A Prospective, Phase I/II, Open-Label Pilot Trial to Assess the Safety of Hyperthermic Intraperitoneal Chemotherapy After Oncological Resection of Pancreatic Adenocarcinoma.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a common fatal disease with unfavorable prognosis, even after oncological resection. To improve survival, adding hyperthermic intraperitoneal chemotherapy (HIPEC) has been suggested. Whether HIPEC entails disproportional short-term mortality is unknown and a prospectively determined adverse events profile is lacking. Since both pancreatic resection and HIPEC may relevantly influence morbidity and mortality, this uncontrolled single-arm, open-label, phase I/II pilot trial was designed to assess the 30-day mortality rate, treatment feasibility, and adverse events connected with HIPEC after oncological pancreatic surgery. METHODS: This trial recruited patients scheduled for PDAC resection. A sample size of 16 patients receiving study interventions was estimated to establish a predefined margin of treatment-associated short-term mortality with a power of > 80%. Patients achieving complete macroscopic resection received HIPEC with gemcitabine administered at 1000 mg/m2 body surface area heated to 42 °C for 1 hour. RESULTS: Within 30 days after intervention, no patient died or experienced any adverse events higher than grade 3 that were related to HIPEC. Furthermore, treatment-related adverse events were prospectively documented and categorized as expected or unexpected. This trial supports that the actual mortality rate after PDAC resection and HIPEC is below 10%. HIPEC treatment proved feasible in 89% of patients allocated to intervention. Pancreatic fistulas, as key complications after pancreas surgery, occurred in 3/13 patients under risk. CONCLUSION: Combined pancreas resection and gemcitabine HIPEC proved feasible and safe, with acceptable morbidity and mortality. Based on these results, further clinical evaluation can be justified. REGISTRATION NUMBER: NCT02863471 ( http://www.clinicaltrials.gov ).

Pancreatoduodenectomy with or without prophylactic falciform ligament wrap around the hepatic artery for prevention of postpancreatectomy haemorrhage: randomized clinical trial (PANDA trial).

BACKGROUND: Postpancreatectomy haemorrhage (PPH) is a rare but potentially fatal complication after pancreatoduodenectomy. Preventive strategies are lacking with scarce data for support. The aim of this study was to investigate whether a prophylactic falciform ligament wrap around the hepatic and gastroduodenal artery can prevent PPH from these vessels. METHODS: In a randomized, controlled, multicentre trial, patients who were scheduled for elective open partial pancreatoduodenectomy with pancreatojejunostomy between 5 November 2015 and 2 April 2020 were randomly allocated in a 1 : 1 ratio to undergo pancreatoduodenectomy with (intervention) or without (control) a falciform ligament wrap around the hepatic artery. The primary endpoint was the rate of clinically relevant PPH from the hepatic artery or gastroduodenal artery stump within 3 months after pancreatoduodenectomy. Secondary endpoints were the rates of associated postoperative complications, for example postoperative pancreatic fistula (POPF) and PPH. RESULTS: Altogether, 445 patients were randomized with 222 and 223 in each group. Among the patients included in modified intention-to-treat analysis (207 in the intervention group and 210 in the control group), the primary endpoint was observed in six of 207 in the intervention group compared with 15 of 210 in the control group (2.9 versus 7.1 per cent respectively; odds ratio 0.39 (95 per cent c.i. 0.15 to 1.02); P = 0.071). Per protocol analysis showed a significant reduction in the intervention group (odds ratio 0.26 (95 per cent c.i. 0.09 to 0.80); P = 0.017). A soft pancreas texture (43 per cent) and the rate of a clinically relevant POPF were evenly (20 per cent) distributed between the groups. The rate of any clinically relevant PPH including the primary endpoint and other bleeding sites was not significantly different between intervention and control groups (9.7 versus 14.8 per cent respectively). CONCLUSION: A falciform ligament wrap may reduce PPH from the hepatic artery or gastroduodenal artery stump and should be considered during pancreatoduodenectomy. REGISTRATION NUMBER: NCT02588066 (http://www.clinicaltrials.gov).

Peritoneal metastasis in gastric cancer: results from the German database.

