Tycho Jan Zuzak

Resistance to TRAIL-induced apoptosis in primitive neuroectodermal brain tumor cells correlates with a loss of caspase-8 expression.

TNF-related apoptosis-inducing ligand (TRAIL) is a potent inducer of apoptosis in adult malignant glioma and various other human solid tumor models but not in normal tissues. To characterize the TRAIL death pathway in childhood primitive neuroectodermal brain tumor (PNET), 8 human PNET cell lines were tested for TRAIL-induced apoptosis. TRAIL-sensitivity of the PNET cell lines was correlated with mRNA expression levels of TRAIL, its agonistic (TRAIL-R1, TRAIL-R2) and antagonistic (TRAIL-R3, TRAIL-R4) receptors, cellular FLICE-like inhibitory protein (cFLIP), caspase-3 and caspase-8. Three of 8 PNET cell lines tested were susceptible to TRAIL-induced apoptosis. Sensitivity to TRAIL-induced apoptosis did not correlate with mRNA expression of TRAIL receptors or cFLIP. However, all TRAIL-sensitive PNET cell lines expressed caspase-8 mRNA and protein, while none of the five TRAIL-resistant PNET cell lines expressed caspase-8 protein. Treatment with the methyltransferase inhibitor 5-aza-2′-deoxycytidine restored mRNA expression of caspase-8 and TRAIL-sensitivity in formerly TRAIL-resistant PNET cells, suggesting that gene methylation inhibits caspase-8 transcription in these cells. We conclude, that loss of caspase-8 mRNA is an important mechanism of TRAIL-resistance in PNET cells. Treatment with recombinant soluble TRAIL, possibly in combination with methyltransferase inhibitors, represents a promising therapeutic approach for PNET that deserves further investigation.

Loss of caspase-8 mRNA expression is common in childhood primitive neuroectodermal brain tumour/medulloblastoma

Upon binding of tumour necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL), the agonistic TRAIL receptors DR4 and DR5 activate caspase-8 leading to apoptosis. In primitive neuroectodermal brain tumour (PNET) cell lines, TRAIL-induced apoptosis was recently shown to correlate with caspase-8 mRNA expression (Grotzer MA, Eggert A, Zuzak TJ, et al. Oncogene 2000, 19, 4604-4610). In this study, we analysed the expression of the TRAIL death pathway in 27 primary PNET/medulloblastoma. As shown by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR), all PNET/medulloblastoma evaluated expressed DR5, the adapter protein FADD and caspase-3, but only 48% expressed caspase-8. The mRNA expression of caspase-8 was significantly lower in primary PNET/medulloblastoma compared with normal brain samples. PCR revealed >75% methylation of the caspase-8 promoter region in three of seven PNET cell lines and in 55% of the primary PNET/medulloblastoma evaluated. In the PNET cell lines, the methylation status correlated with the caspase-8 mRNA expression. We conclude that loss of caspase-8 gene expression is common in PNET/medulloblastoma suggesting that suppression of death receptor induced apoptosis may play an important role in the pathogenesis of this common childhood brain tumour.

Use of complementary and alternative medicine by children in Europe: Published data and expert perspectives

INTRODUCTION Few data document the use of complementary and alternative medicine (CAM) in Europe, with even fewer investigating use by children. METHODS A narrative, non-systematic review of CAM use in Europe was performed by combining data from published surveys with expert perspectives. Limitations created by a lack of representative studies, varying definitions of CAM use, and what qualifies as CAM in different countries was partially overcome by integrating local experts to summarise information available only in the national language and provide their perspectives about CAM availability, quality, use and popularity in their countries using a semi-structured questionnaire. Local and international published surveys were summarised, and the prevalence of CAM use was extrapolated. RESULTS Data from 20 European countries were available, representing 69% of the European population. Some data about CAM use by the general population were available for 90% of the examined countries, whereas peer-reviewed published surveys were available for only 60%. We extrapolated that 56% (range: 10-90%, adjusted for population size) of the European population in general had used CAM at least once in the past year. Surveys in CAM use by children were available for 55% of the investigated countries. The extrapolated prevalence of CAM use by children in Europe was 52% (range: 5-90%, adjusted for population size). Paediatric CAM experts reported an increasing awareness for and use of CAM in healthcare institutions. CONCLUSION This precursor for further surveys indicates that CAM appears to be popular not only among adults in Europe, but also for children. Development of a pan-European definition of CAM use and CAM therapies are required to achieve surveys comparable between European countries. Additionally, more research investigating the efficacy and potential adverse effects of CAM therapies is needed because of increasing CAM use by children in Europe.

