Prognostic Assessment of Non-functioning Neuroendocrine Pancreatic Neoplasms as a Basis for Risk-Adapted Resection Strategies

BACKGROUND

In contrast to exocrine pancreatic carcinomas, prognosis and treatment of pancreatic neuroendocrine neoplasms (PNEN) are significantly different. The variable growth pattern and associated clinical situation of functioning and non-functioning PNEN demand an individualized surgical approach. However, due to the scarce evidence associated with the rare disease, guidelines lack detailed recommendations for indication and for the required extent of surgical resection.

METHODS

In a retrospective single-center study from 1990 to 2018, 239 patients with PNEN were identified. Clinical data were collected in the MaDoc database of the University Medical Center Mainz. A total of 155 non-functional PNEN were selected for further analysis.

RESULTS

According to the classification of NET by the WHO in 2017, 28.8% (n = 40) of the tumors were G1, 61.9% (n = 86) G2, and 9.4% (n = 13) G3. In 73 patients, hepatic metastases were present. Sixty patients had lymph node metastasis. An R0 resection was achieved in 98 cases, an R1 situation in 10 cases. Five times, a tumor debulking was carried out (R2) and 5 times the operation was aborted without any resection because of the advanced tumor stage. A relapse occurred in 29 patients. Different prognostic factors (grade, tumor size, age) were analyzed. Grade-dependent 10-year overall survival rates were 79.5% (grade 1) and 60.1% (grade 2), respectively. The survival rate of grade 3 patients was limited to 66.7% after 13 months.

CONCLUSION

In our study, patients with non-functioning PNEN had a longer overall survival after successful R0 resection. The risk analysis confirmed a Ki-67 cutoff value of 5%, which divided a high- and low-risk group. Patients with a PNEC G3 (Ki-67 index > 50%) had a very poor prognosis.

Correction to: Prognostic Assessment of Non-functioning Neuroendocrine Pancreatic Neoplasms as a Basis for Risk-Adapted Resection Strategies

This article contains parts of the doctoral thesis of F. Meyer.

Cisplatin and 5-fluorouracil with or without epidermal growth factor receptor inhibition panitumumab for patients with non-resectable, advanced or metastatic oesophageal squamous cell cancer: a prospective, open-label, randomised phase III AIO/EORTC trial (POWER)

BACKGROUND

Palliative chemotherapy of advanced oesophageal squamous cell cancer (ESCC) consists of cisplatin/5-fluorouracil (CF) to target epidermal growth factor receptor (EGFR) with panitumumab (P); chemotherapy enhanced overall survival (OS) in advanced colorectal or squamous cell head and neck cancers. With prospective serum and tumour biomarkers, we tested if P added to CF (CFP) improved OS in advanced ESCC.

PATIENTS AND METHODS

Eligible patients with confirmed ESCC that was not curatively resectable or did not qualify for definitive radiochemotherapy, were randomised 1 : 1 to receive CF [cisplatin (C) 100 mg/m² i.v., day 1; 5-fluorouracil (F) 1000 mg/m² i.v., days 1-4] or CF plus P (9 mg/kg, i.v., day 1, each q3-week cycle) until progressive disease or unacceptable toxicity. Safety was reviewed by the Data Safety Monitoring Board after 40, 70 and 100 patients who completed at least one cycle. After 53 enrolled patients, cisplatin was reduced from 100 mg/m² to 80 mg/m².

RESULTS

The trial was stopped early based on interim efficacy results triggered by the third safety analysis: median OS (mOS) favoured CF over CFP, regardless of cisplatin dose [hazard ratio (HR) 1.77, 95% confidence interval (CI) 1.06-2.98; P = 0.028]. In the final analysis, mOS was 10.2 versus 9.4 months for CF versus CFP, respectively (HR 1.17, 95% CI 0.79-1.75; P = 0.43). One hundred (70.4%) of 142 patients in the safety population died, 51 (51.0%) with CFP. Most deaths were related to disease progression [44/49 (90%) deaths in CF versus 34/51 (67%) deaths in CFP]; objective responses [27/73 (37.0%)] were identical. The most common serious adverse events were kidney injury [3 (4.3%) versus 7 (9.7%)], general health deterioration [5 (7.1%) versus 5 (6.9%)] and dysphagia [4 (5.7%) versus 4 (5.6%)] in CF versus CFP, respectively. There were three (4.3%) and 17 (23.6%) common terminology criteria for adverse events (CTCAE) grade 5 events in CF versus CFP, respectively. Low soluble (s)EGFR levels were associated with better progression-free survival; sEGFR was induced under CFP.

CONCLUSION

EGFR inhibition added to CF did not improve survival in unselected advanced ESCC patients. The results support further liquid biopsy studies.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT01627379) and EudraCT (2010-020606-15).

