Extended induction chemotherapy does not improve the outcome for high-risk neuroblastoma patients: results of the randomized open-label GPOH trial NB2004-HR.

BACKGROUND: Long-term survival of high-risk neuroblastoma patients is still below 50% despite intensive multimodal treatment. This trial aimed to address whether the addition of two topotecan-containing chemotherapy courses compared to standard induction therapy improves event-free survival (EFS) of these patients. PATIENTS AND METHODS: An open-label, multicenter, prospective randomized controlled trial was carried out at 58 hospitals in Germany and Switzerland. Patients aged 1-21 years with stage 4 neuroblastoma and patients aged 6 months to 21 years with MYCN-amplified tumors were eligible. The primary endpoint was EFS. Patients were randomly assigned to standard induction therapy with six chemotherapy courses or to experimental induction chemotherapy starting with two additional courses of topotecan, cyclophosphamide, and etoposide followed by standard induction chemotherapy (eight courses in total). After induction chemotherapy, all patients received high-dose chemotherapy with autologous hematopoietic stem cell rescue and isotretinoin for consolidation. Radiotherapy was applied to patients with active tumors at the end of induction chemotherapy. RESULTS: Of 536 patients enrolled in the trial, 422 were randomly assigned to the control arm (n = 211) and the experimental arm (n = 211); the median follow-up time was 3.32 years (interquartile range 1.65-5.92). At data lock, the 3-year EFS of experimental and control patients was 34% and 32% [95% confidence Interval (CI) 28% to 40% and 26% to 38%; P = 0.258], respectively. Similarly, the 3-year overall survival of the patients did not differ [54% and 48% (95% CI 46% to 62% and 40% to 56%), respectively; P = 0.558]. The response to induction chemotherapy was not different between the arms. The median number of non-fatal toxicities per patient was higher in the experimental group while the median number of toxicities per chemotherapy course was not different. CONCLUSION: While the burden for the patients was increased by prolonging the induction chemotherapy and the toxicity, the addition of two topotecan-containing chemotherapy courses did not improve the EFS of high-risk neuroblastoma patients and thus cannot be recommended. CLINICAL TRIALS. GOV NUMBER: NCT number 03042429.

Laparoscopic Adrenalectomy is Feasible for Suspected Adrenal Tumors in Children Younger than 24 Months of Age - But is it Always Justified?

INTRODUCTION: Tumors of the adrenal gland are rare in children younger than 24 months of age. While neuroblastomas are most important in this age group, adrenal hemorrhage and other tumors are sometimes difficult to distinguish. Harvesting biopsies is mandatory in these young patients to obtain information on molecular markers, namely, MYCN and 1p deletion. PATIENTS: Between 03/2012 and 10/2013, 11 patients younger than 24 months of age with suspicious adrenal tumors were operated on laparoscopically. METHODS: The diagnostic workup was coordinated by our pediatric oncologists according to the terms of the NB2004 trial protocol. RESULTS: 9 out of 11 had a diagnosis of neuroblastoma, the others were adenoma respective complete necrosis of the adrenal gland. All of the neuroblastomas were negative for both MYCN amplification and 1p deletion. A complete resection was successful in 9 out of 11 cases. 3 complications occurred, 1 major and 2 minor. DISCUSSION AND CONCLUSION: Behind the recognition that laparoscopic adrenalectomy is technically feasible, the fact that all neuroblastomas were negative for MYCN amplification and 1p deletion raises the issue of whether biopsy is mandatory for risk stratification in this age group.

Image-defined Risk Factors Correlate with Surgical Radicality and Local Recurrence in Patients with Neuroblastoma.