Use of complementary and alternative medicine by patients presenting to a paediatric Emergency Department

Although the popularity of complementary and alternative medicine (CAM) has risen in the last decade, information about its use by paediatric patients presenting to an Emergency Department is still sparse. We report here the results of a cross-sectional survey of paediatric patients presenting to an urban, tertiary paediatric Emergency Department between October 2006 and March 2007. In total, 1143 questionnaires (68% of those distributed) were completed and available for analysis. Of these, 58% (n = 665) of all respondents admitted that their child had received some form of CAM therapy, while 25% (n = 291) admitted that their child was receiving CAM for the present illness. In 31% of the respondents (n = 354), CAM had been prescribed by a physician, while 50% (n = 575) used CAM as self-medication. Patients presented to the Emergency Department mostly because of an infection (42% of total; 29% of these used CAM) or a trauma (38% of total; 19% of these used CAM). Parents of CAM-users were significantly older, more often born in Switzerland and had significantly higher school education than those of the non-users. Nearly two-thirds of the administered CAM therapies were not prescribed by a physician, and 50% of the families using CAM did not discuss this with their general practitioner. Parental requirements implied that medical professionals on a paediatric Emergency Department should know the effects and side-effects of CAM therapies and even be able to recommend them. The study population, even trauma patients, frequently used CAM. The use of CAM is characterised by a high rate of self-medication and the exclusion of the physicians from the decision-making process. The parents of paediatric patients frequently demand that CAM be considered as a possible treatment option and wish to have an open discussion with the medical professionals on this topic.

MicroRNA-21 suppression impedes medulloblastoma cell migration.

Medulloblastoma (MB), the most common malignant brain tumour in children, is characterised by a high risk of leptomeningeal dissemination. But little is known about the molecular mechanisms that promote cancer cell migration in MB. Aberrant expression of miR-21 is recognised to be causatively linked to metastasis in a variety of human neoplasms including brain tumours; however its function in MB is still unknown. In this study we investigated the expression level and the role of miR-21 in MB cell migration. miR-21 was found to be up-regulated, compared to normal cerebellum, in 29/29 MB primary samples and 6/6 MB-derived cell lines. Inverse correlation was observed between miR-21 expression and the metastasis suppressor PDCD4, while miR-21 repression increased the release of PDCD4 protein, suggesting negative regulation of PDCD4 by miR-21 in MB cells. Anti-miR-21 decreased protein expression of the tumour cell invasion mediators MAP4K1 and JNK, which are also known to be negatively regulated by PDCD4, and down-regulated integrin protein that is essential for MB leptomeningeal dissemination. Moreover miR-21 knockdown in MB cells increased the expression of two eminent negative modulators of cancer cell migration, E-Cadherin and TIMP2 proteins that are known to be positively regulated by PDCD4. Finally and importantly, suppression of miR-21 decreased the motility of MB cells and reduced their migration across basement membranes in vitro. Together, these compelling data propose miR-21 pathway as a novel mechanism impacting MB cell dissemination and raises the possibility that curability of selected MB may be improved by pharmaceutical strategies directed towards microRNA-21.

Outcome in children with brain tumours diagnosed in the first year of life: long-term complications and quality of life

Objective: To study the outcome in children with brain tumours diagnosed in the first year of life, we followed up 27 consecutive children who were diagnosed between 1980 and 2005 in a single institution. Methods: Tumour control and neurological, endocrine and cognitive complications and their impact on behavioural and emotional adjustment and health-related quality of life (HRQoL) were comprehensively assessed in 11 survivors (mean follow-up time 12.3 years). Results: Persistent neurological complications occurred in 9/11 patients, endocrine and growth complications in 4/11, and cognitive deficits leading to school problems/impaired choice of occupation in 8/10. Behavioural and psychological adjustment problems were reported by 4/6 patients and 7/10 parents. HRQoL as rated by patients and their parents was considerably lower than that of healthy controls. In comparison with healthy controls, social functioning was rated by the patients and the parents as the QoL dimension most affected. HRQoL was lowest for patients with high-grade tumour histology and more intense therapy. Conclusion: Long-term survivors of brain tumours diagnosed in the first year of life are not only at great risk of neurological and cognitive complications, but also of social isolation thereby substantially decreasing self-rated HRQoL.