[Unusual dysphagia in IgG4-related disease]

This article presents the case of an IgG4-related disease in a patient with clinical signs of a malignant tumor of the oral cavity. After excluding the suspicion of a malignant lesion, vasculitis and various infectious diseases were ruled out. Finally, due to further immunohistochemical studies, IgG4-related disease was diagnosed.

[Liver injury induced by immune checkpoint inhibitor-therapy : Example of an immune-mediated drug side effect]

BACKGROUND

Drug-induced liver injury is increasing, especially in elderly patients with polymedication and multimorbidity.

OBJECTIVES

Clinicopathologic correlation of immune-mediated liver injury, specifically liver injury following therapy with immune checkpoint inhibitors against PD-1, PDL-1, and CTLA4.

METHODS

Histologic assessment of liver biopsies of nine patients after therapy with immune checkpoint inhibitors and correlation with clinical parameters.

RESULTS

In all nine patients, liver injury was apparent after variable administration of immune checkpoint inhibitors. Transaminase levels were increased up to a maximum of 3818 U/l. Liver histology showed liver injury resembling autoimmune hepatitis respective cholangitis. In two patients, veno-occlusive disease was seen. Corticosteroid therapy was initiated in eight patients, subsequently four patients showed decreasing transaminases and five patients died of tumor progress. In three patients, it remains unclear whether liver injury by immune checkpoint inhibitors may have ultimately contributed to the fatal course, especially in one patient with liver cirrhosis and hepatocellular carcinoma.

CONCLUSIONS

Therapy with immune checkpoint inhibitors may lead to potentially fatal immune phenomena in susceptible patients, which may affect liver and/or other organs independently. Other causes of hepatopathy need to be ruled out clinically and/or histologically.

Abstract P5-10-01: Cellular senescence within HER2-amplified breast cancer: Potential implications for breast cancer immune surveillance and HER2-targeted therapy resistance

Background:Oncogene-induced senescence is considered as a barrier to tumor progression that arrests cells at risk for malignant transformation. Nevertheless, numerous findings demonstrate that senescent cells may also have the opposite function and promote tumor progression through the release of multiple factors called the senescence-associated secretory phenotype or senescence secretome. It is likely that the composition and the physiological consequences mediated by the senescence secretome are dependent on the oncogenes that trigger the senescence program. Breast cancer represents a heterogenous disease that can be divided into breast cancer subtypes caused by different subsets of genetic and epigenetic abnormalities. Therefore, tumor initiation and progression of breast cancer subtypes is triggered by variable oncogenic stimuli, and differences in the senescence secretomes within breast tumors might be responsible for tumor initiation, progression, metastasis and therapeutic response. Beside many studies concerning the role of senescence as a barrier to tumor progression using murine xenograft models very few investigations have been performed to elucidate how often senescent tumor cells appear within untreated human tumors, and if present whether these senescent tumor cells may play a role in disease progression, cancer immunosurveillance and therapy resistance.

Methode: In the present study we analysed the appearance of senescent cells within invasive human breast cancers from 129 untreated patients. Cellular senescence was detected by the use of SAβ-gal staining and by immunohistochemical detection of p16, p21, p53, Ki67 and lamin B1.

Results: Detection of cellular senescence by the use of SAβ-gal staining and detection of p16, p53, Ki67 and lamin B1 within invasive breast carcinomas indicate that senescent tumor cells varies strongly according to the breast cancer subtype. The highest percentages of senescent tumor cells exist within in the HER2-positive and luminal A breast carcinomas whereas no or very few senescent tumor cells were found in triple negative breast tumors. Based on these findings we suggest that the composition of secretomes released by senescent tumor cells from different breast cancer subtypes might be very distinct in respect to their ability to recruit immune cells, which can eliminate senescent tumor cells on one hand and regulate tumor growth, immune surveillance and therapy resistance on the other.

Conclusion: Further characterization of senescent secretomes from HER2 and other breast cancer subtypes and their potential role in tumor progression, immune surveillance and therapy response might be warranted for the understanding of cancer biology as well as prognostic and therapeutic applications.

Citation Format: Thaler S, Schad A, Kirkpatrick CJ, Sleeman JP, Springer E, Schmidt M, Cotarelo CL. Cellular senescence within HER2-amplified breast cancer: Potential implications for breast cancer immune surveillance and HER2-targeted therapy resistance [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-10-01.