BACKGROUND: Neuroblastoma is the second most common solid pediatric tumor and the most common cancer to be detected in children younger than 12 months of age. To date, 2 different staging systems describe the extent of the disease: the International Neuroblastoma Staging System (INSS) and the International Neuroblastoma Risk Group Staging System (INRGSS). The INRGSS-system is characterized by the presence or absence of so called image-defined risk factors (IDRFs), which are described as surgical risk factors. We hypothesized that IDRFs correlate with surgical complications, surgical radicality, local recurrence and overall survival (OS). PATIENTS AND METHODS: Between 2003 and 2010, 102 patients had neuroblastoma surgery performed in our department. We analyzed medical records for IDRF-status and above named data. RESULTS: 16 patients were IDRF-negative, whereas 86 patients showed one or more IDRF. Intra- or postoperative complications have been reported in 21 patients (21%). 19 of them showed one or more IDRF and 2 patients were IDRF-negative (p=n.s.). Patients who suffered from intra- or postoperative complications demonstrated a decreased OS (p=0.011). Statistical analysis revealed an inverse correlation between the extent of macroscopical removal and IDRF-status (p=0.001). Furthermore, the number of IDRFs were associated with a decreased likelihood of radical tumor resection (p<0.001). 19 patients had local recurrence; all of them were IDRF-positive (p=0.037). CONCLUSIONS: Pediatric surgeons should consider IDRFs as a useful tool for risk assessment and therefore planning for neuroblastoma surgery.

Incidence, Trends, and Survival of Children With Embryonal Tumors.

BACKGROUND: Central nervous system (CNS) and non-CNS embryonal tumors occur principally in children and are rarely seen in adults. The incidence rates for rare entities such as atypical teratoid/rhabdoid tumors (AT/RT) or primitive neuroectodermal tumors in the CNS are rarely published. Incidence rates for certain subgroups, such as hepatoblastomas, have been increasing in some countries. METHODS: Data of 8337 embryonal tumors, registered in children (0-14 years) between 1991 and 2012 (for AT/RT 2000-2012) in the population-based German Childhood Cancer Registry with complete national coverage were analyzed for incidence rates, time trends, and survival. RESULTS: For most entities, the incidence rates were the highest for children <1 year. An important exception was medulloblastomas, which occurred mainly in 1- to 9-year-olds. Neuroblastomas and ganglioneuroblastomas as well as Wilms tumors (nephroblastomas) had the highest age standardized incidence rates (13.7 and 9.4 per million, respectively). A statistically significant increasing trend for hepatoblastomas (annual average percent change 4.6%) was detected. The survival probabilities varied between the diagnostic groups: primitive neuroectodermal tumors and AT/RT had the lowest and retinoblastomas the highest. The survival was dependent on the age at diagnosis, the most extreme examples being neuroblastomas, for which the survival probability declined steeply for children ≥1 year and medulloblastomas, for which the highest survival was seen for 10- to 14-year-olds. CONCLUSIONS: This study presents a comprehensive overview of pediatric embryonal tumors from a well-established, complete nationwide cancer registry. Significant increasing trend for hepatoblastomas was detected for the first time in Europe.

Pretreatment for bilateral nephroblastomatosis is an independent risk factor for progressive disease in patients with stage V nephroblastoma.

BACKGROUND: Treatment of stage V nephroblastoma is less established and more complex than in unilateral nephroblastoma. METHODS: Retrospective analysis of 121 consecutive patients with stage V nephroblastoma registered from January 1989 to May 2005. Registration, prospective data collection and treatment were carried out within the framework of 3 consecutive SIOP/GPOH-nephroblastoma-trials. RESULTS: 19 patients had metastasis and 29 syndromes at diagnosis. 13 patients had been pretreated for bilateral nephroblastomatosis. 1 patient was not treated and 17 patients had upfront surgery. Preoperative treatment duration ranged from 1-12 weeks (n=103). 1-3 preoperative treatment-cycles resulted in average tumor-volume-reduction of 45%. 1 patient underwent bilateral nephrectomy. 52% of the patients had 2 functioning kidneys after the end of treatment. 20 patients had died after mean follow-up of 8.6 years. 5y-Progression-Free (PFS) and Overall-Survival (OS) were excellent for patients having a localized disease without pretreatment for nephroblastomatosis (5yPFS/OS: 80±4%/93±3%). Metastasis at diagnosis (51±12%/56±12%; p=0.003) and pretreatment for nephroblastomatosis (37±14%/67±13%; p<0.001) were associated with significantly poorer outcome. Cox-regression analysis revealed an independent influence of pretreatment for nephroblastomatosis, metastasis and syndromes on PFS. The latter 2 as well as anaplasia and age (<2 years or >3 years) had an independent influence on OS. CONCLUSIONS: Pretreatment for nephroblastomatosis, metastasis and syndromes are independent risk factors. 1-3 preoperative treatment-cycles are sufficient to achieve save nephron-sparing-surgery in most patients.

