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PubMed1997

Ventricular shunt infection and meningitis due to Bacillus cereus.

Non-anthrax Bacillus species are usually considered to be contaminants if found in clinical specimens. Only a few patients with systemic infections due to Bacillus cereus are reported. We present the case of a 18-month old boy with a primitive neuroectodermal tumor (PNET) in the brainstem and obstructive hydrocephalus that required an outlying and subsequently a ventriculoperitoneal drain. Following contamination at the site of entry of the external drain, shunt infection and meningitis with Bacillus cereus developed. Antibiotic treatment with vancomycin failed to eliminate the bacterium from the cerebrospinal fluid, so the shunt system had to be removed. Explantation of the shunt and addition of fosfomycin to the antibiotic regimen resulted in a complete cure of the infection.

Bacillaceae Infections↗
PubMed2003

Fatal pulmonary thromboembolism after a second course of high-dose chemotherapy with autologous peripheral blood stem cell transplantation.

We describe a 4-yr-old boy with an occult primitive neuroectodermal tumor, who suffered fatal PTE after a second course of HDC with autologous PBSCT. On day + 52 after a second PBSCT, he was admitted because of respiratory distress. Respiratory failure rapidly progressed and he died within 4 days. The diagnosis of PTE was confirmed by a lung perfusion study with technetium-99m macroaggregated albumin, but too late to allow treatment. Although rare, PTE must be recognized as an important differential diagnosis when respiratory symptoms are observed after HDC with PBSCT.

Antineoplastic Combined Chemotherapy Protocols↗
PubMedDate not supplied

Cardiorespiratory decompensation following methylprednisolone administration.

A 2-year-old white female receiving multidrug chemotherapy for treatment of a primitive neuroectodermal tumor developed acute hypotension, bradycardia, and shock following administration of ondansetron and high-dose methylprednisolone. The subsequent clinical course is described, and cardiovascular reactions to ondansetron and methylprednisolone are reviewed. While the etiology of this severe reaction is uncertain, it is possible that it represents an idiosyncratic reaction to the rapid administration of high-dose adrenal corticosteroids. Patients receiving high-dose corticosteroid therapy should be closely monitored, and slow rates of infusion are recommended.

Amoxicillin↗
PubMed1993

[Study on the mechanisms of thrombin to inhibit neurite outgrowth].

In the present study, we investigated the effects and signal transduction mechanisms of thrombin on neuronal differentiation of human primitive neuroectodermal tumor cell line CHP-100. Thrombin inhibited neurite outgrowth of CHP-100 cells in culture induced by serum removal. The inhibitory effects were found to be associated with activation of phosphatidylinositol turnover/calcium mobilization signal transduction pathway by thrombin, since stimulation with thrombin induced significant inositol-1, 4, 5 trisphosphate accumulation and intracellular free calcium transient in CHP-100 cells. In addition, the most potent inhibitor of thrombin hirudin, which reversed the inhibitory effect of thrombin on neurite outgrowth of CHP-100 cells, also inhibited thrombin-stimulated calcium transient. These results suggest a specific role of thrombin signal transduction pathway in the regulation of neuronal differentiation.

Brain Neoplasms↗
PubMed2005

Activation of c-Jun amino-terminal kinase by GDNF induces G2/M cell cycle delay linked with actin reorganization.

It is well known that the cell cycle is controlled by several cyclin/cyclin-dependent kinase (Cdk) complexes whose expression and phosphorylation states vary with orderly periodicity. During the cell cycle, activity of the cyclin/Cdk complexes can be regulated directly or indirectly by a number of molecules, including protein kinases and phosphatases, p53, and Cdk inhibitors. Here, we show that the addition of glial cell line-derived neurotrophic factor (GDNF) induced G2/M cell cycle delay in human SK-N-MC neuroectodermal tumor cells that express RET tyrosine kinase, accompanying actin reorganization. Cell cycle delay at G2/M was characterized by accelerated and prolonged Cdc2 phosphorylation and stabilization of cyclin B1 and Wee1 kinase expression. Interestingly, we found that phosphorylation and/or expression of Cdc2, cyclinB1, and Wee1 was controlled by the Rac1/c-Jun NH2-terminal kinase (JNK) pathway. Immunohistochemical analysis suggested that the G2/M cell cycle delay may be necessary to prevent the mitotic progression of SK-N-MC cells with perturbed actin cytoskeletons.

