[Gliomas in the elderly]

The incidence of malignant gliomas is growing in the elderly population. Unfortunately, increasing age is one of the most important negative prognostic factors in gliomas and the optimal management of this population remains largely unsettled because older patients are often excluded from clinical trials. However, the classic nihilistic approach is progressively changing towards more active strategies. Particularly, prospective randomized studies have recently established the benefit of radiation therapy and the validity of an accelerated course of radiation in older patients suffering from malignant gliomas. The interest of chemotherapy, alone or concomitant with radiation therapy is still under evaluation in this population. Initial performance status, quality of life and concomitant pathologies are important factors to consider before treatment onset. In the future, it will be necessary to develop specific schedules of treatment in this population.

High levels of HIF-2alpha highlight an immature neural crest-like neuroblastoma cell cohort located in a perivascular niche

High HIF-2alpha protein levels in the sympathetic nervous system-derived childhood tumour neuroblastoma as well as immature phenotype correlate to unfavourable outcome. Here we show that a small subset of perivascularly located, strongly HIF-2alpha-positive tumour cells (MYCN amplified) lacks expression of differentiation markers, but expresses neural crest and early sympathetic progenitor marker genes such as Notch-1, HES-1, c-Kit, dHAND, and vimentin. HIF-2alpha- and CD68-positive tumour-associated macrophages were frequently found close to the immature and HIF-2alpha-positive neuroblastoma cells and as VEGF levels are high in the perivascular niche, we hypothesize that neuroblastoma neural crest-like cells and macrophages cooperate to facilitate angiogenesis and thereby contribute to the aggressive neuroblastoma phenotype.

The cytotoxicity of eosinophil cationic protein/ribonuclease 3 on eukaryotic cell lines takes place through its aggregation on the cell membrane

Human eosinophil cationic protein (ECP)/ ribonuclease 3 (RNase 3) is a protein secreted from the secondary granules of activated eosinophils. Specific properties of ECP contribute to its cytotoxic activities associated with defense mechanisms. In this work the ECP cytotoxic activity on eukaryotic cell lines is analyzed. The ECP effects begin with its binding and aggregation to the cell surface, altering the cell membrane permeability and modifying the cell ionic equilibrium. No internalization of the protein is observed. These signals induce cell-specific morphological and biochemical changes such as chromatin condensation, reversion of membrane asymmetry, reactive oxygen species production and activation of caspase-3-like activity and, eventually, cell death. However, the ribonuclease activity component of ECP is not involved in this process as no RNA degradation is observed. In summary, the cytotoxic effect of ECP is attained through a mechanism different from that of other cytotoxic RNases and may be related with the ECP accumulation associated with the inflammatory processes, in which eosinophils are present.

Colorectal stenting as an effective therapy for preoperative and palliative treatment of large bowel obstruction: 9 years' experience

BACKGROUND

Since their introduction, selfextending metal stents (SEMS) have established themselves as an option in the treatment of obstructive colorectal cancer. Thanks to stenting, patients traditionally treated with emergency surgery can now be converted to scheduled surgery with mechanical preparation of the colon and primary anastomosis. Stenting represents a valid one-step surgical alternative for intestinal obstruction of the colon.

METHODS

We performed a prospective study of 95 patients (mean age, 68 years; range 48-94) with large bowel obstruction due to colorectal cancer treated with SEMS placed under fluoroscopic guidance, some as a bridge to surgery (group A) and others with palliative intent (group B). Computed tomography was performed for diagnostic purposes and to study the extent of disease.

RESULTS

Treatment was palliative in 28 cases (group B) and as a bridge to surgery in 67 (group A). The latter group underwent mechanical preparation of the colon and elective surgery. No patients died as a result of the procedure. In 90 cases (95%), treatment was effective and the obstruction resolved. Complications were 4 cases of perforation, 1 of tenesmus, 4 obstructions and 4 migrations. In 7 cases, a second stent was inserted to allow subsequent scheduled surgery.