Testicular sex cord stromal tumors: analysis of patients from the MAKEI study.

BACKGROUND: In children and adolescents, testicular sex cord stromal tumors (TSCSTs) are rare. There is only limited information available regarding their clinical presentation, biology, and prognosis. METHODS: Between 1993 and 2009, 42 patients were prospectively reported to the cooperative MAHO and MAKEI studies on childhood germ cell tumors. Based on standardized documentation, data on epidemiology, clinical presentation, diagnostic features, histopathological differentiation, therapy, and follow-up were evaluated. RESULTS: During the study period, a gradual increase of the documentation of these rare tumors was observed. Palpable, indolent testicular swelling was the most common clinical finding. In three patients, retention of the testis was observed. Two patients showed sexual precocity, and one patient showed a 45X/46XY mosaic. Juvenile granulosa cell tumors (n = 16) and Sertoli cell tumor (n = 15) were the leading histopathological subtypes. The first were commonly diagnosed during the first weeks of life (median age: 6(0-162) days, the latter during infancy (median 7(0-14) months, P < 0.05). Other histological diagnoses included Leydig cell and Large Cell Calcifying Sertoli cell tumors (both n = 3) and not-otherwise-specified TSCSTs (n = 5), which were diagnosed during childhood and adolescence. All tumors were limited to the testis; there were no metastases. Treatment was surgical, only. After a median follow-up of 3.8 years, no relapse was observed. CONCLUSIONS: Diagnosis and therapy of testicular tumors should be planned in accordance with the recommendations of the respective childhood germ cell tumor protocols. High inguinal orchiectomy is safe and constitutes definitive therapy. Diagnostic work-up and follow-up should also consider potentially associated tumor predisposition syndromes.

RIP1 is required for IAP inhibitor-mediated sensitization for TRAIL-induced apoptosis via a RIP1/FADD/caspase-8 cell death complex.

Inhibitor of apoptosis (IAP) proteins represent promising therapeutic targets due to their high expression in many cancers. Here, we report that small-molecule IAP inhibitors at subtoxic concentrations cooperate with monoclonal antibodies against TRAIL receptor 1 (Mapatumumab) or TRAIL-R2 (Lexatumumab) to induce apoptosis in neuroblastoma cells in a highly synergistic manner (combination index <0.1). Importantly, we identify receptor-activating protein 1 (RIP1) as a critical mediator of this synergism. RIP1 is required for the formation of a RIP1/FADD/caspase-8 complex that drives caspase-8 activation, cleavage of Bid into tBid, mitochondrial outer membrane permeabilization, full activation of caspase-3 and caspase-dependent apoptosis. Indeed, knockdown of RIP1 abolishes formation of the RIP1/FADD/caspase-8 complex, caspase activation and apoptosis upon combination treatment. Similarly, inhibition of RIP1 kinase activity by Necrostatin-1 inhibits IAP inhibitor- and TRAIL receptor-triggered apoptosis. In contrast, overexpression of the dominant-negative superrepressor IκBα-SR or addition of the tumor necrosis factor (TNF)α-blocking antibody Enbrel do not interfere with cotreatment-induced apoptosis, pointing to a nuclear factor-κB- and TNFα-independent mechanism. Of note, IAP inhibitor also sensitizes primary cultured neuroblastoma cells for TRAIL receptor-mediated loss of viability, underscoring the clinical relevance. By identifying RIP1 as a critical mediator of IAP inhibitor-mediated sensitization for Mapatumumab- or Lexatumumab-induced apoptosis, our findings provide new insights into the synergistic interaction of IAP inhibitors together with TRAIL receptor agonists.