Abstract P6-12-14: Proteasome inhibitors prevent bi-directional HER2/estrogen-receptor cross-talk leading to cell death in endocrine and lapatinib-resistant HER2+/ER+ breast cancer cells

Background:Aberrant signaling through HER2 and other members of the HER family has been identified as mediator of endocrine resistance in estrogen receptor alpha (ERα) positive breast cancer. On the other hand, ERα co-expression has been shown to attenuate the efficiency of anti-HER2 targeted therapies. These findings indicate that HER2 and ERα synergize to allow breast cancer cells to escape from both anti-ERα and anti-HER2-targeted therapies. Rationally designed clinical trials that combine endocrine therapy with anti-HER2 agents to interfere with HER2/ERα cross-talk have been conducted. However, the outcome of these trials suggests that novel therapeutic approaches are needed to further improve inhibition of HER2 and other HER family members in conjunction with a more efficient ERα blockade. We examined the ability of proteasome inhibitors (PIs) to disrupt HER2/ERα cross-talk in HER2+/ER+ breast cancer (BC) cells. Furthermore we investigated the potential of PIs to suppress the activity of a constitutively active HER2 variant resistant to trastuzumab and lapatinib.

Methode: HER2+/ER+ BC cells and fulvestrant resistant ER+ BC cells that overexpress a constitutively active HER2 variant resistant to trastuzumab and lapatinib have been treated with the PIs carfilzomib and bortezomib. The potential of these PIs to suppress ERα expression, to block HER2 activation and to inhibit the HER2 downstream pathways PI3K/Akt and Ras/MAPK was monitored by western blotting. Induction of cell death upon PI treatment was measured by quantification of SubG1 cells using propidium iodide staining or the use of colony formation assays.

Results: Carfilzomib and bortezomib markedly inhibit bi-directional HER2/ERα signaling pathways in HER2/ER+ BC cells. Both PIs suppress ERα expression, inhibit HER2 activity and subsequently suppress the HER2 downstream pathways PI3K/Akt and Ras/MAPK that are major executors for endocrine resistance. Furthermore we observed that both PIs stabilize the HER2 specific tyrosine phosphatase BDP1 (PTPN18), thereby suppressing the activity of even a constitutive active HER2 variant that cause resistance to trastuzumab and lapatinib. Based on these findings we hypothesize that PIs inhibits ERα and HER2 activity through different mechanisms as currently used therapeutic regiments.

Conclusion: These findings demonstrate that PIs disrupt the cross-talk between HER2 and ERα signaling pathways and therefore might have the potential to expand treatment opportunities for HER2+/ER+ and possibly also for other groups of BC patients.

Citation Format: Thaler S, Schmidt M, Thiede G, Schad A, Sleeman JP. Proteasome inhibitors prevent bi-directional HER2/estrogen-receptor cross-talk leading to cell death in endocrine and lapatinib-resistant HER2+/ER+ breast cancer cells [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-12-14.

Surgical Treatment of NEN of Small Bowel: A Retrospective Analysis

BACKGROUND

Neuroendocrine Neoplasms of the small intestine have been noticed more frequently over the past 35 years. They constitute about 25% of all NENs and 29% of all tumors of the small intestine. Due to the predominantly indolent nature and overall good prognosis, the benefit of surgical treatment is still debated.

METHODS

In a retrospective study, data of 83 surgically treated patients with neuroendocrine neoplasms of the small intestine, 48 males and 35 females with a median age of 62 years (range 25-86 years) were analyzed. Patient data were documented in the MaDoc database for neuroendocrine tumors of the University Medical Center of Mainz. IBM SPSS Statistics 20 was used for statistical analysis. Kaplan-Meier survival curves and Log-Rank tests, censoring patients at the time of last follow-up, were used to compare the overall survival depending on potential prognostic factors (stage, grade, surgical treatment).

RESULTS

At the time of diagnoses, the most common clinical symptoms were abdominal pain (n = 31, 37.3%), bowel obstruction (n = 11, 13.3%), bowel perforation and peritonitis (n = 3, 3.6%), gastrointestinal bleeding (n = 9, 10.8%), weight loss (n = 11, 13.3%), and carcinoid syndrome (n = 27, 32.5%). 65 patients (78.3%) had lymph node metastasis and in 58 patients (69.9%) distant metastasis were present. Segmental bowel resection (44) was the most common surgical procedure, followed by right hemi-colectomy (32) and explorative laparotomy (7). In most patients (78.9%), lymphadenectomy (systematic/selective) was performed. The 5-year survival of patients who underwent a systematic or a selective lymphadenectomy differed significantly (82.2 vs. 40.0%). The overall 3-, 5-, and 10-year survival rates were 88.2, 80.3, and 71.0%, respectively.

CONCLUSION

Mesenteric lymph node metastases are almost invariably present and have significant impact on patients' prognosis. Systematic lymphadenectomy prevents complications and improves the survival. Early surgical treatment should be the goal in order to prevent complications.