CONCLUSIONS

Self-extending stents resolve colorectal cancer obstruction and allow optimal patient staging and scheduled surgical treatment. Stenting is also a useful option in advanced or irresectable tumors, avoiding the need for surgery and offering good palliation.

Apoptosis in peripheral neuroblastic tumors. Immunohistochemical expression of bcl-2 and p53 is related to DNA fragmentation

We examined 111 cases of neuroblastoma (NB), searching for how NB relates to apoptotic control and other prognostic factors. Immunohistochemistry using avidin-biotin-peroxidase was carried out for bcl-2 and p53 proteins. Apoptosis was analyzed by in situ detection of chromosomal breakdown. DNA ladders were detected by electrophoresis and amplification of MYCN was carried out by PCR and Southern blot. Statistical analyses were performed with Pearson's chi2 and Kruskal-Wallis tests and Cox's regression. We found expression of bcl-2 protein mainly in cases of neuroblastoma without differentiation and in stages 3 and 4. Expression of p53 protein showed a correlation with bcl-2 and the apoptotic phenomenon; apoptosis was found mainly in favorable cases. Multivariate analysis showed bcl-2 protein expression to be the most independent risk factor. The study of apoptosis could be important for the design of therapies to treat neuroblastoma.

Polymorphisms in the endothelial protein C receptor gene and thrombophilia

The protein C anticoagulant pathway plays a crucial role as a regulator of the blood clotting cascade. Protein C is activated on the vascular endothelial cell membrane by the thrombin-thrombomodulin complex. Once formed, activated protein C (APC) down-regulates thrombin formation by inactivating factors (F)Va and FVIIIa. Endothelial protein C receptor (EPCR) is able to bind protein C and increase the rate of protein C activation. Normal APC generation depends on the precise assemblage, on the surface of endothelial cells, of thrombin, thrombomodulin, protein C and EPCR. Therefore, any change in the efficiency of this assemblage may cause reduced/increased APC generation and modify the risk of thrombosis. This review highlights the different mutations/polymorphisms reported in the EPCR gene and their association with the risk of thrombosis.

In vitro and in vivo expression of human erythrocyte pyruvate kinase in erythroid cells: a gene therapy approach

Human pyruvate kinase deficiency (PKD), an autosomal recessive disorder produced by mutations in the PKLR gene, is the most common cause of chronic nonspherocytic hemolytic anemia. Transduction of wild-type erythroid (R-type) pyruvate kinase (RPK) cDNA into deficient hematopoietic stem cells could be of potential use as rescue therapy in severe clinical cases. In this study, gammaretroviral vectors expressing human RPK were designed as possible gene therapy candidates for this disease. Through real-time quantitative reverse transcriptase-polymerase chain reaction, Western blotting, and flow cytometric analysis, we demonstrate stable RPK expression in both undifferentiated and differentiated murine erythroleukemia cells. In this in vitro assay, the proportion of transduced cells and the intensity of expression of the transgene remained unaltered after 6 months of culture. Moreover, transplanting human RPK-transduced Lin(-)Sca-1(+) mouse cells in myeloablated primary and secondary recipients rendered high proportions of erythroid precursors and mature erythrocytes expressing RPK, without inducing hematopoietic effects. These findings suggest that retroviral vectors could be useful for the delivery and expression of RPK in erythroid cells, and provide evidence of the potential use of gene therapy strategies to phenotypically correct erythroid PKD.