Surgical aspects in the treatment of adrenocortical carcinomas in children: data of the GPOH-MET 97 trial.

Adrenocortical carcinomas (ACCs) are a rare entity, with an incidence of 1.5 per million population per year. The prognosis of ACC is poor. Complete surgical resection is essential for a curative approach and significantly determines overall prognosis. Tumor resection is sophisticated and complicated by the vulnerability of the tumor and its invasive growth. Chemotherapy and Mitotane are additional therapeutic approaches that are combined with surgery in an interdisciplinary strategy. In this study, 59 patients between 2 months and 18 years of age with histologically verified ACC were analyzed retrospectively with respect to oncosurgical aspects. Patients were registered in the GPOH-MET 97 trial of the Society of Pediatric Oncology and Haematology. Preoperative management, factors influencing surgical severity, and operative complications were assessed.The gender ratio was 1:2 (m:f). A total of 58 patients showed increased hormonal activity and associated clinical signs of hormonal excess. Tumor volume was ≥ 300 mL in 25 patients. These patients showed an increased rate of operative complications and a poorer overall survival (OS) rate (p<0.01). A total of 14 patients showed metastatic spread, particularly to the lungs and lymph nodes. Biopsy of the tumor was performed in 12 patients. Tumor rupture occurred in 11 patients. Preoperative biopsy and/or experienced tumor rupture were associated with poorer OS rate. R2 resection only was achievable in 5 patients, and surgery was not feasible in 3 patients.In conclusion, since most of the pediatric ACC are hormone active and can be diagnosed clinically, the need of a tumor biopsy has to be discussed critically. Thorough pre- and perioperative management is essential for oncosurgical success.

Malignant pancreatic tumors in children and young adults: evaluation of 228 patients identified through the Surveillance, Epidemiology, and End Result (SEER) database.

BACKGROUND: Malignant pancreatic tumors are rare in young patients, few epidemiologic data are available. We reviewed prognostic factors and outcome of 228 patients <30 years with malignant pancreatic tumors identified through the U.S. National Cancer Institute's SEER (Surveillance, Epidemiology, and End Results) Public-use Database from 1973 to 2004. METHODS: Cases were grouped using the ICD-O-3. 5-year overall survival (OAS) was assessed by gender, ethnicity, SEER stage, and 5-year age intervals using univariate and Cox regression analysis. RESULTS: 228 patients with malignant pancreatic tumors were identified, resulting in an incidence of 0.46/million (100 carcinomas, 85 endocrine tumors, 8 solid pseudopapillary neoplasms (SPN), 11 pancreatoblastomas) in the USA. OAS was worse in males than females (37% vs. 55%, p=0.005). OAS according to stage was 87%, 68%, 21% for local (n=54), regional (n=42), distant metastatic disease (n=108), respectively. OAS of patients with carcinoma was 33%, endocrine tumors 58%, SPNs 88%, pancreatoblastomas 66%. Cox regression revealed stage (p=< 0.001), histology (p=< 0.001), age group (p=0.05) to be independent prognostic factors. CONCLUSION: Malignant pancreatic tumors are extremely rare in children and young adults. Entities change over the age groups towards more carcinomas with worse outcome in older patients. Tumor stage, histology and age group are important predictors for outcome. International collaboration is needed to learn more about pediatric pancreatic tumors.

Re-operations for Hirschsprung's disease: long-term complications.

