Intra-abdominal neuroectodermal tumour of childhood with divergent differentiation

Two cases are reported of intra-abdominal small cell tumours expressing concomitant neural and epithelial differentiation. These features were discernible on conventional microscopy and supported immunocytochemically. Immunoreactive vimentin was also revealed in both tumours, and, in addition, one showed focal desmin positivity. Epithelial differentiation in both tumours was confirmed ultrastructurally. The tumours were interpreted to represent a variant of peripheral primitive neuroectodermal tumour, and the report serves to emphasize a potential among such tumours for complex differentiation. The neoplasms are compared with other similar tumours reported recently in children.     

MDM2 and CDK4 gene amplification in Ewing's sarcoma

Amplification of the MDM2 gene, which maps to chromosome band 12q13 and encodes a p53-binding protein, may result in functional inactivation of p53 and has been observed in various bone and soft tissue sarcomas. Published studies have included few cases of Ewing's sarcoma (ES) or peripheral neuroectodermal tumour (PNET), a tumour group in which alterations of the p53 pathway have so far not been extensively studied. We examined two ES cell lines, RD-ES and SK-ES-1, and 30 specimens from 27 patients (24 ES, 6 PNET; 19 primary, 4 local recurrence, 7 metastasis) for MDM2 gene amplification by Southern blot analysis. All 30 clinical specimens had been confirmed to contain sufficient ES/PNET DNA by the demonstration of a rearrangement of the t(11;22)-associated EWS gene using an EWS cDNA probe on the same blots. MDM2 gene amplification was detected in 3 of 30 specimens (10 per cent), including two ES and one PNET, but in neither of the cell lines. The three cases with amplification were morphologically typical primary tumours. Two of the three cases also showed co-amplification of the CDK4 gene, which endoces a cyclin-dependent kinase and also maps to band 12q13. Clinically, all three cases had metastatic disease at diagnosis, compared with only 1 of 15 MDM2-negative cases where the primary tumour was studied. The difference was statistically significant (P=0.005), suggesting an association of MDM2 amplification with advanced stage. Further accural and multivariate analysis of ES/PNET cases with MDM2 gene amplification will be necessary to confirm the clinical significance of these findings. The results suggest that the prevalence of MDM2 gene amplification in ES/PNET is comparable to other sarcomas, and implicate dysfunction of the p53 pathway in a subset of ES/PNET. The biological significance of CDK4 co-amplification remains to be determined.     

Immunocytochemical study of 12E7 in small round-cell tumours of childhood: an assessment of its sensitivity and specificity

12E7 is a monoclonal antibody to the MIC2 gene product and can be applied to formalin-fixed, paraffin-embedded tissue. The diagnostic utility of 12E7 as a marker of Ewing's sarcoma and peripheral neuroectodermal tumour was assessed. Immunocytochemical studies were performed on 120 small round-cell tumours from children and adolescents. Immunoreactivity for 12E7 was seen in 13 of 15 Ewing's sarcomas, 14 of 15 peripheral neuroectodermal tumours, four of 14 embryonal rhabdomyosarcomas, seven of 11 T-lymphoblastic lymphomas and one T-cell acute lymphoblastic leukaemia. Immunoreactivity was located on the cell-membrane of Ewing's sarcomas, peripheral neuroectodermal tumours and lymphoid tumours while rhabdomyosarcomas showed weak, cytoplasmic staining in differentiated rhabdomyoblasts. Studies on alveolar rhabdomyosarcomas ( n = 10), acute myeloid leukaemias (3), B-lymphoblastic lymphomas (8), blastema-rich nephroblastomas (9), neuroblastomas (20) and retinoblastomas (10) as well as single examples of B-cell acute lymphoblastic leukaemia, Ki-1 anaplastic lymphoma of indeterminate phenotype and intra-abdominal desmoplastic tumour with divergent differentiation were negative. 12E7 is a sensitive marker for the Ewing's sarcoma/peripheral neuroectodermal group of tumours and is useful in distinguishing them from neuroblastoma and blastema-rich nephroblastoma. However, immunopositivity for 12E7 should be interpreted in conjunction with the results of neural and lymphoid markers.     

Primitive neuroectodermal (neuroepithelial) tumour of soft tissue of the neck in a child: demonstration of neuronal and neuroglial differentiation

A 4-year-old girl had a pathologically proven primitive neuroectodermal (neuroepithelial) tumour of soft tissue in the left posterolateral aspect of the neck. The neoplasm consisted of primitive neuroepithelial cells forming Homer Wright rosettes, mature ganglion cells and astrocytes. Astroglia were identified by localization of cytoplasmic glial fibrillary acidic protein (GFAP). Striking similarity is noted between the current tumour and those found in the central nervous system, including cerebellar medulloblastomas. The diverse cellular elements of the present primitive neuroectodermal neoplasm suggest an origin of the tumour from the neuroectodermal component of an ectomesenchymal remnant of the neural crest. Differentiation of the neuroectodermal component of the neural crest into primitive neuroepithelial cells could result in the occurrence of a primitive neuroectodermal neoplasm which may further differentiate into neurons and neuroglia.     