BACKGROUND: Patients with peritoneal metastases of gastric cancer have a poor prognosis with a median survival of 7 months. A benefit of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) could be shown in several selected patient cohorts but remains controversial. The aim of this study was, to reflect the results of a national German HIPEC registry initiated by the German Society of General and Visceral Surgery (DGAV). METHODS: The DGAV HIPEC registry StuDoQ|Peritoneum documents patients with peritoneal malignancy contributed from 52 hospitals. All consecutive documented patients from 2011 until 2016 (n = 3078) were treated with CRS and HIPEC and were analysed. A total of 315 (10%) suffered from gastric cancer and were analysed. RESULTS: A complete data set of 235 patients was available for this study, including 113 male (48.1%) and 122 female (51.9%) patients with a median age of 53.4 years (SD ± 11.9). The median PCI was 8.0 (range 1-30). A complete cytoreduction was achieved in 121 patients (71.6%). Postoperative complications (Clavien-Dindo grades 3-4) occurred in 40 patients (17%). The median overall survival (OS) time was 13 months. The 5-year survival rate was 6%. According to the PCI from 0-6 (n = 74); 7-15 (n = 70) and 16-39 (n = 24) the median OS differs significantly (18 months vs. 12 months vs. 5 months; p = 0.002). CONCLUSIONS: CRS and HIPEC in selected patients with gastric cancer and peritoneal spread can improve survival when they are treated in centers. An accurate staging and patient selection are of major importance to achieve long-term survival.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy: A safe treatment option for intraperitoneal rhabdomyosarcoma in children below 5 years of age.

Advanced and relapsed intraperitoneal rhabdomyosarcomas in young children represent an oncological challenge and options for local tumor control are limited. Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is commonly used in advanced peritoneal tumors in adults. However, no studies are available regarding CRS and HIPEC in young children. We report our experiences treating six patients with intraperitoneal rhabdomyosarcoma with CRS and HIPEC using cisplatin and doxorubicin focusing on safety and outcomes. No procedure-associated mortalities occurred and no major short- or long-term toxicities were recorded. All patients showed no evidence of disease after 12-month median (7-41) follow-up.

First case report of malignant peritoneal mesothelioma and oral verrucous carcinoma in a patient with a germline PTEN mutation: a combination of extremely rare diseases with probable further implications.

BACKGROUND: The PTEN-hamartoma-tumor-syndrome (PHTS) is caused by germline mutations in Phosphatase and Tensin homolog (PTEN) and predisposes to the development of several typical malignancies. Whereas PTEN mutations have been implicated in the occurrence of malignant mesotheliomas, the genetic landscape of verrucous carcinomas (VC) is largely uncharted. Both VC and malignant peritoneal mesotheliomas (MPM) are exceedingly rare and a potential link between these malignancies and PHTS has never been reported. CASE PRESENTATION: We here describe the clinical course of a PHTS patient who, in addition to a typical thyroid carcinoma at the age of 36 years, developed a highly-differentiated oral VC and an epithelioid MPM six years later. The patient with a history of occupational asbestos exposure underwent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for MPM. The clinical diagnosis of PHTS was consequently corroborated by a germline PTEN deletion. Sequencing of tumor tissue revealed a second hit in PTEN in the thyroid carcinoma and VC, confirmed by a PTEN loss and activation of the PI3K/AKT pathway in immunohistochemistry. Furthermore, additional somatic mutations in the thyroid carcinoma as well as in the VC were detected, whereas the genetics of MPM remained unrevealing. DISCUSSION AND CONCLUSIONS: We here report the very unusual clinical course of a patient with rare tumors that have a germline mutation first hit in PTEN in common. Since this patient was exposed to asbestos and current evidence suggests molecular mechanisms that might render PHTS patients particularly susceptible to mesothelioma, we strongly recommend PHTS patients to avoid even minimal exposure.

Pharmacodynamics of Oxaliplatin-Derived Platinum Compounds During Hyperthermic Intraperitoneal Chemotherapy (HIPEC): An Emerging Aspect Supporting the Rational Design of Treatment Protocols.