Pulmonary effects of expiratory-assisted small-lumen ventilation during upper airway obstruction in pigs

Novel devices for small-lumen ventilation may enable effective inspiration and expiratory ventilation assistance despite airway obstruction. In this study, we investigated a porcine model of complete upper airway obstruction. After ethical approval, we randomly assigned 13 anaesthetised pigs either to small-lumen ventilation following airway obstruction (n = 8) for 30 min, or to volume-controlled ventilation (sham setting, n = 5). Small-lumen ventilation enabled adequate gas exchange over 30 min. One animal died as a result of a tension pneumothorax in this setting. Redistribution of ventilation from dorsal to central compartments and significant impairment of the distribution of ventilation/perfusion occurred. Histopathology demonstrated considerable lung injury, predominantly through differences in the dorsal dependent lung regions. Small-lumen ventilation maintained adequate gas exchange in a porcine airway obstruction model. The use of this technique for 30 min by inexperienced clinicians was associated with considerable end-expiratory collapse leading to lung injury, and may also carry the risk of severe injury.

Surgical therapy of neuroendocrine neoplasm with hepatic metastasis: patient selection and prognosis

BACKGROUND

Patients with neuroendocrine neoplasms (NEN) develop hepatic metastases in 50-95 %. The aims of this study were to evaluate the outcome/prognosis of patients following hepatic surgery and to identify predictive factors for the selection of patient that benefit from hepatic tumor resection.

PATIENTS AND METHODS

In a retrospective single-center study (1990 to 2014), 204 patients with hepatic metastasis of NEN were included. Ninety-four were subjected to various forms of liver resection. According to the overall survival, the influence of several prognostic factors like the Ki-67 index, stage of disease, and resection status was evaluated.

RESULTS

The primary tumor was located in the small intestine (n = 73), pancreas (n = 58), colon (n = 26), esophagus or stomach (n = 9) and in 38 patients the primary site was unknown. The Ki-67 index was associated with significant different overall survival. Patients with an R0 resection (n = 38) of their hepatic metastasis had a very good 10-year survival of 90.4 %. Patients in whom an R1 (n = 23) or R2 (n = 33) resection of their hepatic metastasis could be achieved had a 10-year survival of 53.4 and 51.4 %, respectively. The majority of the patients (53.9 %) could not be resected and had a poor 10-year survival rate of 19.4 %. Partial or complete control of endocrine-related symptoms was achieved in all patients with functioning tumors following surgery. The overall 5- and 10-year survival rates were 77.9 and 65.2 %, respectively.

CONCLUSION

Surgical resection of hepatic NEN metastases can reduce symptoms and improve the survival in selected patients with a Ki-67 index less than 20 %. The expected outcome has to be compared to the outcome of alternative treatment strategies. An R0 situation should be the aim of hepatic surgery, but also patients with R1 or R2 resection show a good survival benefit.

[Pleural effusion cytology of asbestos-associated malignant mesothelioma and lung carcinoma in the diagnosis of occupational diseases by the statutory accident insurance funds]

Pleural effusion often represents the first clinical symptom of lung carcinoma and malignant mesothelioma. As pleural punctation is performed quite early in the diagnostic procedure, effusion cytology frequently gives the first evidence about the presence of tumour cells and tumor histogenesis. In this study, we report on seven cases which were evaluated in our institution for the Employers' Liability Insurance Association, based solely on cytology findings.The mean age of the seven patients with a given long-term asbestos exposure during their working life was 81.7 years. On average eight smears per patient were investigated. In addition to routine cytology, immunocytochemistry, DNA image cytometry, AgNOR-analysis and fluorescence in situ hybridization were applied in a case-specific way. The results were interpreted against the clinical and occupational history of the respective patient.Definitive diagnosis could be made in six cases. In three of them, the diagnosis of malignant mesothelioma was made. Two cases were diagnosed as malignant effusion due to metastatic lung cancer. In one case, cells of high-grade Non-Hodgkin's lymphoma (NHL) were diagnosed and a malignant mesothelioma was excluded. In the last case, malignant mesothelioma could not be diagnosed unequivocally by cytology. In all seven cases, our interpretation was accepted by Employers' Liability Insurance Association. The five mesothelioma or lung cancer cases were accepted as asbestos-associated occupational disease, while the NHL case was rejected. In the last case, malignant mesothelioma was diagnosed later by autopsy, and the case was retroactively accepted as occupational disease.Cytology-based tumor diagnosis including adjuvant methods is a useful and reliable approach in cases of asbestos-associated tumours. Acceptance of occupational disease on the basis of cytological diagnoses even by the Employers' Liability Insurance Association helps avoid invasive pleural or lung biopsies in cases with an unequivocally positive effusion cytology of lung cancer or malignant mesothelioma.

