clinics. For clinical research at least, but possibly even for future individualized tumor treatment on a routine basis, propagation of patients' CRC tissue may be highly desirable for detailed molecular, biochemical or functional analyses. However, complex logistics requiring close liaison between surgery, pathology, laboratory researchers and animal care facilities are a major drawback in this. We here describe and evaluate a very simple cryopreservation procedure for colorectal carcinoma tissue prior to xenografting that will considerably reduce this logistic complexity.
Fourty-eight CRC collected ad hoc were xenografted subcutaneously into immunodeficient mice either fresh from surgery (N = 23) or after cryopreservation (N = 31; up to 643 days).
Take rates after cryopreservation were satisfactory (71%) though somewhat lower than with tumor tissues fresh from surgery (74%), but this difference was not statistically significant. Re-transplantation of cryopreserved established xenografts (N = 11) was always successful. Of note, in this series, all of the major molecular types of CRC were xenografted successfully, even after cryopreservation.
Our procedure facilitates collection, long-time storage and propagation of clinical CRC specimens (even from different centres) for (pre)clinical studies of novel therapies or for basic research.
BMC Cancer 01/2010; 10:362. · 3.01 Impact Factor
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ABSTRACT: Microsatellite instability (MSI-H) induced by defects of the DNA mismatch repair system results in insertion or deletion of single nucleotides at short repetitive DNA sequences. About 15% of sporadic and approximately 90% of hereditary nonpolyposis colorectal cancers display MSI-H. When affecting coding regions, MSI-H results in frameshift mutations and expression of corresponding frameshift peptides (FSPs). Functional tumor promoting relevance has been demonstrated for a growing number of genes frequently hit by MSI-H. Contrary, immune reactions against FSPs are involved in the immune surveillance of MSI-H cancers. Here, we provide conclusive data that the (-1) frame of U79260(FTO) encodes an HLA-A0201-restricted cytotoxic T cell epitope (FSP11; TLSPGWSAV). T cells specific for FSP11 efficiently recognized HLA-A0201((pos)) tumor cells harboring the mutated reading frame. Considering the exceptionally high mutation rate of U79260(FTO) in MSI-H colorectal carcinoma (81.8%), this recommends that FSP11 be a component of future vaccines.
Journal of Biomedicine and Biotechnology 01/2010; 2010:841451. · 2.44 Impact Factor
