1: Cancer Genet Cytogenet. 2005 Jun;159(2):123-8. Cytogenetic aberrations in spontaneous endometrial adenocarcinomas in the BDII rat model as revealed by chromosome banding and comparative genome hybridization. Hamta A, Adamovic T, Heloua K, Levan G. CMB-Genetics, Lundberg Laboratory, Goteborg University, Box 462, SE 40530, Gothenburg, Sweden. Female rats of the inbred strain BDII are genetically predisposed to endometrial estrogen-dependent adenocarcinomas (EAC). More than 90% of them spontaneously develop this tumor type before the age of 24 months. In order to dissect out the genetic components behind these tumors we have made crosses between BDII females and rats from 2 other strains that are nonsusceptible to EAC. It was found that EAC tumors developed in a subset of intercross and backcross animals from both interstrain crosses. The chromosomal changes in the developing tumors were studied using cytogenetic and molecular cytogenetic methods. From these studies, we conclude that certain chromosome regions were recurrently engaged in chromosomal changes such as increases in copy number (e.g., trisomy, amplification) or decreases (e.g., deletion). Based on the analysis of 56 tumors, 8 regions were found to be particularly often involved: RNO4prx, gain=34 (61%) (amplification 12 cases); RNO5mid, loss=15 (27%); RNO6prx, gain=25 (45%) (amplification 8 cases); RNO10 loss, prx-mid/gain dst=25 (45%) (amplification 1 case); RNO12q, gain=23 (41%); RNO15p loss/RNO15q gain=29 (52%) (amplification 1 case) [RNO, rat chromosome; prx, proximal; mid, middle; dst, distal; p, short arm; q, long arm]. We begun to analyze these regions in detail using various molecular methods and within them there are certain possible target genes, such as MET (RNO4q21), CDKN2A/2B (RNO5q32), MYCN (RNO6q15 approximately q16), and TP53 (RNO10q24 approximately q25), but it is clear that several other genes, still unidentified, must also be involved. PMID: 15899383 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 2: Mol Cell Biol. 2005 Mar;25(6):2395-405. The novel ETS factor TEL2 cooperates with Myc in B lymphomagenesis. Cardone M, Kandilci A, Carella C, Nilsson JA, Brennan JA, Sirma S, Ozbek U, Boyd K, Cleveland JL, Grosveld GC. Department of Genetics, St. Jude Children's Research Hospital, 332 North Lauderdale, Memphis, TN 38105, USA. The human ETS family gene TEL2/ETV7 is highly homologous to TEL1/ETV6, a frequent target of chromosome translocations in human leukemia and specific solid tumors. Here we report that TEL2 augments the proliferation and survival of normal mouse B cells and dramatically accelerates lymphoma development in Emu-Myc transgenic mice. Nonetheless, inactivation of the p53 pathway was a hallmark of all TEL2/Emu-Myc lymphomas, indicating that TEL2 expression alone is insufficient to bypass this apoptotic checkpoint. Although TEL2 is infrequently up-regulated in human sporadic Burkitt's lymphoma, analysis of pediatric B-cell acute lymphocytic leukemia (B-ALL) samples showed increased coexpression of TEL2 and MYC and/or MYCN in over one-third of B-ALL patients. Therefore, TEL2 and MYC also appear to cooperate in provoking a cadre of human B-cell malignancies. PMID: 15743832 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 3: Proc Natl Acad Sci U S A. 2005 Jan 18;102(3):731-6. Epub 2005 Jan 11. The p53 regulatory gene MDM2 is a direct transcriptional target of MYCN in neuroblastoma. Slack A, Chen Z, Tonelli R, Pule M, Hunt L, Pession A, Shohet JM. Center for Cell and Gene Therapy, Texas Children's Cancer Center, Baylor College of Medicine, 1102 Bates Street, Houston, TX 77030, USA. The MYCN oncogene is the major negative prognostic marker in neuroblastoma with important roles in both the pathogenesis and clinical behavior of this aggressive malignancy. MYC oncogenes activate both proliferative and apoptotic cellular pathways and, accordingly, inhibition of p53-mediated apoptosis is a prerequisite for MYC-driven tumorigenesis. To identify novel transcriptional targets mediating the MYCN-dependent phenotype, we screened a MYCN-amplified neuroblastoma cell line by using chromatin immunoprecipitation (ChIP) cloning. We identified the essential p53 inhibitor and protooncogene MDM2 as a putative target. MDM2 has multiple p53-independent functions modulating cell cycle and transcriptional events. Standard ChIP with MYCN antibodies established the binding of MYCN to a consensus E-box within the human MDM2 promoter. Oligonucleotide pull-down assays further established the capacity of MYCN to bind to this promoter region, confirming the ChIP results. Luciferase reporter assays confirmed the E-box-specific, MYCN-dependent regulation of the MDM2 promoter in MYCN-inducible neuroblastoma cell lines. Real-time