[Drug-induced liver injury with an autoimmune phenotype following anti-TNF Therapy - presentation of cases and review of literature]

Therapeutic agents to inhibit tumour necrosis factor alpha (TNF-α) have dramatically improved the treatment options for patients with autoimmune diseases. Common side effects include an increased susceptibility towards infection. Hepatic side effects are less frequently observed. Elevated liver function tests, hyperbilirubinaemia reactivation of chronic viral hepatitis or even acute liver failure have been described. Some cases have exhibited an autoimmune phenotype with the emergence of autoantibodies and characteristic histological lesions. We report on three patients who received anti-TNF therapy for psoriasis and presented with elevated liver function tests in the further course. Histological and serum analysis revealed an autoimmune phenotype of liver injury. In light of the growing use of anti-TNF therapies, drug-induced liver injury (DILI) with an autoimmune phenotype is an important side effect. Since the pathophysiological mechanisms related to the autoimmune phenotype of liver injury during TNF-inhibition are not well understood, the cases detailed herein should help treating physicians to improve their understanding of the situation.

Diabetic liver injury from streptozotocin is regulated through the caspase-8 homolog cFLIP involving activation of JNK2 and intrahepatic immunocompetent cells

The endemic occurrence of obesity and the associated risk factors that constitute the metabolic syndrome have been predicted to lead to a dramatic increase in chronic liver disease. Non-alcoholic steatohepatitis (NASH) has become the most frequent liver disease in countries with a high prevalence of obesity. In addition, hepatic steatosis and insulin resistance have been implicated in disease progression of other liver diseases, including chronic viral hepatitis and hepatocellular carcinoma. The molecular mechanisms underlying the link between insulin signaling and hepatocellular injury are only partly understood. We have explored the role of the antiapoptotic caspase-8 homolog cellular FLICE-inhibitory protein (cFLIP) on liver cell survival in a diabetic model with hypoinsulinemic diabetes in order to delineate the role of insulin signaling on hepatocellular survival. cFLIP regulates cellular injury from apoptosis signaling pathways, and loss of cFLIP was previously shown to promote injury from activated TNF and CD95/Apo-1 receptors. In mice lacking cFLIP in hepatocytes (flip^−/−), loss of insulin following streptozotocin treatment resulted in caspase- and c-Jun N-terminal kinase (JNK)-dependent liver injury after 21 days. Substitution of insulin, inhibition of JNK using the SP600125 compound in vivo or genetic deletion of the mitogen-activated protein kinase (MAPK)9 (JNK2) in all tissues abolished the injurious effect. Strikingly, the difference in injury between wild-type and cFLIP-deficient mice occurred only in vivo and was accompanied by liver-infiltrating inflammatory cells with a trend toward increased amounts of NK1.1-positive cells and secretion of proinflammatory cytokines. Transfer of bone marrow from rag-1-deficient mice that are depleted from B and T lymphocytes prevented liver injury in flip^−/− mice. These findings support a direct role of insulin on cellular survival by alternating the activation of injurious MAPK, caspases and the recruitment of inflammatory cells to the liver. Thus, increasing resistance to insulin signaling pathways in hepatocytes appears to be an important factor in the initiation and progression of chronic liver disease.

Inhibition of Rac1 signaling by lovastatin protects against anthracycline-induced cardiac toxicity

Normal tissue damage limits the efficacy of anticancer therapy. For anthracyclines, the clinically most relevant adverse effect is cardiotoxicity. The mechanisms involved are poorly understood and putative cardioprotectants are controversially discussed. Here, we show that the lipid-lowering drug lovastatin protects rat H9c2 cardiomyoblasts from doxorubicin in vitro. Protection by lovastatin is related to inhibition of the Ras-homologous GTPase Rac1. It rests on a reduced formation of DNA double-strand breaks, resulting from the inhibition of topoisomerase II by doxorubicin. Doxorubicin transport and reactive oxygen species are not involved. Protection by lovastatin was confirmed in vivo. In mice, lovastatin mitigated acute doxorubicin-induced heart and liver damage as indicated by reduced mRNA levels of the pro-fibrotic cytokine connective tissue growth factor (CTGF) and pro-inflammatory cytokines, respectively. Lovastatin also protected from doxorubicin-provoked subacute cardiac damage as shown by lowered mRNA levels of CTGF and atrial natriuretic peptide. Increase in the serum concentration of troponin I and cardiac fibrosis following doxorubicin treatment were also reduced by lovastatin. Whereas protecting the heart from harmful doxorubicin effects, lovastatin augmented its anticancer efficacy in a mouse xenograft model with human sarcoma cells. These data show that statins lower the incidence of cardiac tissue injury after anthracycline treatment in a Rac1-dependent manner, without impairing the therapeutic efficacy.