Actins↗
PubMed1996

Association of a suprasellar mass and intraocular retinoblastoma: a variant of pineal trilateral retinoblastoma?

OBJECTIVE AND IMPORTANCE: 'Trilateral retinoblastoma' designates the association of bilateral retinoblastomas with an ectopic (non-metastatic) intracranial primitive neuroectodermal tumor (PNET). Although the intracranial tumor, usually located in the pineal region, is seen 2-3 years after discovery of the bilateral ocular tumors, variant presentations do occur. The intraocular tumor can be unilateral, and the intracranial tumor can be suprasellar, presenting before the retinal lesions. CLINICAL PRESENTATION: A 4-month-old boy presented with irritability, vomiting and nystagmus. Head CT revealed a large calcified sellar-suprasellar mass. Ocular examination disclosed white macular lesions in the right fundus. He was taken to surgery where subtotal resection of the sellar-suprasellar mass was achieved. Microscopic examination showed a primitive, small, round, blue cell tumor consistent with retinoblastoma. The right ocular lesions, also consistent with retinoblastoma, were treated by cryosurgery. CONCLUSION: The appearance of a suprasellar PNET can precede the appearance of retinal masses in retinoblastoma. The literature suggests that patients with 'sellar' trilateral retinoblastoma have characteristics that differ from patients with a pineal region trilateral retinoblastoma: the intracranial mass more often presents initially; it occurs at a younger age; it is predominant in females, and is more often associated with unilateral ocular lesions. Retinal screening of patients with suprasellar PNET and other atypically located PNETs may disclose more cases of sellar 'trilateral retinoblastoma' and hereditary retinoblastomas. This will have implications on genetic counseling as siblings harboring the disease may be diagnosed and treated at an earlier stage.

Brain Neoplasms↗
PubMed2000

Expression of the neurotrophin receptor p75NTR in medulloblastomas is correlated with distinct histological and clinical features: evidence for a medulloblastoma subtype derived from the external granule cell layer.

Medulloblastomas (MBs) are primitive neuroectodermal tumors (PNET) of the cerebellum. They represent the most frequent malignant pediatric brain tumors, but their origin still remains unresolved and controversial. MB cells correspond to different stages of neural development and differentiation as illustrated by their expression of neuronal and glial markers. In the present study, we examined the expression pattern of the common low-affinity neurotrophin receptor p75NTR in a series of 167 MBs by immunohistochemistry. While p75NTR was present in only 17% of classic MBs (CMB), we found expression of p75NTR in all desmoplastic (nodular) MBs (DMB) examined, and in 71% of those MBs with a significant desmoplastic component. Furthermore, both desmoplastic histology and p75NTR expression were present preferentially in those tumors of adolescents and adults that are frequently located laterally in the cerebellar hemispheres. In DMBs, p75NTR was expressed predominantly in the proliferative, reticulin-rich areas, which may show coexpression of GFAP. In the pale islands of DMB, p75NTR was expressed only weakly or was absent. The expression pattern showed an inverse relation to that of the synaptic vesicle protein synaptophysin that was predominant in p75NTR negative classic MBs. Since the neurotrophin receptor p75NTR is expressed in cells of the external granule cell layer (EGL) of the fetal cerebellum, our findings suggest that progenitor cells of the EGL are the cellular origin of a distinct subset of MB, namely the desmoplastic variant and MBs with a significant desmoplastic component.

Adult↗
PubMedDate not supplied

Long-term follow-up and prognostic factors in Ewing's sarcoma. A multivariate analysis of 116 patients from a single institution.