Decline of pesticide residues from barley to malt

The fate of dinitroaniline herbicides (pendimethalin and trifluralin), organophosphous insecticides (fenitrothion and malathion), and pyrimidine (nuarimol) and triazole (myclobutanil and propiconazole) fungicides from barley to malt was determined. Several samples for residue analysis were taken after each stage of malting (steeping, germination and kilning). Pesticide residue analysis was carried out by GC/ITMS in selected ion monitoring mode. Pesticides decline along the process, although in different proportions. The carryover of residues after steeping was 45-85%. A good correlation (r > 0.92) was observed between percentages removed after steeping and the P(OW) values of pesticides. The amount remaining after malting ranged from 13 to 51% for fenitrothion and nuarimol, respectively. Steeping was the most important stage in the removal of pesticide residues (52%) followed by germination (25%), and kilning (drying and curing, 23%). During malt storage (3 months) the fall in pesticide residues was not significant. Applying the standard first-order kinetics equation (r > 0.95), the half-lives obtained for the pesticides during malt storage varied from 244 to 1533 days for myclobutanil and nuarimol, respectively.

Incidence and clinical significance of hyperamylasemia after endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of pancreatic lesions: a prospective and controlled study

BACKGROUND AND STUDY AIM

Acute pancreatitis as a complication of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of pancreatic lesions is rarely observed. However, there is little information on the incidence of hyperamylasemia after EUS-FNA of the pancreas and its clinical significance. This study aimed to supply this lack of information.

PATIENTS AND METHODS

Patients who underwent EUS-FNA of a pancreatic lesion between October 2004 and October 2005 were studied prospectively. Exclusion criteria were: (i) platelet count under 50,000/mm (3) and/or prothrombin time < 50 %; (ii) performance of surgery, endoscopic retrograde cholangiopancreatography (ERCP), a percutaneous biopsy attempt, or another invasive procedure within 7 days before EUS-FNA; (iii) lack of informed consent. Serum amylase levels were determined before and 8 and 24 h after the procedure. Hyperamylasemia was defined by amylase levels above 104 UI/L (and higher than baseline levels) 8 h after the procedure. Acute pancreatitis was defined by upper abdominal pain (with or without nausea and/or vomiting) accompanied by elevation of serum amylase or lipase to at least twice baseline levels.

RESULTS

A total of 100 patients underwent EUS-FNA of a pancreatic lesion (58 men, 42 women; mean age 60 +/- 13 years). Eleven patients (11 %) showed hyperamylasemia 8 h after the puncture (298 +/- 293 UI/L, range 105 - 1044 UI/L), but only two of them developed acute mild pancreatitis after EUS-FNA. Hyperamylasemia was not related either to the type of lesion (cystic or solid) or to its location, the duration of the procedure, or the number of passes performed.

CONCLUSIONS

Pancreatitis after pancreatic EUS-FNA occurs in 2 % of patients, with some more cases of silent hyperamylasemia. This complication may have to be included in the information given to patients for their informed consent.

Immunophenotypic profile of biomarkers related to anti-apoptotic and neural development pathways in the Ewing's family of tumors (EFT) and their therapeutic implications

BACKGROUND

Ewing's family of tumors (EFT) comprises a broad spectrum of tumors composed of primitive committed cells with neuroectodermal capacity. The degree of neural differentiation within EFT, as measured with morphological features and expression of neural markers, delimits two members: Ewing's sarcoma (ES) and peripheral primitive neuroectodermal tumor (pPNET). Molecules such as c-kit and its ligand (Stem cell factor, SCF), CD95 (FAS), CD95L (FASL), IGF-IR, protect EFT cells from apoptosis, whereas c-erb-B2, erythropoietin (EPO) and its receptor (EPO-R) participate in the maturation of primitive committed neuroectodermal cells and in the normal embryonal brain development. The aim of the present study was to analyse the expression of these molecules in paraffin-embedded material from a series of EFT.

MATERIALS AND METHODS

Forty-five cases of EFT (23 typical ES, 4 atypical and 18 pPNET) were analysed following the immunohistochemical LSAB method, with antigen retrieval heating using an autoclave, citrate buffer pH 6.0 and the following primary antibodies: FAS (APO-CD 95), FAS-L, c-kit, SCF, IGF-IR and c-erbB2. The expression was evaluated independently by three of the authors and the final score (0 to 3+) was based on the intensity and percentage of positively stained cells. In a second cooperative analysis, tissues from 30 cases of EFT (15 typical, 3 atypical and 12 PNET) were immunostained with EPO and EPO-R.