quantitative PCR and Western blot analysis demonstrated a rapid increase in endogenous MDM2 mRNA and MDM2 protein upon induction of MYCN. Targeted inhibition of MYCN in a MYCN-amplified neuroblastoma cell line resulted in decreased MDM2 expression levels with concomitant stabilization of p53 and induction of apoptosis. Our finding that MYCN directly modulates baseline MDM2 levels suggests a mechanism contributing to the pathogenesis of neuroblastoma and other MYC-driven malignancies through inhibition of MYC-stimulated apoptosis. PMID: 15644444 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 4: Anticancer Res. 2004 Mar-Apr;24(2B):987-98. Curcumin and resveratrol induce apoptosis and nuclear translocation and activation of p53 in human neuroblastoma. Liontas A, Yeger H. Department of Paediatric Laboratory Medicine, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada. BACKGROUND: Neuroblastoma (NB) is an aggressive childhood cancer of the peripheral nervous system arising from neural crest sympathoadrenal progenitor cells. Despite current rigorous treatment protocols, prognosis for high stage NB patients is poor and so there remains a need for more effective, less cytotoxic treatments. Curcumin and resveratrol possess anti-tumor properties in adult cancer models and negligible toxicity in normal cells, but little is known about the effect of these agents on pediatric cancers. MATERIALS AND METHODS: Stage 4 MYCN-amplified NB cell lines, with wild-type or mutant p53, were treated with curcumin and resveratrol and analyzed for effects on proliferation, cell cycle, induction of apoptosis and p53 function. RESULTS: Treatment induced a dose- and time-dependent decrease in cell viability, cell cycle arrest and induction of apoptosis. Treatment transiently up-regulated p53 expression and induced nuclear translocation of p53, followed by induction of p21(WAF-1/CIP-1) and Bax expression. CONCLUSION: Observations suggest that the cytotoxicity, cell cycle arrest and apoptosis induced by curcumin and resveratrol in NB cells may be mediated via functionally activated p53 and merit further study. PMID: 15161054 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 5: Cancer Genet Cytogenet. 2004 Mar;149(2):154-60. Molecular cytogenetic parameters in fibroblasts from patients and carriers of xeroderma pigmentosum. Amiel A, Peretz G, Slor H, Weinstein G, Fejgin MD. Sackler School of Medicine, Tel-Aviv University, Ramat Aviv 69978, Israel. Amiel.Aliza@clalit.org.il Xeroderma pigmentosum (XP) is a rare autosomal recessive syndrome. Laboratory investigations have failed to detect any consistent anomaly in cells from XP heterozygotic subjects, although examples of behavior intermediate between normal and XP cells have been reported. To estimate random aneuploidy we applied fluorescence in situ hybridization (FISH) with alpha-satellite probes for chromosomes 8 and 9 and replication pattern for TP53 (p53), ERBB2 (HER-2/neu), and MYCN (N-MYC) loci and for the imprinted SNRPN locus. A significantly higher rate of aneuploidy rate was observed in XP patients and carriers than in controls. The asynchrony pattern was significantly higher in XP carriers and patients with all three coding loci analyzed and significantly lower in XP patients and carriers with the imprinted locus SNRPN than in the control group. Molecular cytogenetic parameters such as random aneuploidy and replication pattern, which are known to reflect chromosomal instability, may be part of the tumorigenesis process. In XP patients and carriers, this genetic instability may represent a potential for developing malignancies. PMID: 15036891 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 6: Prog Brain Res. 2004;146:233-42. Neural crest development and neuroblastoma: the genetic and biological link. Nakagawara A. Division of Biochemistry, Chiba Cancer Center Research Institute, 666-2 Nitona, Chuoh-ku, Chiba 260-8717, Japan. akiranak@chiba-ccri.chuo.chiba.jp Neuroblastoma is one of the most common pediatric solid tumors originating from the sympathoadrenal lineage of neural crest. The tumor shows extremely different clinical phenotypes such as spontaneous regression on one hand and aggressive growth on the other hand. The different biological behavior of neuroblastoma appears to be determined by the genetic abnormalities including amplification of MYCN oncogene, DNA ploidy and some allelic imbalances. However, the spontaneous regression of neuroblastoma mimics the programmed cell death normally occurring in developing sympathetic cells expressing both TrkA tyrosine kinase A and p75NTR neurotrophin receptor. Indeed, TrkA expression is the most important factor related to the induction of tumor cell differentiation and/or programmed cell death because without its expression spontaneous regression of neuroblastoma never occurs. Thus, the enigmatic clinical behaviors of neuroblastoma are strictly linked to the molecular mechanism of neural crest development. PMID: 14699967 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 7: Mod Pathol. 