The records of 116 patients from a single center (1970-1993) with newly diagnosed Ewing's sarcoma or primitive neuroectodermal tumor were reviewed retrospectively. The aim of this study was to ascertain the impact of pretreatment variables on disease-free survival. Median age was 14 years (range 1-34). Twenty patients presented with metastatic disease. Treatment consisted of systemic multiagent chemotherapy plus local irradiation (39%), wide resection (22%), or both (35%). Median potential follow-up was 10.7 years (range 2-26). Three patients developed second malignancies (1 breast carcinoma, 2 acute myeloid leukemias). Median time to relapse was 24 months (range 3-143). The actuarial disease-free survival was 37.4% at 5 years, 33.3% at 10 years and 27.8% at 15 years. Neoadjuvant chemotherapy and a therapy-induced tumor necrosis > or = 90% were associated with a better outcome. Patients undergoing surgical resection had a superior disease-free survival than those treated without surgery (45 vs. 18% at 10 years, p = 0.0009). Multiple regression analysis showed that raised serum lactate dehydrogenase levels (p < 0.001), hypoalbuminemia (p = 0.001) and distant metastases at diagnosis (p = 0.03) were independent adverse prognostic factors. In conclusion, one third of patients with Ewing's sarcoma become long-term survivors with combined modality treatment. Late relapses and second neoplasms are of concern. Prognostic factors should be considered in the selection of therapy, and the value of serum albumin warrants confirmatory studies.

Actuarial Analysis↗
PubMed1994

Cloning of the entire FLI1 gene, disrupted by the Ewing's sarcoma translocation breakpoint on 11q24, in a yeast artificial chromosome.

FLI1 (Friend leukemia virus integration 1), a member of the Ets gene family, is disrupted on 11q24 by the Ewing's Sarcoma (ES) and Peripheral Neuroepithelioma (PNE) t(11;22)(q24;q12) translocation. ES and PNE are Primitive Neuroectodermal Tumors (PNETs) and the consistent translocation t(11;22)(q24;q12) can be used for differential diagnosis. In PNETs the 3' part of human FLI1 is translocated from 11q24 to 22q12, where it is juxtaposed to the 5' end of the Ewing's Sarcoma gene (EWS). A fusion transcript, resulting in a chimeric protein, is generated. Here, we present the isolation and detailed characterization of a 250-kb colinear YAC, B45C11, which encompasses the ES and PNE breakpoint on 11q24, as shown by FISSH on ES and PNE chromosomes and interphase nuclei. This YAC represents a new reagent for potential use in rapid differential diagnosis by FISSH on tumor biopsies and on paraffin embedded samples, particularly when DNA and/or RNA are not available for molecular analysis. YAC B45C11, which spans 250 kb of contiguous DNA around the ES and PNE breakpoint, contains the entire FLI1 gene. Three potential HpaII-tiny-fragment (HTF) islands are revealed within the YAC. One of these islands appears to be associated with the 5' end of FLI1, which extends over approximately 120 kb of DNA on 11q24. In addition, we demonstrate that YAC B45C11 contains other transcribed sequences in addition to FLI1, by "cross-species" Northern blot hybridizations, which suggests the presence of additional genes in the immediate vicinity of the ES breakpoint on 11q24.

Base Sequence↗
PubMed1998

Evidence that TSG101 aberrant transcripts are PCR artifacts.

Critical analysis of the data published so far concerning the TSG101 gene revealed some inconsistencies leading us to its re-evaluation in 80 breast, brain, colon, and neuroectodermal tumors and 37 normal tissue specimens. In this study, the occurrence of TSG101 cDNA aberrant transcripts was verified, but in addition we made observations that are in apparent conflict with the aberrant splicing theory supposed as the underlying mechanism for transcript formation: the location of most deletion breakpoints within exons and nonconformity of these putative splice sites with the highly conserved GT-AG rule, detection of insertions as well as nonreproducible and highly variable results in repeated RT-nested PCRs. Furthermore, we found that reamplification of full-length TSG101 cDNA products leads to the generation of deleted transcripts. In summary, for the first time we provide evidence that the acquired TSG101 transcripts are caused by PCR artifacts.

Artifacts↗
PubMed1996

Expression of memory, differentiation, and repression of c-myc and p53 genes in human RD/TE-671 cells induced by a ureido-derivative of pyridine (UDP-4).