RESULTS

High expression of c-kit/SCF (2+, 3+) was detected in 28/45 cases of EFT (62.2%), whereas FAS-FAS-L and IGF-IR were observed in 16/45 (37.7%) and 9/45 (20%), respectively. Regarding the neuroectodermal pathway, membranous and cytoplasmic expression of c-erb-B2 was observed in 9/45 (20%) EFT, regardless of the morphological and immunohistochemical expression of conventional neural markers. High expression of EPO and EPO-R was observed in 20/30 EFT (66.6%).

CONCLUSION

C-kit/SCF and EPO/EPO-R seem to participate in the pathway of anti-apoptotic and proliferative advantage, while c-erb-B2 does not play an important role in the neuroectodermal differentiation pathway in EFT cells.

Optimized preclinical models for human pancreatic adenocarcinoma therapy research

15019

Background: Efforts to find new therapies for human pancreatic ductal adenocarcinoma (PDAC) have not resulted in clear improvements on patient survival. Better knowledge of resistance mechanisms and redefiniton of molecular targets is essential to design more efficient therapies. The multifactorial origin of PDAC points to combined strategies as the therapy of choice, though the effective development of such strategies is hampered by the lack of optimal preclinical models. We have generated and validated optimized human PDAC models by direct implantation of fresh tumoral tissue into the pancreas of athymic mice. Methods: Thirteen pancreatic adenocarcinoma specimens from PDAC patients were obtained by surgical resection. From each specimen, several 10 mg-fragments were used to generate the corresponding intrapancreatic xenografted tumours. Eleven human PDAC orthotopic models have been successfully generated and perpetuated by succesive passages (up to 4). Histological and molecular analyses of both primary and xenografted tumors have been performed by tissue- array, western-blot and DNA sequentiation. Results: Initial engraftment rate ranged from 20 to 100% (mean 59%) and it improved with succesive passages (mean 76% at second and 90% at third generation). Ki67 expression and degree of differentiation in primary tumors correlated with xenograft growth kinetics. Furthermore, their spontaneous metastatic behaviour fairly reproduced the original patient dissemination patterns. Xenografted tumors kept the original architecture and expression patterns of common PDAC markers. Efficacy of several agents was tested on different xenografted tumors, validating this model and underlining its utility to define future therapeutic strategies for drug development and clinical trials. Conclusions: The orthotopic models described here are, probably, the closest resemblance to a patient clinical setting since they preserve human pancreatic structures, genotypic features and biological behaviour. From their use, biological relevant data could be drawn for future clinical trials and for testing new agents and new drug combinations since they represent, very likely, the most reliable animal models at present.

No significant financial relationships to disclose.

Prospective control trial of cancer ultrastaging in the left colon with sentinel lymph node

14547

Background: The use of the sentinel node lymph (SNL) in connection with colorectal cancer is a subject in which there has been some controversy. Methods: Prospective control trial of 60 patients with left colon cancer stage II. Methylene Blue® or Nanocoll® had been used to identify the SNL. The standard pathologic examination with hematoxylin and eosin (H&E) had been compared with the study of SNL with H&E and Cytokeratine CAM 5.2. Results: Identification of the SNL: 100%, 2.4 SNL detected in each patient. Nodal disease (N+) was found in 19 patients (31.7%), and 41 patients (68.3%) were classified as node-negative (N0). Hidden micrometastasis in the SNL were found in 9.7% (4/41) patients considered as N0 by conventional histopathology. However, in 17.7% (7/41) patients considered as N0 we found large cell clusters, contatining up to 10 tumor cells, falling short of the AJCC on cancer criteria, and were considered to have high- risk disease. Having applied both the SNL study and the standard pathologic examination the number of patients N+ has increased to 38.3% (23 patients), ultrastaging: 6.6% (p= ns). If the patients with large cell clusters in the SNL had been considered as N+ the number of N+ patients would have increased to 50%(30 patients), ultrastaging 18,3%(p=0,001). Conclusions: The combined nodal study (H&E + SNL) increased 6.6% the staging in our group, and it let to identify a group of patietnts N0 with high-risk tumor progression. If the large cell clusters in the SNL were considered as micrometastases disease the ultrastaging would have been 18.3%.The implications of large cell clusters prognosis is yet, unknown.