[Achalasia in a patient with HIV/HCV coinfection: detection of HCV in the esophageal tissue]

Esophageal involvement in the context of opportunistic infections in human immunodeficiency virus (HIV) positive patients is a frequent phenomenon. However, worldwide esophageal achalasia has been described only twice in HIV-infected patients.We report the case of a 44-year-old Caucasian patient with HIV and Hepatitis C virus (HIV/HCV) coinfection who, within 2.5 years, displayed a progressive symptomatology with dysphagia, retrosternal pain, regurgitation as well as a considerable loss of weight before achalasia was finally diagnosed. Treatment was performed primarily surgically by means of laparoscopic Heller myotomy with an anterior 180° semifundoplication according to Dor.Histopathology of the specimens taken from the lower esophageal sphincter high-pressure zone proved alterations with abundant connective tissue and only scarce parts of the smooth muscular system without inflammatory infiltrations. In addition, the ganglia cells of the myenteric plexus as well as the interstitial cells of Cajal were significantly reduced. Interestingly, specific gene sequences of the hepatitis C virus could be detected in the esophageal tissue specimen. In contrast, analysis of specific HIV-gene sequences in the same tissue revealed a negative result.The possible but previously unknown relationship between esophageal achalasia and coinfection with HIV and HCV, also described as neurotropic viruses, will be discussed.

Organ recipients suffering from undifferentiated neuroendocrine small-cell carcinoma of donor origin: a case report

BACKGROUND

Transmission of donor-derived cancer by organ transplantation is rare, but the risk has been increasing due to the aging donor pool. Undifferentiated neuroendocrine small-cell carcinoma is an aggressive tumor with the tendency to spread. Herein we have demonstrated different approaches to treat organ recipients with transmitted tumors.

METHODS AND RESULTS

Grafts were retrieved from a decreased donor without any history of previous diseases. Autopsy was not performed after donation. The recipient of the liver graft presented with suspected nodules on routine abdominal ultrasound. After computed tomography (CT) scan, biopsy confirmed the diagnosis of a small-cell carcinoma. Donor origin was unequivocally identified by DNA fingerprinting. Despite chemotherapy the patient died 7 months after orthotopic liver transplantation (OLT). All involved transplantation centers were informed immediately following diagnosis. The male kidney recipient underwent detailed diagnostic work-up to exclude tumor transmission. One year after transplantation, liver metastases caused by a histologically proven small-cell carcinoma from the same donor were apparent. Chemotherapy was immediately started and the graft was removed. Despite continued treatment the tumor progressed and the patient died after repeated intestinal complications. The pathological examination of the explanted second kidney graft did not show any tumor infiltration.

CONCLUSION

Therapeutic regimens in recipients suffering from donor-derived carcinoma differ depending on the transplanted organ. Graft removal of non-life-sustaining organs and discontinuation of immunosuppressive medication should result in complete tumor rejection. Minimizing the risk of tumor transmission, a CT scan might be advisable in donors of more advanced age.

Hepatocellular Injury of Nonischemic Liver Tissue after Selective Clamping in Rats – Protective Action by Pharmacological Pretreatment with Lipoic Acid

BACKGROUND/AIM

The aim of the study was to characterize the hepatic injury (HI) of the nonischemic liver lobe after selective portal triad clamping and investigate the influence of pharmacological pretreatment with alpha-lipoic acid (LA).

METHODS

Brown-Norway rats received 500 micromol LA injected via the inferior vena cava 15 min prior to the induction of 90 min of selective ischemia. Another group of rats received vehicle prior to ischemia. Both groups were compared with sham-operated animals.

RESULTS

Lipid peroxidation (LPO) was increased in the ischemic as well as in the nonischemic liver tissue (NIL) in the untreated group. Levels of adenosine triphosphate and reduced glutathione content of the nonischemic liver lobe were decreased in the untreated group 1 h after reperfusion. Activity of caspases 3 and 8 was not detectable, whereas expression of the Bax protein was demonstrated in the NIL. We observed areas of necrotic hepatocytes and large gaps of sinusoids in the NIL of the untreated rats. LA attenuated LPO as well as Bax expression in the NIL. Moreover adenosine triphosphate and glutathione content of the NIL was increased 1 h after reperfusion by LA. LA pretreatment reduced release of alpha-glutathione-s-transferase in plasma. Histology of the nonischemic liver lobe did not markedly differ from sham-operated animals after LA pretreatment.

CONCLUSION

HI of the NIL seems to be mediated by LPO and proapoptotic proteins such as Bax. Besides its described potential to reduce ischemia/reperfusion injury of the ischemic lobe, LA attenuates HI of the nonischemic tissue after selective portal triad clamping.