Human TE-671 cells have been used to study several aspects of neuroectodermal tumors in culture. Since the human TE-671 cell lines has been re-identified as a rhabdomyosarcoma (RD) rather than a medulloblastoma due to the presence of muscle-type nicotinic acetylcholine receptors, we re-investigated the nature of RD/TE-671 cells and characterized their differentiation induced by 2-(3-ethylureido)-6-methylpyridine (UDP-4), a potent inducer of differentiation of neoplastic cells. RD cells were also used for comparative studies. RD/TE-671 cells exposed to UDP-4 were differentiated irreversibly into postmitotic cells expressing mainly neurofilaments and, to a lesser extent, myoid proteins. In contrast to RD cells that expressed preferentially myoid and not neurofilament proteins (NFPs) upon treatment with UDP-4, differentiated RD/TE-671 cells exhibited characteristic dendritic processes and expressed NFPs (NFP68, NFP160, and NFP200), parvalbumin (calcium-binding protein), and neuron-specific enolase, as well as a small amount of vimentin and desmin. In addition, differentiated RD/TE-671 cells expressed memory for differentiation and underwent an irreversible limitation of proliferation, loss of clonogenic potential, selective repression of c-myc and p53 proto-oncogenes, and changes in cell surface architecture. Treatment of RD/ TE-671 cells with nerve growth factor or epidermal growth factor in the presence of UDP-4 did not alter the phenotype of differentiated cells, whereas co-treatment with 12-O-tetradecanoylphorbol-13-acetate and UDP-4 enhanced morphological differentiation. Therefore, we conclude that: (a) RD/TE-671 cells challenged with UDP-4 express memory to differentiate in the absence of inducer; (b) in contrast to RD cells, RD/TE-671 cells appear to be multipotent cells of neuroectodermal origin capable of differentiation into cells expressing neuronal rather than myoid proteins upon treatment with UDP-4; and (c) differentiation of RD/TE-671 cells leads to selective cessation of cell proliferation and repression of c-myc and p53 proto-oncogenes.

Cell Differentiation↗
PubMed1998

Treatment of children with relapsed soft tissue sarcoma: report of the German CESS/CWS REZ 91 trial.

BACKGROUND: The present study was performed to evaluate the possibilities of relapse treatment in patients heavily pretreated for a soft tissue sarcoma. PATIENTS AND METHODS: Prospective, multicenter study in 44 soft tissue sarcoma (STS) patients with first relapse. Primary diagnosis was embryonal rhabdomyosarcoma (RME) in 17 patients, alveolar rhabdomyosarcoma (RMA) in 13, primitive neuroectodermal tumor (PNET) in 6, and miscellaneous soft tissue sarcomas in 8 patients. Initial chemotherapy consisted of carboplatin/etoposide combination (150 mg/m2 each, days 1 to 4) followed by local therapy including surgical treatment and, whenever possible, radiotherapy. RESULTS: In 11/17 patients without primary tumor resection, CR or PR was achieved following the initial two cycles of chemotherapy (61%). The probability of event-free survival (pEFS) for RME patients was 0.41 +/- 0.12 at 5 years, and 0.25 +/- 0.12 for RMA patients. But, in contrast no PNET patient or patient with another soft-tissue sarcoma achieved long-term remission. Additional local radiotherapy significantly (P = 0.002) improved pEFS (3-year estimates of 0.23 +/- 0.2 vs. 0.1 +/- 0.1 in patients without radiotherapy). CONCLUSIONS: In patients with RME, relapse treatment employing a carboplatin/etoposide combination may induce a second remission in approximately 40% of patients. Surgical excision and additional local radiotherapy seem to be essential to maintain a stable remission. In patients with RMA or PNET, however, this treatment strategy is of no long-term benefit.

Antineoplastic Agents, Alkylating↗
PubMedDate not supplied

Signal transduction pathway to low-dose radiation-induced apoptosis in peripheral PNET cells.