INTRODUCTION: In some patients with Hirschsprung's disease (HD), the initial surgical procedure fails, and the patients suffer from repeated or persistent symptoms. These patients complain of severe inflammation, intestinal obstruction, fecal or urinary incontinence, abdominal pain or dystrophy. However, little data has been published on the long-term follow-up results after re-operations for HD. MATERIALS AND METHODS: We followed 8 cases between 2004 and 2006, of complicated HD requiring repeated surgery and recorded prior procedures, histological results, indications for re-operation, postoperative follow-up as well as long-term clinical outcomes including stool patterns, nutrition and micturition. RESULTS: The follow-up period ranged from 3.0 to 5.5 years (mean: 4.4 years). Indications for repeat procedures were as follows: blind rectal pouch after a Duhamel operation (n = 2), persistent aganglionosis (n = 4), long-segment stenosis (n = 1) after a Rehbein operation, and anal stenosis following TERPT (transanal endorectal pull-through) (n = 1). In one patient who had a Duhamel-Martin operation, extirpation of the rectum and a definitive terminal ileostomy was necessary. A Duhamel procedure was performed in five patients with a primary Rehbein and 1 patient with a primary Duhamel operation. Complete stool continence was achieved in 4 patients. Partial fecal incontinence persisted in one patient with associated trisomy 21. 1 patient with total colonic aganglionosis and 1 patient with a pelvic fistula and a previous subtotal colectomy reported soiling 1-2 times per week after a repeat operation. 4 patients in our series experienced postoperative complications following repeated surgery [perianal ulceration (n = 2), repeated botulinum toxin injection for sphincter achalasia (n = 1) and functionally impaired colonic transit without stenosis (n = 1)]. Micturition was normal in 7 patients, 1 patient with associated trisomy 21 was partially continent, and 1 patient reported infrequent urge incontinence. CONCLUSIONS: All patients improved after further surgical intervention. However, resolution of their symptoms was delayed and partial stool incontinence or soiling persisted in 3 patients. Most complications leading to repeat procedures are preventable, especially residual aganglionosis. Therefore, great efforts should be made to minimize complications when planning and performing the primary surgery.

Update on relapses in unilateral nephroblastoma registered in 3 consecutive SIOP/GPOH studies - a report from the GPOH-nephroblastoma study group.

INTRODUCTION: Treatment and stratification of progressive/relapsed unilateral nephroblastoma (PD) has significantly evolved over the last 20 years. Early PD (≤ 6 months), initial high risk histology, local stage III, multiple site PD and stage IV have been implemented as high risk classification factors and novel drugs have been introduced. PATIENTS AND METHODS: We analysed all 251 patients having had a unilateral nephroblastoma (Stage I-IV) and progressive disease who had been treated according to SIOP9/GPO (n = 77), SIOP93-1/GPOH (n = 93) and SIOP2001/GPOH (n = 81) initially. RESULTS: 3y-overall survival (OS) increased from 43% to 61% and 59% respectively (both p<0.01). 3y-OS for localized stage I-III rose from 43% to 65% and 68% respectively while only little improvement can be seen for initial stage IV patients with 43%, 53% and 44% respectively. Multivariate analysis confirmed high risk histology, local stage III, shorter time to PD, combined relapse as independent risk factors. 26 patients had received high-dose chemotherapy showing 64% 3y-OS compared to 54% for all non-transplanted (p=0.11). CONCLUSION: Structuring the treatment of progressive nephroblastoma as well as introducing new drugs have improved the outcome significantly. However improvement is depending on the specific risk profile. Very high risk tumours are often resistant to conventional treatment, hence an international uniform treatment concept is needed to achieve conclusive results in this small group.

PI3K inhibitors prime neuroblastoma cells for chemotherapy by shifting the balance towards pro-apoptotic Bcl-2 proteins and enhanced mitochondrial apoptosis.