Tissue- and cell-specific expression of metallothionein genes in cadmium- and copper-exposed mussels analyzed by in situ hybridization and RT–PCR

Metallothioneins (MTs) are metal-inducible proteins that can be used as biomarkers of metal exposure. In mussels two families of MT isoforms (MT10 and MT20) have been characterized. In this study, mussels (Mytilus galloprovincialis) were exposed to 200 ppb Cd and 40 ppb Cu for 2 and 9 days to characterize the tissue and isoform specificity of metal-induced MT expression. Non-radioactive in situ hybridization demonstrated that both MT isoforms were mainly transcribed in digestive tubule epithelial cells, especially in basophilic cells. Weaker MT expression was detected in non-ciliated duct cells, stomach and gill epithelial cells, haemocytes, adipogranular cells, spermatic follicles and oocytes. RT-PCR resulted in cloning of a novel M. galloprovincialis isoform homologous to recently cloned Mytilus edulis intron-less MT10B isoform. In gills, Cd only affected MT10 gene expression after 2 days of exposure while increases in MT protein levels occurred at day 9. In the digestive gland, a marked increase of both isoforms, but especially of MT20, was accompanied by increased levels of MT proteins and basophilic cell volume density (Vv(BAS)) after 2 and 9 days and of intralysosomal metal accumulation in digestive cells after 9 days. Conversely, although metal was accumulated in digestive cells lysosomes and the Vv(BAS) increased in Cu-exposed mussels, Cu exposure did not produce an increase of MT gene expression or MT protein levels. These data suggest that MTs are expressed in a tissue-, cell- and isoform-specific way in response to different metals.

Expression of peroxisomal proteins provides clear evidence for the presence of peroxisomes in the male germ cell line GC1spg

Peroxisomes are cell organelles that perform multiple functions in the metabolism of lipids and of reactive oxygen species. They are present in most eukaryotic cells. However, they are believed to be absent in spermatozoa and they have never been described in male germ cells. We have used the immortalized germ cell line GC1spg to investigate the expression of peroxisomal proteins in germ cells of mice. The GC1spg cells represent the differentiation state of type B spermatogonia or preleptotene spermatocytes. We could show that peroxisomal membrane proteins like Pmp70 and Pex14p as well as peroxisomal matrix proteins like catalase or acyl CoA oxidase are expressed in GC1spg cells. All these proteins were colocalized in the same structures within the cells. Furthermore, by electron microscopy we have identified subcellular particles with an ultrastructural appearance that is characteristic of peroxisomes. This is the first report demonstrating the peroxisomal compartment in male germ cells of mice.

[Intraligamentous suture of a scapholunar ligament lesion in a 9-year-old child]

Scapholunate dissociation is a well-known injury in adult patients. In pediatric patients, repair of this injury in the skeletally immature carpus has been previously reported. However, in none of these case studies is single ligamentous suture performed. We report a case of scapholunate dissociation in a 9-year-old boy after an initial Salter I injury of the distal radius. After 6 weeks of wrist immobilization, arthroscopy was performed due to persisting pain over the scapholunate gap, a positive Watson sign, and limited range of motion. This arthroscopy revealed intraligamentous rupture of the scapholunate ligament. Suture repair of the scapholunate ligament was performed. The suture was protected by a temporary K-wire arthrodesis for 8 weeks. One year after removal of the K-wire, the patient is completely free of symptoms and resumes all sport activities.

Localization of mRNAs encoding peroxisomal proteins in cell culture by non-radioactive in situ hybridization. Comparison of rat and human hepatoma cells and their responses to two divergent hypolipidemic drugs

A non-radioactive in situ hybridization (ISH) protocol for localization of mRNAs encoding peroxisomal proteins in hepatoma cell lines from humans (HepG2) and rats (MH1C1) is presented. In comparison to a similar procedure reported for tissue sections, the cell culture preparations require only brief fixation in 4% paraformaldehyde and their permeabilization is achieved by a very low concentration (1 microg/ml) of proteinase K. The exclusive localization of transcripts in the cytoplasm of hepatoma cells with the absence of nuclear staining and the completely negative sense controls confirm the specificity of the method. The marked differences in signal intensity between the results of albumin and beta-actin mRNAs which are of high abundance in contrast to moderate to low abundance of peroxisomal mRNAs show the high sensitivity and the wide range of applicability of our protocol. This is also confirmed by divergent results of treatment of hepatoma cell lines with clofibrate and cetaben on mRNA levels of catalase and acyl-CoA oxidase. The ISH results of drug treatment of cell lines are confirmed also by slot blot analysis of total RNA extracts using 32P-labeled probes. Thus the protocol presented here provides a sensitive tool for ISH localization of mRNAs encoding peroxisomal proteins. In combination with immunocytochemistry it may be useful to monitor intercellular differences in expression levels of specific mRNAs in correlation with the abundance of structurally divergent forms of peroxisomes (tubular versus spherical) and their importance in the biogenesis of peroxisomes.