Expression of Apo-3 and Apo-3L in primitive neuroectodermal tumours of the central and peripheral nervous system

Deregulation of apoptosis has been implicated in the pathogenesis, spontaneous regression and treatment resistance of neuroblastoma. A newly recognised member of the tumour necrosis factor (TNF)-family of death receptors known as Apo-3 has been mapped to human chromosome 1p36.3, a region commonly deleted in aggressive neuroblastoma. Based on its localisation and function, Apo-3 is a candidate for the putative neuroblastoma tumour suppressor gene. Therefore we analysed mRNA expression of the Apo-3 receptor/ligand (Apo-3/Apo-3L) system in a representative panel of 18 neuroblastoma cell lines, 41 primary neuroblastoma and 13 ganglioneuromas/ganglioneuroblastomas by semi-quantitative RT-PCR. We compared the level of expression with the well-established prognostic factors age, stage, histology, MYCN-amplification and TrkA expression, as well as outcome. For comparison, we studied Apo-3/Apo-3L expression in 27 central nervous system (CNS) primitive neuroectodermal tumours/medulloblastomas (PNET/medulloblastoma) and in six normal brain samples. Neuroblastoma cell lines with 1p deletion and MYCN-amplification expressed significantly lower levels of Apo-3 (P=0.009 and P=0.03, respectively) compared with neuroblastoma cell lines without 1p deletion or MYCN-amplification. The mean expression level of Apo-3L was significantly higher in ganglioneuromas/ganglioneuroblastomas compared with neuroblastomas (P=0.001) and in normal brain compared with PNET/medulloblastoma (P<0.0001). Expression of Apo-3L was significantly associated with survival in neuroblastomas (P<0.049) and in PNET/medulloblastomas (P=0.01). Expression of Apo-3 was significantly associated with survival in PNET/medulloblastomas (P=0.03). Thus, the Apo-3 receptor/ligand system might be involved in the regulation of apoptosis in neuroblastomas and PNET.

Complementary and alternative medicine in paediatrics in daily practice—A European perspective

INTRODUCTION Complementary and alternative medicine (CAM) is used by both adults and children in Europe. Diverse cultural, ethnic and historical preconditions in European countries result in broad differences between the types of CAM practiced, prevalence of CAM use and integration in the health system. To date, no survey of CAM availability to paediatric patients in Europe exists. METHODS We present an overview of CAM integration within the different levels of the European paediatric health systems as a narrative review. Paediatric CAM specialists in 20 European countries provided information about CAM integration in their countries in semi-structured interviews. RESULTS Data from 20 European countries were available, representing 68% of the European population. CAM is offered in private practices in all 20 (100%) countries, and 80% described some form of CAM training for health professionals. While CAM is offered in outpatient clinics treating adults in 80% of these countries, only 35% offer CAM in paediatric outpatient clinics. Dedicated CAM inpatient wards exist in 65% of the countries for adults, but only in Germany and the Netherlands for children. Groups conducting some CAM research or CAM research focussed on paediatrics exist in 65% and 50% of the 20 countries, respectively. Homeopathy, acupuncture and anthroposophic medicine were most often named. CONCLUSION Every child in Europe has access to CAM treatment, mainly in private practices, whereas CAM outpatient clinics and inpatient services for children are rare. This is in contrast to adult treatment facilities, many of which offer CAM services, and the high percentage of European children using CAM.

Accidental intakes of remedies from complementary and alternative medicine in children—analysis of data from the Swiss Toxicological Information Centre

The use of complementary and alternative medicine (CAM) in Switzerland is rather high, and therefore, the occurrence of accidental intakes of CAM remedies by children and associated intoxications is to be expected. In the present study, the inquiries to the Swiss Toxicological Information Centre that took place from 1998 until 2007 and concerned accidental, unintended intakes of CAM remedies by children were analysed. Inquiries for information were performed by concerned care-givers, physicians, pharmacists and others in case of acute accidental intake of CAM remedies. Feedbacks from physicians about paediatric patients with acute intoxication possibly associated with the accidental ingestion of CAM remedies were as well considered. During the study period, 3,158 accidental intakes of CAM remedies (1,015 of herbal and 2,143 of homeopathic remedies) were reported, corresponding to 8.6% of all reported accidental intakes of pharmaceutical products by children. No significant increase of the yearly number of accidental intakes of CAM remedies was detected during the study period. There was no accidental intake of CAM remedies leading to severe signs or symptoms. Concerning the herbal remedies, three intoxications of moderate and 28 of minor severity were reported. Nine children with intoxication from homeopathic remedies were reported, with minor symptoms only. All other accidental intakes of CAM remedies did not lead to intoxications and evolved without manifestations. The data show that accidental, unintended intake of CAM remedies happened in children, but developed mostly harmlessly. Comparing herbal with homeopathic remedies, accidental intakes with homeopathic remedies were more common, but intoxications associated with manifestations were observed more frequently with herbal remedies.

Contributing factors and outcomes of treatment refusal in pediatric oncology in Germany.

In Germany, about 1,800 new cases of pediatric cancer under 15 years of age are diagnosed each year and survival rates approach 80%. Although treatment is covered by health insurance and is thus available for all patients at no cost, treatment refusal and treatment discontinuation have been observed. However, no data providing numbers and outcomes for developed countries have been published thus far.