We recently identified activation of phosphatidylinositol 3'-kinase (PI3K)/Akt as a novel predictor of poor outcome in neuroblastoma. Here, we investigated the effect of small-molecule PI3K inhibitors on chemosensitivity. We provide first evidence that PI3K inhibitors, for example PI103, synergize with various chemotherapeutics (Doxorubicin, Etoposide, Topotecan, Cisplatin, Vincristine and Taxol) to trigger apoptosis in neuroblastoma cells (combination index: high synergy). Mechanistic studies reveal that PI103 cooperates with Doxorubicin to reduce Mcl-1 expression and Bim(EL) phosphorylation and to upregulate Noxa and Bim(EL) levels. This shifted ratio of pro- and antiapoptotic Bcl-2 proteins results in increased Bax/Bak conformational change, loss of mitochondrial membrane potential, cytochrome c release, caspase activation and caspase-dependent apoptosis. Although Mcl-1 knockdown enhances Doxorubicin- and PI103-induced apoptosis, silencing of Noxa, Bax/Bak or p53 reduces apoptosis, underscoring the functional relevance of the Doxorubicin- and PI103-mediated modulation of these proteins for chemosensitization. Bcl-2 overexpression inhibits Bax activation, mitochondrial perturbations, cleavage of caspases and Bid, and apoptosis, confirming the central role of the mitochondrial pathway for chemosensitization. Interestingly, the broad-range caspase inhibitor zVAD.fmk does not interfere with Bax activation or mitochondrial outer membrane permeabilization, whereas it blocks caspase activation and apoptosis, thus placing mitochondrial events upstream of caspase activation. Importantly, PI103 and Doxorubicin cooperate to induce apoptosis and to suppress tumor growth in patients' derived primary neuroblastoma cells and in an in vivo neuroblastoma model, underlining the clinical relevance of the results. Thus, targeting PI3K presents a novel and promising strategy to sensitize neuroblastoma cells for chemotherapy-induced apoptosis, which has important implications for the development of targeted therapies for neuroblastoma.

Betulinic acid induces apoptosis and inhibits hedgehog signalling in rhabdomyosarcoma.

BACKGROUND: Rhabdomyosarcoma (RMS) is the most common soft-tissue sarcoma in childhood with the ability to resist apoptosis by the activation of survival promoting and anti-apoptotic proteins. METHODS: Efficacy of the apoptosis-inducing agent betulinic acid (BA) was determined in RMS cell cultures and in vivo by measuring cell viability, survival, apoptosis, hedgehog signalling activity, and neovascularisation. RESULTS: Betulinic acid had a strong cytotoxic effect on RMS cells in a dose-dependent manner. The BA treatment caused a massive induction of apoptosis mediated by the intrinsic mitochondrial pathway, which could be inhibited by the broad-range caspase inhibitor zVAD.fmk. Exposure of hedgehog-activated RMS-13 cells to BA resulted in a strong decrease in GLI1, GLI2, PTCH1, and IGF2 expression as well as hedgehog-responsive luciferase activity. Intraperitoneal injection of 20 mg BA per kg per day significantly retarded growth of RMS-13 xenografts in association with markedly higher counts of apoptotic cells and down-regulation of GLI1 expression compared with control tumours, while leaving microvascular density, cell proliferation, and myogenic differentiation unaffected. CONCLUSION: Our data show that induction of apoptosis and inhibition of hedgehog signalling are important features of the anti-tumourigenic effect of BA in RMS and advices this compound for the use in a multimodal therapy of this highly aggressive paediatric tumour.

Early and long term outcome in children with esophageal atresia treated over the last 22 years.

BACKGROUND: The survival of infants born with esophageal atresia (EA) is > 90% at present. The purpose of this study was to evaluate early complications and long term outcome in children with EA treated at our institution. METHODS AND PATIENTS: Retrospective analysis of 111 children with EA undergoing repair of EA or tracheoesophageal fistula (TEF). Assessment of early and intermediate complications as well as long term morbidity and mortality. RESULTS: Primary anastomosis was performed in 90 (81%) and secondary anastomosis in 7 patients (6%). Gastric transposition was carried out in 14 children (13%). The postoperative mortality was 14/111 (12.6%) and could be estimated by the Spitz classification. At the age of 10 years, 33 patients (72%) were swallowing without problems, 39 children (85%) were eating at least most of the time with pleasure but 19 children (41%) had a body weight less than the 25 (th) percentile. Staged repair by gastric transposition resulted in the least amount of motility dysfunction. Long-term respiratory morbidity was high. CONCLUSION: The survival of children with EA has improved in the last two decades. For risk assessment the Spitz' classification is valid. Long term gastrointestinal and respiratory morbidity remains high. In children with long-gap EA gastric transposition performed as a staged procedure has satisfactory results and seems superior to techniques preserving the native esophagus.