BACKGROUND: Hyperthermic intraperitoneal chemotherapy (HIPEC) is used to treat peritoneal surface malignancies with application of cytostatic drugs such as oxaliplatin (OX) after cytoreductive surgery. Despite its increased use, evidence for optimal drug dosage, and notably duration of HIPEC, is scarce. METHODS: In this study, OX distribution was comprehensively assessed in nine patients during HIPEC (300 mg OX/m2 body surface area in Physioneal solution for 30 min). Oxaliplatin and its derivatives were measured in peritoneal perfusates over time by liquid chromatography coupled with mass spectrometry (LC-MS), and the resulting total platinum concentration in tissue was analyzed by atomic absorption spectrometry. Additionally, a novel impedance-based real-time cytotoxicity assay was used to evaluate the bioactivity of perfusates ex vivo. RESULTS: Compared with amounts of OX expected in peritoneal perfusates by calculation, only 10-15% of the parent drug could be detected by LC-MS during HIPEC. Notably, the study additionally detected platinum compounds consistent with OX transformation, accounting for a further fraction of the applied drug. The cytotoxic properties of perfusates remained unchanged during HIPEC, with only a slight but significant attenuation evidenced after 30 min. CONCLUSIONS: The bioactivity of peritoneal perfusates ex vivo is a useful parameter for evaluating the actual cytotoxic potential of OX and its derivatives used in HIPEC over time, overcoming important limitations and disadvantages associated with respective drug monitoring only. Ex vivo cytotoxicity assays may be a promising tool to aid guiding future standardization and harmonization of HIPEC protocols based on drug-mediated effects.

Overall morbidity but not mortality is increased in elderly patients following cytoreductive surgery and HIPEC.

BACKGROUND: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) prolongs survival in selected patients with peritoneal metastases. Since this procedure is likely to be associated with increased morbidity and mortality, it remains controversial whether it is also suitable for patients older than 70 years. METHODS: Consecutive patients with radiographic evidence of peritoneal metastases (PM) were scheduled for CRS and HIPEC at the Comprehensive Cancer Center, University Hospital Tübingen, Germany. Clinical data were retrospectively analyzed categorizing patients with respect to age into elderly (age ≥ 70) and non-elderly patients (age < 70). RESULTS: Between June 2005 and March 2014, 381 patients with a median age of 55 [14-77] years could be enrolled with 29 patients (8 %) being at least 70 years old. Both groups were comparable for tumor-related parameters including PCI, CC-status, time in operating room, and visceral resections. However, there was a difference in patient-related factors such as cardio-pulmonary comorbidities and ASA score. We found no difference in overall and recurrence-free survival between the two groups. Surgery-related mortality was 0.9 % in patients younger than 70 years whereas no patient died in the elderly group. Overall morbidity was 47 % in the younger and 76 % in the elderly group (p = 0.048). There was no difference in Clavien-Dindo grade III-IV morbidity. Logistic regression analysis proved age as an independent risk factor for increased overall morbidity in elderly patients. CONCLUSION: In elderly patients, CRS and HIPEC are associated with increased overall morbidity but neither Dindo III-IV morbidity nor surgery-related mortality.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in recurrent epithelial ovarian cancer with peritoneal metastases: a single centre experience.

BACKGROUND: This investigation aims to assess morbidity, mortality and postoperative outcomes of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in recurrent epithelial ovarian cancer (REOC) with peritoneal metastases (PM). METHODS: Consecutive patients with radiographic evidence of REOC with PM were scheduled for CRS and HIPEC at the Comprehensive Cancer Center, University Hospital Tübingen, Germany. Clinical data were retrospectively analyzed. RESULTS: In total, 90 patients were analyzed. Complete cytoreduction and HIPEC could be performed in 69 % of patients. When categorizing patients with respect to the completeness of cytoreduction (CC-0/1 vs CC-2/3), there was no difference considering baseline demographic characteristics. Cumulative morbidity was 42 %. Morbidity rates did not statistically differ between CC-0/1 patients with HIPEC and CC-2/3 patients without HIPEC. No surgery-related and 90-day postoperative mortality was observed. In CC-0/1 patients, median overall survival was 35 months as opposed to 14 months in CC-2/3 patients. There was no difference in survival with respect to the peritoneal carcinomatosis index (PCI) as long as complete cytoreduction could be achieved. CONCLUSIONS: CRS and HIPEC can be performed with acceptable morbidity and low mortality in specialized centres. Our data do not suggest that HIPEC necessarily increases the risk of postoperative adverse events.

Do patient- and tumor-related factors predict the peritoneal spread of pancreatic adenocarcinoma?