No significant financial relationships to disclose.

Subthalamic Stimulation and Neuronal Activity in the Substantia Nigra in Parkinson's Disease

High-frequency stimulation of the subthalamic nucleus (STN) is an effective treatment for severe forms of Parkinson's disease (PD). To study the effects of high-frequency STN stimulation on one of the main output pathways of the basal ganglia, single-unit recordings of the neuronal activity of the substantia nigra pars reticulata (SNr) were performed before, during, and after the application of STN electrical stimulation in eight PD patients. During STN stimulation at 14 Hz, no change in either the mean firing rate or the discharge pattern of SNr neurons was observed. STN stimulation at 140 Hz decreased the mean firing rate by 64% and the mean duration of bursting mode activity of SNr neurons by 70%. The SNr residual neuronal activity during 140-Hz STN stimulation was driven by the STN stimulation. How the decrease in rate and modification of firing pattern of SNr-evoked neural activity, during high-frequency STN stimulation, contribute to the improvement of parkinsonian motor disability remains to be elucidated.

The Role of Protein C Inhibitor in Human Reproduction

Protein C inhibitor (PCI) is a heparin-dependent serine protease inhibitor found in human plasma, urine, and other body fluids. In blood plasma, PCI is present at approximately 0.08 microM and inactivates activated protein C and other coagulation and fibrinolytic enzymes. In seminal plasma, PCI is present at 2.2 to 3.7 microM. The main sources of seminal PCI are the seminal vesicles, where it remains fully active. Following ejaculation, PCI completely looses its activity in approximately 2 hours, when it partially complexes with prostate-specific antigen, two plasminogen activators (urokinase-type and tissue-type plasminogen activators), and tissue kallikrein. PCI is also present in an active form in follicular fluid at approximately 0.1 microM. Purified functionally active human blood plasma-derived as well as inactive semen-derived PCI inhibited both binding and penetration of zona-free hamster oocytes by human sperm. The binding inhibition by PCI was dose dependent. A concentration of 0.04 microM PCI (approximately 100-fold lower than that present in seminal plasma) inhibited 50% of the binding and penetration ability. Given that capacitated sperm used for in vitro fertilization usually contains more than 0.05 microM of PCI, fertilization rates might be significantly reduced. All of these data suggest that PCI is involved in human reproduction at several steps, including the fertilization process.

Neurosurgery at an earlier stage of Parkinson disease: A randomized, controlled trial

BACKGROUND

Stimulation of the subthalamic nucleus is an effective treatment for advanced Parkinson disease (PD) and is currently performed after a mean disease duration of 14 years, when severe motor complications have resulted in marked loss of quality of life. We examined whether surgery at an early stage would maintain quality of life as well as improve motor function.

METHODS

Twenty patients with PD of short duration (time elapsed since first symptom +/- SD: 6.8 +/- 1.0 years) with mild to moderate motor signs (Unified Parkinson's Disease Rating Scale III "off" medication: 29 +/- 12) who responded well to levodopa treatment were included in pairs, matched for age, duration and severity of disease, and impairment in socioprofessional functioning. Patients were prospectively randomized to undergo bilateral subthalamic nucleus stimulation (n = 10) or receive optimized medical treatment (n = 10). Parkinsonian motor scores, quality of life, cognition, and psychiatric morbidity were assessed at inclusion and at 6, 12, and 18 months after randomization.