CHROMOSOMAL REARRANGEMENT t(11;22) IN EXTRASKELETAL EWING'S SARCOMA AND PRIMITIVE NEUROECTODERMAL TUMOUR ANALYSED BY FLUORESCENCE IN SITU HYBRIDIZATION USING PARAFFIN-EMBEDDED TISSUE

The clonal chromosomal rearrangement t(11;22) has been reported by karyotypic analysis to be specific for Ewing's sarcoma of bone and soft tissue origin as well as primitive neuroectodermal tumour. In this report, immunohistological analysis of MIC 2 expression and fluorescence in situ hybridization (FISH) were performed using paraffin-embedded tissues. We examined t(11;22) in the nuclei isolated from two Ewing's sarcomas, four primitive neuroectodermal tumours, and three neuroblastomas, which served as negative controls by FISH with an α-satellite DNA probe for chromosome 11, a chromosome 22 marker probe, and whole chromosome painting probes for both chromosomes 11 and 22. Both cases of Ewing's sarcoma and the four primitive neuroectodermal tumour specimens were immunoreactive for MIC 2. Both Ewing's sarcomas and three of the four primitive neuroectodermal tumours contained the tumour-specific t(11;22), but the three neuroblastomas did not show this translocation. Based on the cytogenetic results and on the immunohistological investigation of MIC 2 expression, Ewing's sarcoma is suggested to be related closely to primitive neuroectodermal tumour. FISH is a useful aid in determining the tumour type of Ewing's sarcoma and putative related tumours. © 1997 by John Wiley & Sons, Ltd.     

IL-6对大鼠急性髓系白血病R2细胞的增殖抑制及分化诱导作用

重组人白细胞介素６（ｒｈＩＬ－６）可抑制大鼠急性髓系白血病（ＡＭＬ）Ｒ２细胞的体外生长（ＩＣ５０１００ｎｇ／Ｌ），并在１０ｎｇ／Ｌ～１μｇ／Ｌ的剂量范围内诱导Ｒ２细胞向终末方向分化。诱导后的Ｒ２细胞具有单核巨噬细胞的形态特征；且非特异性酯酶（ＮＳＥ）及酸性醋酸酯酶（ＡＮＡＥ）的活性增强，而过氧化物酶（ＰＯＸ）的活性却一直很低。经典型的ＤＮＡ梯状条带及凋亡小体证实，≥１μｇ／ＬｒｈＩＬ－６亦可诱导Ｒ２细胞凋亡。我们认为，Ｒ２细胞是研究ＩＬ－６信号转导通路及ＡＭＬ细胞分化机制的一个很好模型。     

Divergent differentiation in small round-cell tumours of the soft tissues with neural features—an analysis of 10 cases

A series of 10 small round-cell tumours, having in common evidence of neural differentiation, were investigated by immunohistochemistry and electronmicroscopy. In seven, evidence of divergent muscle and/or epithelial differentiation was found. This phenomenon thus appears more common than previously appreciated and suggests that there may be a continuous and overlapping phenotypic spectrum from Ewing's tumour of soft tissue to intra-abdominal desmoplastic small cell tumour.     

Contribution of Electron Microscopy of Cell Cultures to the Classification of Three Round Cell Sarcomas in Children

We have studied three round cell sarcomas from pediatric patients in tissue culture to compare the electron microscopic morphology of cells in culture to cells from original biopsy specimens. None of the original tumors displayed distinctive features by light microscopy that would allow classification of a specific tumor type, and electron microscopy was not helpful in identifying specific morphologic features that would allow further classification of tumor types. However, electron microscopy of cells in culture from the three neoplasms revealed distinctive morphologic features that did allow further classification of all three tumors. Cells from an inguinal lymph node, which were cultured in soft agar tumor colony-forming assay, revealed Z-bands and actin and myosin filaments indicative of a rhabdomyosarcomatous nature for the tumor. Cells from 5-day, 10-day, and 4-month cultures of a bone marrow metastasis of a second tumor revealed features of skeletal muscle in the young cultures and neuroblasts in the older culture, suggesting a primitive neuroectodermal neoplasm. Cultured cells from the third tumor, a neoplasm of the calf in an infant, displayed large lakes of glycogen, typical of cells of Ewing's sarcoma, which were not present in the cells examined from the original lesion. Ultrastructural studies of cells in culture have the potential to add morphologic data that may be useful to further define and classify a neoplasm, as illustrated in the 3 cases reported here.     