We investigated the signal transduction pathway to low-dose radiation-induced apoptosis in vitro in the human peripheral primitive neuroectodermal tumor (pPNET) cell line with wild-type p53 established in our laboratory. Apoptosis was induced by 2Gy irradiation in an almost p53-dependent manner in this model except for a deficiency of the cleavage of caspase-9. It was detected 3 hours after irradiation by fragmentation assay. The expressions of p53, p21WAF-1 and Bax increased, in contrast to the gradually decreasing expression of Bcl-2, as observed by immunoblotting. Following this, cleavages of caspase-3 and PARP reached peak levels. There were no detectable increases in ERK expression and caspase-9 cleavage. In respect of the probability of other pathways to apoptosis, this cell line will provide a useful model both for investigating low-dose radiation-induced signal transduction pathway and for analyzing the biological characteristics of pPNET.

Adult↗
PubMed1996

Regulation by retinoic acid of insulin-degrading enzyme and of a related endoprotease in human neuroblastoma cell lines.

Physiologically, the action of insulin-like growth factors (IGFs) is controlled at different levels, from its transcription start by tissue-specific and development-specific transcriptional factors to its degradation by peptidases such as insulin-degrading enzyme (IDE). Since IGF-II is the major autocrine/paracrine growth factor for neuroblastoma cells, we studied the expression and the role of IDE in this system. Here, we show that (a) IDE is expressed in several human neuroectodermal tumor cell lines, including neuroblastoma cell lines; (b) in a neuroblastoma cell line, IDE expression is up-regulated by retinoic acid, a well-known inducer of neuronal differentiation and/or programmed cell death; (c) IDE is probably not the only IGF-degrading enzyme present in these cells, since the activity of a novel thermolysin-like metalloendopeptidase, clearly distinct from IDE, is also detected. The TME activity is inhibited by IGF-I, Des-IGF-I, and IGF-II, and it is down-regulated by retinoic acid. Since retinoic acid plays a relevant role in controlling the growth of these cells and affects the expression of IDE, we have also: (a) identified the retinoic acid receptors (RARs) and retinoid X receptors (RXRs) expressed in these cell lines and (b) by means of synthetic retinoid analogues identified the RAR/RXR isoforms whose activation may be sufficient to induce the expression of the IDE gene. These results provide evidence that complex posttranslational molecular mechanisms participate in the autocrine/paracrine growth control of the IGF-II loop in neuroblastomas involving proteolytic systems.

Endopeptidases↗
PubMed2003

Parental occupational exposure to pesticides and childhood brain cancer.

The authors examined the risk of childhood brain cancer in relation to parental exposure to classes of pesticides among 154 children diagnosed with astrocytoma and 158 children diagnosed with primitive neuroectodermal tumors (PNET) in the United States and Canada between 1986 and 1989. Controls were selected by random digit dialing and were individually matched to cases by race, age, and geographic area. Each job in the fathers' work history and the usual occupation of mothers were assigned a probability, intensity, and frequency of exposure to insecticides, herbicides, and agricultural and nonagricultural fungicides. Elevated risks of astrocytoma were found for paternal exposure (ever vs. never) to all four classes of pesticides (odds ratio (OR) = 1.4-1.6). An increased risk of PNET was observed for only herbicides (OR = 1.5). For mothers, odds ratios for astrocytoma were elevated for insecticides, herbicides, and nonagricultural fungicides (OR = 1.3-1.6) but not agricultural fungicides (OR = 1.0). No indication was found of an increased risk for PNET. There was little indication for an association with cumulative and average parental exposure. Most risk estimates were around unity, and exposure-response patterns were absent. Overall, it seems unlikely that parental exposure to pesticides plays an important role in the etiology of childhood brain cancer.

Adult↗
PubMed2000

Cytokeratin immunoreactivity in Ewing's sarcoma: prevalence in 50 cases confirmed by molecular diagnostic studies.