PURPOSE: In pancreatic cancer, the presence of peritoneal carcinomatosis (PC) precludes the possibility of a surgical cure, irrespective of the resectability of the primary tumor. However, peritoneal spread cannot be reliably detected radiographically during preoperative tumor staging. METHODS: The pancreatic adenocarcinoma database of the Tübingen Comprehensive Cancer Center included 29 patients in whom PC was incidentally detected during the surgery. These patients were retrospectively compared for patient- and tumor-related factors with 29 randomly selected patients without PC who underwent curative resection. RESULTS: Clinical jaundice and diarrhea were more frequently present in patients without PC. The CA 19-9 levels were significantly higher in patients with PC compared to those in patients without PC. No other differences were observed in the patient- or tumor-related factors between the two groups. CONCLUSION: In pancreatic cancer patients, markedly elevated CA 19-9 levels may serve as surrogate marker for peritoneal dissemination, irrespective of the local resectability of the tumor. In such patients, laparoscopy should be considered as an additional staging tool to rule out peritoneal carcinomatosis.

Fluorescence-Guided Laparoscopy after Oral Hypericin Administration for Staging of Locally Advanced Gastric Cancer-A Pilot Study.

(1) Background: Laparoscopic staging is essential in gastric cancer (GC) to rule out peritoneal metastasis (PM). Hypericin, a plant-derived fluorescent compound, has been suggested to improve laparoscopic visualization of PM from GC. This prospective, single-arm, open-label clinical trial aimed to assess the feasibility and safety of oral hypericin administration as well as the suitability of fluorescence-guided laparoscopy (FGL) for improving the sensitivity and specificity of staging in GC patients (EudraCT-Number: 2015-005277-21; clinicaltrials.gov identifier: NCT-02840331). (2) Methods: GC patients received Laif® 900, an approved hypericin-containing phytopharmaceutical, once orally two to four hours before white light and ultraviolet light laparoscopy. The peritoneal cancer index was evaluated, biopsies taken and hypericin concentrations in serum and peritoneal tissue were determined by mass spectrometry. (3) Results: Between 2017 and 2021, out of 63 patients screened for eligibility, 50 patients were enrolled and treated per protocol. The study intervention was shown to be feasible and safe in all patients. Standard laparoscopy revealed suspicious lesions in 27 patients (54%), among whom 16 (59%) were diagnosed with PM. FGL identified suspicious areas in 25 patients (50%), among whom PM was confirmed in 13 cases (52%). Although hypericin concentrations in serum reached up to 5.64 ng/mL, no hypericin was detectable in peritoneal tissue biopsies. (4) Conclusions: FGL in patients with GC was shown to be feasible but futile in this study. Sufficient levels of hypericin should be ensured in target tissue prior to reassessing FGL with hypericin.

Risk factors for recurrence following complete cytoreductive surgery and HIPEC in colorectal cancer-derived peritoneal surface malignancies.

PURPOSE: Recurrent disease following complete cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is a relevant clinical scenario. We aimed to determine risk factors for recurrence. METHODS: Prospectively collected data of patients enrolled in the Peritoneal Surface Malignancy Program at the University of Tübingen between 2005 and 2011 were retrospectively analyzed. All patients were treated by standardized CRS and HIPEC. Recurrence was defined either radiographically by CT, PET-CT scan, or reoperation. RESULTS: Fifty-two patients received complete CRS (CC-0/CC-1) and HIPEC. Median time to recurrence was 229 days (103-1,028). Overall recurrence rate within follow-up was 48 %. Of patients with recurrent disease, 44 % experienced extraperitoneal systemic tumor spread. In multivariate analysis, grading of ≥ 3 was shown as an independent risk factor for recurrent disease, while a trend was observed for maximal tumor load in the upper abdominal region. Clinical parameters did not show an impact on recurrence. CONCLUSIONS: Primary tumor grading seems to be an independent risk factor for recurrence following complete CRS and HIPEC in colorectal cancer-derived peritoneal surface malignancies.

Impact of endotoxin exposure after exhausting exercise on the immune system in solid organ transplant recipients.