Clinical and biological significance of hepatoma‐derived growth factor in Ewing's sarcoma

We sought to investigate the clinicopathological significance and biological function of hepatoma‐derived growth factor (HDGF) in Ewing's sarcoma. Our results showed that HDGF expression is up‐regulated in Ewing's sarcoma. Nuclear HDGF expression is significantly associated with tumour volume (p < 0.001), metastases at diagnosis (p < 0.001), low overall survival rate (p < 0.001) and low disease‐free survival rate (p < 0.001). HDGF knock‐down results in significant reduction of Ewing's sarcoma cell growth, proliferation and enhances tumourigenesis, both in vitro and in vivo. Meanwhile, HDGF knock‐down causes cell cycle arrest and enhanced sensitization to serum starvation‐induced apoptosis. Furthermore, recombinant HDGF promotes proliferation and colony formation of Ewing's sarcoma cells. Ninety‐eight candidate HDGF downstream genes were identified in Ewing's sarcoma cells using cDNA microarray analysis. In addition, we found that HDGF knock‐down inhibited FLI1 expression in Ewing's sarcoma cells at the mRNA and protein levels. Our findings suggest that HDGF exhibits oncogenic properties and may be a novel prognostic factor in Ewing's sarcoma. Targeting HDGF might be a potential therapeutic strategy for Ewing's sarcoma. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Heparin binding epidermal growth factor-like growth factor reduces ethanol-induced apoptosis and differentiation in human embryonic stem cells

Alcohol affects approximately 1% (40,000) of new born infants each year and is the main preventable cause of mental retardation in the US. Ethanol alters cell signaling and promotes apoptosis and differentiation. Heparin-binding epidermal growth factor-like growth factor (HB-EGF), a member of the EGF family of growth factors, has been reported to prevent apoptosis and differentiation. We treated human embryonic stem cells (hESCs) with ethanol (20 mM) to reflect casual drinking, with and without HB-EGF to measure its ability to prevent ethanol-induced apoptosis and differentiation. Apoptosis was measured by DNA fragmentation (terminal dUTP nick-end labeling assays) and activated caspase-3, while differentiation was accessed by SSEA-1 and OCT-3/4; western blotting assessed MAPK signaling. HB-EGF reduced SSEA-1 and elevated OCT-3/4, while reducing the amount of activated caspase-3 and DNA fragmentation. Western blot analysis showed HB-EGF prevents ethanol from altering MAPK phosphorylation. This data suggests that ethanol-induced apoptosis was reduced by HB-EGF, while hESC pluripotency was maintained.     

Bone morphogenetic protein is required for fibroblast growth factor 2-dependent later-stage osteoblastic differentiation in cranial suture cells

Background: Understanding the pathophysiological process of calvarial bones development is important for the treatments on relative diseases such as craniosynostosis. While, the role of fibroblast growth factor (FGF) and bone morphogenetic protein (BMP) and how they interacted in osteoblast differentiation remain unclear. Methods: we digested bone fragments around the coronal and sagittal sutures from newborn rats to harvest suture cells. Markers expression at different osteoblast differentiation stage was analyzed by increasing FGF2 concentration and BMP2 blocking in these cells. Results: BMP2 expression could be stimulated by FGF2 in a dose and time dependent manner. FGF2 stimulation may decrease early marker of osteoblast differentiation (collagen type-1, COL-1) and increase the expression of continuously-expressed or late markers (alkaline phosphatase, ALP; osteocalcin, OC and bone sialoprotein, BSP) to accelerate mineralization. Inhibition of BMP2 signaling by Noggin weakens the effect of FGF2 on induction of later-stage osteoblastic differentiation of cranial suture cells. Conclusion: Our data suggest that BMP2 signaling is required for FGF2-dependent induction of later-stage of cranial suture cell osteoblastic differentiation.     