Ewing's sarcoma (ES) and primitive neuroectodermal tumor (PNET) are characterized by the presence of the specific t(11;22)(q24;q12) or variants thereof, producing diagnostic EWS fusion transcripts. Cytokeratin has been reported sporadically to be expressed in some cases of ES/PNET. However, its prevalence has not been assessed systematically in a series of cases with confirmatory molecular or cytogenetic evidence of a diagnostic translocation. We present in detail three index patients in whom strong cytokeratin immunoreactivity was a confounding factor in the diagnosis. To establish further the prevalence of cytokeratin immunoreactivity in a series of well-characterized ES/PNET, we then performed immunohistochemical studies with antibodies CAM5.2 and AE1/AE3 on 50 cases of ES/PNET diagnosed at Memorial Sloan-Kettering Cancer Center in which molecular evidence of a specific ES/PNET-associated translocation were available. Immunoreactivity to cytokeratin was present in 10 cases (20%), in five diffusely and five focally. There was no significant association between cytokeratin expression and the following parameters: patient age, sex, skeletal and extraskeletal primary site, and the type of EWS fusion transcript. Cytokeratin expression, a manifestation of epithelial differentiation, is present in as many as 20% of ES/PNET in either a diffuse or focal pattern.

Adult↗
PubMed2004

Intensity-modulated radiotherapy in treatment of pancreatic and bile duct malignancies: toxicity and clinical outcome.

PURPOSE: To assess the efficacy and toxicity of intensity-modulated radiotherapy (IMRT) in pancreatic and bile duct (cholangiocarcinoma) malignancies. METHODS AND MATERIALS: Twenty-five patients with pancreatic and bile duct cancer were treated with IMRT. Twenty-three received concurrent 5-fluoruracil. One patient with a pancreatic primitive neuroectodermal tumor received concurrent etoposide and ifosfamide. Eight patients had resected tumors, and 17 had unresectable primary (n = 14) or recurrent (n = 3) tumors. Six patients underwent treatment planning with conventional three-dimensional four-field techniques for dosimetric comparison with IMRT. RESULTS: Compared with conventional RT, IMRT reduced the mean dose to the liver, kidneys, stomach, and small bowel. IMRT was well tolerated, with 80% experiencing Grade 2 or less acute upper GI toxicity. At a median follow-up of 10.2 months, no resected patients had local failure, and only 1 of 10 assessable patients with unresectable cancer had local progression. The median survival and distant metastasis-free survival of the 24 patients with adenocarcinoma was 13.4 and 7.3 months, respectively. Grade 4 late liver toxicity occurred in 1 patient surviving >5 years. The remainder of the assessable patients experienced no (n = 9) or Grade 1 (n = 4) late toxicity. CONCLUSION: In this hypothesis-generating analysis, the acute and chronic toxicity profile with IMRT in the treatment of pancreatic and bile duct cancer was encouraging. Local control was not compromised, despite efforts to increase conformality and avoid doses to normal structures. Distant failure remains a major obstacle in pancreatic cancer.

Adenocarcinoma↗
PubMed2005

Molecular cytogenetic characterization of an ins(4;X) occurring as the sole abnormality in an aggressive, poorly differentiated soft tissue sarcoma.

Cytogenetic and fluorescence in situ hybridization (FISH) analysis of an aggressive undifferentiated soft tissue sarcoma diagnosed as primitive neuroectodermal tumor (PNET) revealed an insertion ins(4;X)(q31-32;p11p22) as the sole aberration. To identify the molecular genetic consequences, contigs of bacterial artificial chromosomes (BACs) covering Xp11-p22 and 4q31-32 were constructed. The breakpoint in Xp22 was considered unlikely to be of pathogenetic significance, as it was very close to the Xp telomere, a region devoid of known or predicted genes. The breakpoint in Xp11 was mapped within a BAC clone containing BCOR, encoding a BCL6 (B-cell lymphoma 6)-interacting protein that may influence apoptosis, as the only known gene. FISH analysis with three overlapping clones on normal chromosomes 4 disclosed that the insertion of Xp11 material in der(4) was accompanied by a deletion of chromosome 4 material. Only a predicted gene (XM_094074) was shown to be partially included in the deletion. This gene displays a high similarity with the gene encoding the embryonic blastocoelar extracellular matrix (ECM) protein in sea urchin, which is involved in the migration of the primary mesenchyme cells during embryogenesis. Our results suggest that BCOR and/or an ECM-like protein could be involved in the pathogenesis of a subgroup of PNET or PNET-like sarcomas.

Adolescent↗