Subsequent to prolonged exhausting exercise a transient immunosuppression is often observed in athletes. This so-called "open window" results in a reduced resistance of the athletes to viral and bacterial infections after an exhaustive exercise bout. Concerning the effect of bacterial endotoxin contact after exhausting exercise in transplant recipients, who are innately immunosuppressed by their medication, no data exists at present. After performing 81 km cycling, including ascending more than 1800 m in altitude, peripheral blood from 10 male kidney transplant recipients and from 10 healthy controls matched for age and gender was obtained. Simulating contact of the athletes with a pathogen post-exercise, the blood samples were incubated with Lipopolysaccharides (LPS). Thereafter microarray analysis was performed. Microarray analysis revealed a markedly oppositional pattern of gene expression in transplant recipients compared with their controls after LPS incubation. Especially immune response genes were significantly over-represented in controls immediately after the exhaustive exercise bout with LPS stimulation, whereas numerous apoptotic genes were over-represented in transplant recipients. Merging our previous data with these recent findings it should be discussed if transplant recipients need to reduce their immunosuppressive medication before performing exhaustive exercise.

Prolonged Exposure to Oxaliplatin during HIPEC Improves Effectiveness in a Preclinical Micrometastasis Model.

Cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (HIPEC) was considered a promising treatment for patients with peritoneal metastasis from colorectal cancer. However, the recently published randomized controlled PRODIGE 7 trial failed to demonstrate survival benefits through the addition of short-term oxaliplatin-based HIPEC. Constituting a complex multifactorial treatment, we investigated HIPEC in a preclinical model concerning the elimination of minimal tumor residues, thereby aiming to better understand the size of effects and respective clinical trial results. Patient samples of peritoneal perfusates obtained during HIPEC treatments and oxaliplatin-containing solutions at clinically relevant dosages, conforming with established HIPEC protocols, were assessed regarding their ability to eliminate modelled ~100 µm thickness cancer cell layers. Impedance-based real-time cell analysis and classical end-point assays were used. Flow cytometry was employed to determine the effect of different HIPEC drug solvents on tumor cell properties. Effectiveness of peritoneal perfusate patient samples and defined oxaliplatin-containing solutions proved limited but reproducible. HIPEC simulations for 30 min reduced the normalized cell index below 50% with peritoneal perfusates from merely 3 out of 9 patients within 72 h, indicating full-thickness cytotoxic effects. Instead, prolonging HIPEC to 1 h enhanced these effects and comprised 7 patients' samples, while continuous drug exposure invariably resulted in complete cell death. Further, frequently used drug diluents caused approximately 25% cell size reduction within 30 min. Prolonging oxaliplatin exposure improved effectiveness of HIPEC to eliminate micrometastases in our preclinical model. Accordingly, insufficient penetration depth, short exposure time, and the physicochemical impact of drug solvents may constitute critical factors.

Everolimus interferes with the inflammatory phase of healing in experimental colonic anastomoses.

BACKGROUND: Delayed wound healing is a serious side effect of mTOR inhibitor-based immunosuppression after solid organ transplantation. The aim of this study was to test the hypothesis that the mTOR inhibitor everolimus interferes with the inflammatory phase of healing in experimental colonic anastomoses. MATERIALS AND METHODS: Thirty male Sprague-Dawley rats received a colonic anastomosis. Then, animals were randomized to three groups of daily treatment with either vehicle or everolimus in two different dosages (1.0mg/kg or 3.0mg/kg). After 7 d, rats were sacrificed, and mechanical, histologic, and biochemical parameters of intestinal healing were assessed. RESULTS: Anastomotic bursting pressure was significantly decreased by everolimus in both dosages, whereas hydroxyproline content was reduced only by the high everolimus dosage. Everolimus diminished cellular proliferation and new vessel growth. Furthermore, both quantity as well as quality of newly synthesized collagen fibers in the anastomotic granulation tissue was reduced. On the other hand, myeloperoxidase-positive (MPO) cells and interleukin-6 (IL-6) concentrations were increased, as was the activity of matrix-metalloproteinases MMP-2 and MMP-9. CONCLUSION: Everolimus interferes with the inflammatory phase of healing. However, it remains unclear whether this phenomenon is involved in everolimus impairment of experimental anastomotic repair.

Cytoreductive surgery and HIPEC in peritoneal recurrent ovarian cancer: experience and lessons learned.