Fibroblast growth factor 2 requires complex formation with ATP for neuroprotective activity

The neurotrophic and neuroprotective activity of fibroblast growth factor (FGF2) is well documented. In this study, we attempted to demonstrate that binding of ATP to FGF2 is essential for its neuroprotective effect. Incubation of primary cultures of rat embryonic (E18) cortical neurons with alkaline phosphatase decreased the ATP concentration in the culture medium from about 8 to 0.3 nM measured luminometrically. Reduction of ATP concentration below 1 nM abolished the neuroprotective effect of FGF2. However, when the more stable nucleotide triphosphate γS-ATP was used which could not be cleaved by alkaline phosphatase, FGF2 still protected the cultured cortical neurons against damage. In control experiments alkaline phosphatase alone did not influence neuroprotection. In addition, also ATPase and apyrase were used as ATP cleaving enzymes. Added to the culture medium, both enzymes were capable of decreasing ATP below the critical level of approximately 1 nM, and the neuroprotective activity of FGF2 was abolished. Thus, our results demonstrate for the first time that the FGF2/ATP complex but not FGF2 alone mediates neuroprotection.     

Peripheral primitive neuroectodermal tumour of the cervix

Peripheral primitive neuro-ectodermal tumours (PNET) of the cervix are very rare. Here, we report the clinical, pathological, immunohistochemical and genetic features of a case of a PNET located in the cervix. Hysterectomy revealed a cervical tumour. On microscopic examination, a vaguely lobular arrangement of uniformly appearing neoplastic cells, with round to oval nuclei, distinct nuclear membranes and a clear, moderately glycogen-rich cytoplasm was seen. Cells stained positive for LEU 7, S 100, monoclonal NSE and particularly for MIC2. Neurogenic differentiation was also seen by electron microscopic examination. The genetic hallmark of PNET, a 22q12 rearrangement was demonstrated by fluorescence in situ hybridisation experiments, supporting the diagnosis. Awareness of the existence of primary PNET of the cervix is important to avoid confusion with other tumours of the cervix. Received: 19 November 1998 / Accepted: 12 June 1999     

Peripheral primitive neuroectodermal tumour and extra-osseous Ewing's sarcoma; a histological,immunohistochemical and DNA flow cytometric study

Although peripheral primitive neuroectodermal tumour (pPNET) and extra-osseous Ewing's sarcoma (EES) are thought to be closely related neoplasms, their clinical behaviour differs considerably. To determine the clinical relevance of the Schmidt classification scheme for differentiating pPNET and EES, 20 tumour specimens of poorly differentiated round cell tumours were evaluated. In addition, the diagnostic value of several neural markers and the prognostic value of quantitative morphological variables (DNA ploidy, S-phase fraction, and the mitotic activity) were assessed. Homer-Wright rosettes were present in 9 tumours. Neuron specific enolase (NSE) was expressed in 11 tumours, 8 of which expressed a second neural marker (CD57, S100, or neurofilament). According to the Schmidt classification, 11 pPNET and 5 EES were distinguished. HBA-71 was exclusively expressed in pPNET and EES. The remaining tumours were classified as sarcoma not otherwise specified (n=2), rhabdomyosarcoma (n=1), and desmoplastic tumour with divergent differentiation (n=1). EES611 patients fared significantly better than the pPNET patients (100% versus 42% 5-year survival). Neither DNA ploidy nor S-phase fraction assessed in 12 evaluative histograms (9 pPNET and 3 EES), nor mitotic activity yielded information of additional prognostic value. On the basis of this study and the Schmidt classification scheme, it can be concluded that if the diagnosis of EES and pPNET is based on light microscopy (Homer-Wright rosettes) and/or immunohistochemistry (at least two neural markers, i.e. NSE, S-100, CD57, and neurofilament), the classification provides important clinical information. Furthermore, positivity for HBA-71 is helpful in differentiating pPNET and EES from all other small round cell tumours.     

Primitive neuroectodermal tumor of the myocardium: A case report, review of the literature, immunohistochemical, and ultrastructural study

We report the case of a primitive neuroectodermal tumor (PNET) arising in the heart of a 63-year-old man. The neuroectodermal nature of this tumor was confirmed by the immunohistochemical positivity for 013 (CD99) (the p30/32^MIC2 gene product) neuron specific enolase (monoclonal and polyclonal), synaptophysin and vimentin. Other markers, such as actin, desmin, myoglobin, chromogranin, keratin, and leukocyte common antigen were negative. The diagnosis was made on an endomyocardial biopsy and was confirmed in sections from the myocardial tumor found within the heart excised during cardiac transplant. Primitive neuroectodermal tumors have been reported in a variety of sites, most commonly in the extremities. No case has ever been reported within the myocardium, although one has been reported in the pericardium. In addition to morphological similarities, PNET and extraskeletal Ewing's sarcoma have been shown to possess the same chromosomal translocation, t11; 22, and the same cell surface antigen, P 30/32. Separation of this case from extraskeletal Ewing's sarcoma was possible because of the absence of PAS positivity, as well as the immunohistochemical positivity for at least two neural markers, as extraskeletal Ewing's sarcoma is only positive for neuron specific enolase.