Hepatocyte growth factor protects hepatoblastoma cells from chemotherapy-induced apoptosis by AKT activation.

Hepatocyte growth factor/scatter factor (HGF) is a ubiquitously expressed molecule that elicits pleiotropic functions on epithelial cells, including mitogenic, motogenic, differentiating, angiogenic and morphogenic effects. In hepatoblastoma (HB), post-operative residual tumor growth and tumor recurrences are often associated with markedly elevated serum levels of HGF, suggesting a link between this molecule and tumor malignancy. Here, we demonstrate that HGF has no impact on overall cell viability and proliferation of HB cells, although signal transduction occurs downstream of HGF, such as c-Met phosphorylation, activation of phosphoinositide 3-kinase (PI3K)/AKT and mitogen-activated protein kinase (MAPK)/ERK-1/2 signaling. Instead of being mitogenic, HGF confers anti-apoptotic properties upon serum starvation and moreover protects HB cells against strong apoptotic inducers such as cisplatin and camptothecin, thereby contributing to chemotherapeutic resistance. This effect is mainly dependent on the PI3K/AKT signaling pathway, since inhibition by wortmannin resulted in abrogation of HGF-mediated survival, whereas inhibition of the MAPK pathway had no effect. Together, these findings highlight the importance of HGF in tumor cell survival and suggest that HGF and its cognate receptor c-Met should be considered as a candidate for combined therapeutic strategies of advanced pediatric liver tumors.

Association of the interleukin-23 receptor gene variant rs11209026 with Crohn's disease in German children.

AIM: Genome-wide association studies have described variants within the interleukin-23 receptor (IL23R) locus to be associated with Crohn's disease (CD) and ulcerative colitis (UC). We investigated the association of rs11209026 (p.Arg381Gln) and rs7517847 (c.799-3588T>G) into German paediatric inflammatory bowel disease (IBD) patients and analysed IL23R transcriptional activity in colonic tissues. METHODS: The rs11209026 and rs7517847 nucleotide substitutions were determined in 353 German children with IBD (221 CD, 132 UC) and 253 controls using pre-designed TaqMan((R)) SNP genotyping assays. In selected IBD patients and controls, IL23R mRNA expression was measured using real-time PCR. RESULTS: The prevalence of the rs11209026 A allele was lower in CD patients, but not in UC patients, when compared with controls (1.8% vs 7.1%, p < 0.01). The rs7517847 variant, in contrast, was associated neither with CD nor with UC. IL23R expression was variable in IBD patients compared with controls without significant overexpression or downregulation. CONCLUSION: Our study provides additional support for the strong protection of the rs11209026 (p.Arg381Gln) variant against paediatric CD. IL23R was expressed in both CD and UC with a great variability. However, expression levels showed no significant association with the disease.

Betulinic acid treatment promotes apoptosis in hepatoblastoma cells.

Hepatoblastoma (HB) represents the most common malignant liver tumor in children with a dismal prognosis for patients with advanced disease. This study provides evidence that the naturally occurring pentacyclic triterpenoid betulinic acid (BA) is highly effective against HB. We demonstrate that BA has a strong cytotoxic effect on HB cells in a dose-dependent manner by impinging on cell viability and causing massive induction of programmed cell death. Apoptotic features including morphological changes, membrane asymmetry and proteolytic cleavage of caspase 3 and poly(ADP-ribose) polymerase were frequently found in BA-treated HB cells, which is suggestive of the mitochondrial intrinsic apoptotic pathway. In contrast, the hepatocellular carcinoma (HCC) cell line HepG2 was resistant to BA treatment. This insensitivity was dependent on the high expression of survival factors, such as Survivin and BCL2. Interestingly, BA treatment led to a significant decrease in expression of the hedgehog target genes GLI1, PTCH1 and IGF2 in HepT3 cells. In conclusion, we demonstrate that BA is capable of inducing apoptosis in HB cells and thereby might be a hopeful new strategy for treating HB, especially those with an activated hedgehog signaling pathway.