PURPOSE: Peritoneal recurrence of ovarian cancer is frequent after primary surgery and chemotherapy and has poor long-term survival. De novo cytoreductive surgery is crucial with the potential to improve prognosis, especially when combined with hyperthermic intraperitoneal chemotherapy (HIPEC). METHODS: The sampled data of 40 consecutive patients were retrospectively analyzed. Thirty-one patients were treated with cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy. RESULTS: No patient was lost in the perioperative period, and the combined procedure was performed with acceptable morbidity. Colon-preserving cytoreductive surgery was associated with reduced morbidity. CONCLUSIONS: Patients suffering from peritoneal recurrence of ovarian cancer should be considered for radical reoperation with HIPEC in a center with expertise in multimodal therapeutic options. Organ-preserving cytoreductive surgery allows complete cytoreduction with the goal of decreasing morbidity.

Twelve-Year Single Center Experience Shows Safe Implementation of Developed Peritoneal Surface Malignancy Treatment Protocols for Gastrointestinal and Gynecological Primary Tumors.

(1) Background: Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy provide survival benefits to selected patients. We aimed to report our experience and the evolution of our peritoneal surface malignancy program. (2) Methods: From June 2005 to June 2017, 399 patients who underwent cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy at the Tübingen University Hospital were analyzed from a prospectively collected database. (3) Results: Peritoneal metastasis from colorectal cancer was the leading indication (group 1: 28%; group 2: 32%). The median PCI was 15.5 (range, 1-39) in group 1 and 11 (range, 1-39) in group 2 (p = 0.002). Regarding the completeness of cytoreduction (CC), a score of 0 was achieved in 63% vs. 69% for group 1 and 2, respectively (p = 0.010). Median overall survival rates for patients in group 1 and 2 for colon cancer, ovarian cancer, gastric cancer and appendix cancer were 34 and 25 months; 45 months and not reached; 30 and 16 months; 39 months and not reached, respectively. The occurrence of grade-III and -IV complications slightly differed between groups (14.5% vs. 15.6%). No 30-day mortality occurred. (4) Conclusions: Specialized centers are able to provide low-morbidity cytoreductive surgery and hyperthermic intraperitoneal chemotherapy without mortality. Strict patient selection during the time period significantly improved CC scores.

Phosphoglycerate kinase 1 a promoting enzyme for peritoneal dissemination in gastric cancer.

Peritoneal carcinomatosis is a frequent finding in gastric cancer associated with a poor prognosis. The features that enable gastric tumors to disseminate are poorly understood until now. Previously, we showed elevated mRNA levels of phosphoglycerate kinase 1 (PGK1), an adenosine triphosphate-generating enzyme in the glycolytic pathway, the chemokine receptor 4 (CXCR4), the corresponding chemokine ligand 12 (CXCL12) and beta-catenin in specimens from gastric cancer patients with peritoneal carcinomatosis. In this study, the influence of PGK1 on CXCR4 and beta-catenin was assessed as well as the invasiveness of PGK1 overexpressing cancer cells. In this current study, we found that PGK1 regulates the expression of CXCR4 and beta-catenin at the mRNA and protein levels. On the other hand, CXCR4 regulates the expression of PGK1. Plasmid-mediated overexpression of PGK1 dramatically increased the invasiveness of gastric cancer cells. Interestingly, inhibition of CXCR4 in cells overexpressing PGK1 produced only a moderate reduction of invasiveness suggesting that, PGK1 itself has a critical role in tumor invasiveness. Immunohistochemistry in specimens from diffuse gastric cancer patients also revealed an overexpression of PGK1 in patients with development of peritoneal carcinomatosis. Therefore, PGK1 may be a crucial enzyme in peritoneal dissemination. Together these findings suggest that the enhanced expression of PGK1 and its signaling targets CXCR4 and beta-catenin in gastric cancer cells promote peritoneal carcinomatosis. Thus, PGK1 may serve as prognostic marker and/or be a potential therapeutic target to prevent dissemination of gastric carcinoma cells into the peritoneum.

Circadian expression of clock- and tumor suppressor genes in human oral mucosa.