Detection of mRNAs encoding peroxisomal proteins by non-radioactive in situ hybridization with digoxigenin-labelled cRNAs

We have used a non-radioactive in situ hybridization (ISH) protocol for the detection of mRNAs encoding proteins localized in peroxisomes. In this presentation the literature on detection of "peroxisomal mRNAs" is reviewed and the results obtained by application of the non-radioactive method are compared with those obtained by hybridization with radioactive probes. Moreover, the special processing conditions and the application of the method for the specific visualization of mRNAs coding for several peroxisomal proteins with different abundance levels and distinct tissue distributions are presented. The combination of the following technical details in the ISH procedure were found to be essential for obtaining optimal sensitivity and good histological quality of the preparations: (a) perfusion-fixation with a fixative containing 4% depolymerized paraformaldehyde/0.05% glutaraldehyde, (b) the use of paraffin embedding instead of frozen sections, (c) specific proteinase K-digestion time for each tissue, and (d) the use of digoxigenin-labelled cRNA probes (hydrolyzed to a length of about 200 bases) for detection. By using this technique, we were able to localize several peroxisome-specific mRNAs with different degrees of abundance: (1) high-level (catalase and urate oxidase) and (2) low-level (all beta-oxidation enzymes and the 70-kDa peroxisomal membrane protein) in rat liver and kidney. The specificity of the method was confirmed by the negative results obtained with corresponding sense controls and the distinct positive staining patterns obtained for albumin and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNAs. All transcripts for mRNAs encoding peroxisomal proteins were localized to the cytoplasm of hepatocytes, with all nuclei as well as epithelial cells of bile ducts and sinusoidal cells remaining negative. In rat kidney, the catalase transcripts were confined to proximal tubular epithelial cells, which is consistent with the high abundance of peroxisomes in this part of the nephron. In contrast, no transcripts for urate oxidase were present in the kidney, corresponding to the absence of that protein in this organ. The transcripts for GAPDH on the other hand were localized in proximal and distal tubular epithelial cells as well as in collecting ducts. The application of this technique to the rat adrenal gland and testis in recent unpublished studies have revealed exclusive localization of catalase transcripts to the adrenal cortex and to interstitial cells of Leydig, which are known to be rich in microperoxisomes. These observations demonstrate the suitability of this technique for accurate localization of mRNAs encoding peroxisomal proteins and for the analysis of alterations in the expression of the corresponding genes under different experimental conditions.

Nonradioactive in situ hybridization for detection of mRNAs encoding for peroxisomal proteins: heterogeneous hepatic lobular distribution after treatment with a single dose of bezafibrate

We present a nonradioactive in siru hybridization (ISH) protocol for detection of mRNAs in rat liver encoding for three peroxisomal proteins: catalase and urate oxidase as representatives of high-level abundance mRNAs and trifunctional protein (PH) as that of low-level abundance mRNAs. In addition to normal rats, animals treated for 24 hr with a single dose of bezafibrate were studied. The use of perfusion-fixation with 4% depolymerized paraformaldehyde/0.05% glutaraldehyde combined with paraffin embedding and the application of digoxigenin-labeled cRNA probes provided optimal cytological resolution and high sensitivity comparable to that of radioactive ISH. In parallel experiments, the same digoxigenin-labeled cRNA probes were used for Northern and semiquantitative dot-blot analysis of isolated RNAs. In control animals, the mRNAs for catalase and urate oxidase were uniformly distributed across the liver lobule and were confined to liver parenchymal cells. The bile duct epithelial and the sinusoidal cells remained negative. The specificity and the high resolution of our protocol were further substantiated by reciprocal localization of transcripts for albumin and glyceraldehyde-3-phosphate dehydrogenase in different regions of the liver lobule and for catalase in the proximal tubules of the renal cortex. Whereas in control livers the transcripts for PH were barely detectable, a strong signal was found in pericentral hepatocytes of bezafibratetreated animals, corresponding to an 8-10-fold increase of mRNA detected in dot-blots. In contrast, the urate oxidase mRNA was reduced by more than 50%, with diminution of staining in pericentral regions of the liver lobule. The mRNA encoding for catalase was only slightly affected. Further applications of this protocol should be helpful in elucidation of the cell-specific transcriptional regulation of peroxisomal proteins in various organs under normal and pathological conditions.