The relevance of surgical therapy for bilateral and/or multiple pulmonary metastases in children.

PURPOSE: Pulmonary surgery is frequently used for the treatment of metastases in children with various malignant diseases. The benefit of an aggressive surgical treatment in children with bilateral and/or multiple pulmonary metastases is still discussed controversially. METHODS: A retrospective analysis of 10 children (7 girls, 3 boys; age range from 2 to 16.5 years) who underwent thoracotomy for bilateral and/or multiple pulmonary metastases was performed. The primary malignancies were osteosarcoma (n = 4), hepatoblastoma (n = 3), malignant peripheral nerve sheath tumor (n = 1), adrenocortical carcinoma (n = 1) and alveolar rhabdomyosarcoma (n = 1). Unilateral but multiple pulmonary metastases were found in 3 children. 7 patients showed bilateral pulmonary metastases. Preoperative induction chemotherapy with tumor regression and a subsequent decrease in the size and number of pulmonary metastases was mandatory for the surgery of metastases. RESULTS: Standardized bilateral thoracotomy was performed in 4 patients in 1 operation (in 1 patient combined with a hemihepatectomy), and in 3 patients, in 2 operations on different days. 5 children underwent re-thoracotomy due to recurrent pulmonary metastases (2 patients: unilateral; 3 patients: bilateral; 1 patient: twice bilateral). All visible and palpable metastases (1 - 25) were excised, either by wedge resection, by segment resection or by lobectomy. Postoperative artificial ventilation was necessary for 0 to 24 hours. Postoperative complications included intrathoracic secondary hemorrhage in 3 cases and pneumonia in 1 patient. 2 patients (20%) died of recurrent metastatic disease (osteosarcoma: 1; adrenocortical carcinoma: 1). During a mean follow-up period of 49 months (14 to 66 months after the last thoracotomy), 8 patients (80%) remained in complete remission without clinically relevant respiratory restrictions. CONCLUSION: Complete surgical resection of pulmonary metastases after response to induction chemotherapy may increase survival in carefully selected children, even in cases with multiple and recurrent metastatic disease. In children, bilateral thoracotomy within a single operation is possible without an increased complication rate.

Tumor model for laparoscopy in pediatric oncology: subperitoneal inoculation of human hepatoblastoma cells in nude rats.

BACKGROUND: Minimally invasive surgery (MIS) for diagnostic or even ablative purposes in pediatric oncology is gradually evolving, but little is known about its biological consequences and surgical complications. Especially for hepatoblastoma (HB), no study on the influence of laparoscopy is available yet. A special tumor model could facilitate a variety of investigations. The present study introduces a laparoscopic technique to create subperitoneal metastases of human HB. METHODS: 7 immuno-incompetent (rnu/rnu) rats (mean weight 198 g) received a stab incision in the lower abdomen to insert a 4 mm scope. Under laparoscopic guidance (CO2 pressure of 1 mmHg, flow of 0.2 l/min) an 18 G needle was introduced, to inject several subperitoneal deposits of the tumor cell suspension (HuH6, 3 x 10 (6) in 1 ml of RPMI-1640 medium). Tumor growth was allowed for 6 - 7 weeks and finally the animals were laparoscopically evaluated for peritoneal metastases. Each suspicious lesion was harvested for histology. RESULTS: One animal was investigated after 6 weeks without evidence of tumor growth. After 7 weeks, in 4 out of 6 animals at least one lesion could be detected. Histology revealed HB in all specimens. CONCLUSION: Subperitoneal inoculation of human HB cells in nude rats achieves intraabdominal tumor growth. The present model allows a variety of laparoscopic strategies and their oncological impact to be studied. Thus it may contribute to the development of distinct oncological concepts for MIS in children with HB.