PURPOSE: Circadian rhythms are daily oscillations of multiple biological processes driven by endogenous clocks. Imbalance of these rhythms has been associated with cancerogenesis in humans. To further elucidate the role circadian clocks have in cellular growth control, tumor suppression and cancer treatment, it is revealing to know how clock genes and clock-controlled genes are regulated in healthy humans. MATERIALS AND METHODS: Therefore comparative microarray analyses were conducted investigating the relative mRNA expression of clock genes throughout a 24-hour period in cell samples obtained from oral mucosa of eight healthy diurnally active male study participants. Differentially expressed selected genes of interest were additionally evaluated using qRT-PCR. RESULTS: Microarray analysis revealed 33 significant differentially regulated clock genes and clock- controlled genes, throughout a one day period (6.00h, 12.00h, 18.00h, 24.00h). Hereof were 16 clock genes and 17 clock- controlled genes including tumor suppressor- and oncogenes. qRT-PCR of selected genes of interest, such as hPER2, hCRY1, hBMAL1, hCCRN4L and hSMAD5 revealed significant circadian regulations. CONCLUSION: Our study revealed a proper circadian regulation profile of several clock- and tumor suppressor genes at defined points in time in the participants studied. These findings could provide important information regarding genes displaying the same expression profile in the gastrointestinal tract amounting to a physiological expression profile of healthy humans. In the future asynchronous regulations of those genes might be an additional assistant method to detect derivations distinguishing normal from malignant tissue or assessing risk factors for cancer.

Phosphoglycerate kinase 1 promoting tumor progression and metastasis in gastric cancer - detected in a tumor mouse model using positron emission tomography/magnetic resonance imaging.

BACKGROUND/AIMS: Tumor dissemination is frequent in gastric cancer and implies a poor prognosis. Cure is only achievable provided an accurate staging is performed at primary diagnosis. In previous studies we were able to show a relevant impact of increased phosphoglycerate kinase 1 expression (PGK1; a glycolytic enzyme) on invasive properties of gastric cancer in-vivo and in-vitro. Thus the aim of the present study was to evaluate the effect of enhanced PGK1 expression in gastric cancer employing magnetic resonance (MR)-imaging combined with positron emission tomography (PET), a recently emerging new high resolution imaging technique in a mouse model. METHODS: A metastatic nude mouse model simulating human gastric cancer behavior by orthotopic tumor implantation was established. Mice were divided into one control group (n=5) and two experimental groups (n=30) divided by half in animals baring tumors from MKN45-cells and MKN45-cells with plasmid-mediated overexpression of PGK1. In the course of tumor growth MR-imaging and PET/MRI fusion was performed. Successively experimental animals were examined macroscopically and histopathologically regarding growth, metastasis and PGK1 expression. RESULTS: Elevated PGK1 expression increased invasive and metastatic behavior of implanted gastric tumors significantly. MR/PET- imaging results in-vivoand subsequent ex-vivo findings concerning tumor growth and metastasis correlated excellently and could be underlined by concordant immuohistochemical PGK1 staining. CONCLUSION: Consistent in-vivo findings suggest that PGK1 might be crucially involved in gastric malignancy regarding growth and metastasis, which was also underlined by novel imaging techniques. Thus, PGK1 may be exploited as a prognostic marker and/or be of potential therapeutic value preventing malignant dissemination.

Influence of exhaustive exercise on the immune system in solid organ transplant recipients.

Prolonged exhaustive exercise has a great impact on the immune system of athletes and leads to a transient weakening of the immune system. A host of studies has documented changes of immune parameters in peripheral blood following exercise. Concerning the effect of exhaustive exercise in transplant recipients there is little knowledge at present. We analysed peripheral blood in healthy athletes and transplant recipients who participated in the "Euregio cycling tour 2009" before and immediately after they performed 81 km of cycling that included ascending more than 1800 m in altitude. A full blood count and an automated differential count as well as microarray analysis were performed before, immediately after and one day after exercise in 10 male patients carrying a kidney transplant and in 10 controls matched in age and gender. Comparing the absolute increase in neutrophils in these two groups, we detected that the relative increase in neutrophils was significantly smaller in transplant recipients compared to their corresponding controls after exhaustive exercise. While both groups were comparable in performance, microarray analysis revealed a markedly different pattern of gene expression in transplant recipients compared to their controls. From the 130 genes that were significantly upregulated in controls immediately after exercise, only 12 genes were also upregulated in transplant recipients. 64 different genes were upregulated in transplant recipients only. Our findings may be related to the immunosuppressive medication that the transplant recipients took and therefore it should also be discussed that regular exercise might reduce the need for immunosuppressive medication in transplant recipients.