RESULTS

Quality of life was improved by 24% in surgical and 0% in nonsurgical patients (p < 0.05). After 18 months, the severity of parkinsonian motor signs "off" medication, levodopa-induced motor complications, and daily levodopa dose were reduced by 69%, 83%, and 57% in operated patients and increased by 29%, 15%, and 12% in the group with medical treatment only (p < 0.001). Adverse events were mild or transient, and overall psychiatric morbidity and anxiety improved in the surgical group.

CONCLUSIONS

Subthalamic nucleus stimulation should be considered a therapeutic option early in the course of Parkinson disease.

Circulating activated protein C is reduced in young survivors of myocardial infarction and inversely correlates with the severity of coronary lesions

BACKGROUND

Cardiovascular risk factors for myocardial infarction (MI) are less frequent in younger than in older MI survivors. Therefore, the thrombotic component of MI may play a more important role at a young age. As activated protein C (APC) provides systemic anticoagulant and anti-inflammatory protection, a low plasma APC level may be an arterial thrombotic risk factor.

AIM

To determine whether there is an association between reduced APC levels and early MI and severe coronary lesions.

METHODS

APC was measured in 231 young MI survivors and 231 controls.

RESULTS

Low APC levels were significantly associated with MI. Compared with the fourth quartile, the odds ratio (OR) for APC values in the first quartile was 3.7 [95% confidence interval (CI) = 2.1-6.4], and 3.2 (1.5-7.0) after adjustment for cardiovascular risk factors. Moreover, each decrease of 0.43 ng mL(-1) (1 SD) in APC increased the OR 1.7 times (1.4-2.2), and 1.5 times (1.2-1.9) after adjustment for cardiovascular risk factors. Low APC levels were also associated with the number of coronary arteries affected and with the severity of coronary lesions (P < 0.001).

CONCLUSIONS

There is a significant association between low circulating APC levels and both early MI and the extent and severity of coronary atherosclerosis, which might be related to the anticoagulant and anti-inflammatory properties of APC.

Phase I trial of gefitinib with concurrent radiotherapy and fixed dose-rate gemcitabine infusion, in locally advanced pancreatic cancer

4105

Background: Pancreatic cancers are resistant to radiotherapy (RT) and current chemotherapy agents. Epidermal growth factor receptor (EGFR) is over-expressed in pancreatic cancer and in vitro studies have shown that EGFR inhibitors can overcome radio- and chemo-resistance. The aim of the study was to determine the maximally tolerated dose of gefitinib, in combination with RT and gemcitabine for patients with locally advanced pancreatic carcinoma (LAPC). Methods: Eighteen patients with pathological proven LAPC, due to major vascular invasion based on helical computed tomography and endoscopic ultrasound, were entered. The targeted irradiated volume included the tumor and 2 cm-margin. Prophylactic irradiation of regional nodes was not allowed. Patients with >500 cc of planned tumor volume (PTV) were excluded. An initial cohort of 6 patients was treated with RT (45 Gy/25 fractions/5 weeks) plus concomitant gefitinib (250 mg/day). Successive cohorts of patients received 100, 150 and 200 mg/m2/day of gemcitabine in a 2 hour infusion over weeks 1,2,3,4, and 5 with gefitinib (250 mg/day) and RT. Gefitinib was continued after RT until progression. A pharmacodynamic study of angiogenic markers (VEGF and IL-8) was also performed. Results: Mean PTV was 293cc (range 137–462 cc). There were no dose-limiting toxicities on study. Common toxicities were mild neutropenia, asthenia, diarrhea, cutaneous rash and nausea/vomiting. One patient showed a partial response of 13 months in duration, and 7 patients showed disease stabilization. Median progression free survival (PFS) was 3.7 months and median overall survival (OS) was 7.5 months. No patients have a reduction in VEGF levels >50%. Reduction in VEGF serum levels >25% and IL-8 levels >50% had no impact on PFS and OS. Conclusion: Our results support thatthe combination of gefitinib, RT and gemcitabine showed an acceptable toxicity but with modest activity in LAPC.

[Table: see text]