2003 Dec;16(12):1248-56. Detection of single-copy chromosome 17q gain in human neuroblastomas using real-time quantitative polymerase chain reaction. Morowitz M, Shusterman S, Mosse Y, Hii G, Winter CL, Khazi D, Wang Q, King R, Maris JM. Division of Oncology, Children's Hospital of Philadelphia, Pennsylvania 19104-4318, USA. Regional genomic alterations resulting from single-copy allelic loss or gain have been well characterized in many human cancers and are often of prognostic relevance. Unbalanced gain of 17q material is common in malignant human neuroblastomas and typically results from unbalanced translocations. Unbalanced 17q gain may be an independent predictor of disease outcome, but technical difficulties with quantifying such gain using fluorescent in situ hybridization gives this method limited clinical applicability. We now describe a duplex genomic DNA-based quantitative polymerase chain reaction assay to determine the presence or absence of unbalanced gain of chromosome 17q in primary neuroblastoma specimens. The technique was first refined and validated in a panel of nine human neuroblastoma-derived cell lines by direct comparison with dual-color fluorescent in situ hybridization. Prospective blinded comparison of quantitative polymerase chain reaction and fluorescence in situ hybridization in 40 human neuroblastoma primary tumor samples showed a sensitivity of 96% and 100% specificity for detecting unbalanced 17q gain when a relative 17q copy number ratio of 1.3 was used to define unbalanced gain. Tumors with ratios >1.3 were highly associated with malignant tumor phenotypic features such as metastatic disease (P <.0001) and tumor MYCN amplification (P =.008). These data suggest that quantitative polymerase chain reaction determination of 17q status is feasible and highly specific in primary tumor samples. Sensitivity may be limited because of the inherent complexity of both the chromosomal rearrangements and heterogeneity of some tumor samples. Taken together, quantitative polymerase chain reaction can be used as a high-throughput screening tool for 17q aberrations, but a subset of samples may also require fluorescence in situ hybridization analysis in an attempt to conclusively determine 17q allelic status. PMID: 14681326 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 8: Cancer Lett. 2003 Jul 18;197(1-2):93-8. The p53 pathway and its inactivation in neuroblastoma. Tweddle DA, Pearson AD, Haber M, Norris MD, Xue C, Flemming C, Lunec J. Cancer Research Unit, The Medical School, University of Newcastle, Newcastle-upon-Tyne NE2 4HH, UK. d.a.tweddle@newcastle.ac.uk Early studies of p53 in neuroblastoma reported infrequent mutations in tumours and cell lines. Cytoplasmic sequestration was later proposed as an alternative mechanism of inactivation, but many studies have since reported an intact p53 pathway in neuroblastoma cell lines, as detected by nuclear p53 accumulation after DNA damage, intact DNA binding, transcriptional activation of target genes and the induction of apoptosis. In some MYCN amplified cell lines however, an irradiation induced G(1) arrest does not occur, despite the presence of normal p53. Neuroblastoma usually responds to chemotherapy but frequently relapses, and there is evidence from tumours, and cell lines that p53 inactivation via mutation or MDM2 amplification occurs at relapse and is sometimes associated with multidrug resistance. If p53 inactivation occurs frequently in relapsed tumours it may be appropriate to include p53 independent therapies in the initial management of high-risk neuroblastoma. Publication Types: Review Review, Tutorial PMID: 12880966 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 9: Eur J Cancer. 2003 Jul;39(10):1478-85. Aberrant methylation of multiple genes in neuroblastic tumours. relationship with MYCN amplification and allelic status at 1p. Gonzalez-Gomez P, Bello MJ, Lomas J, Arjona D, Alonso ME, Aminoso C, Lopez-Marin I, Anselmo NP, Sarasa JL, Gutierrez M, Casartelli C, Rey JA. Laboratorio de Oncogenetica Molecular, Dept. C. Experimental, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid Spain. Aberrant hypermethylation occurs in tumour cell CpG islands and is an important pathway for the repression of gene transcription in cancers. We investigated aberrant hypermethylation of 11 genes by methylation-specific polymerase chain reaction (PCR), after treatment of the DNA with bisulphite, and correlated the findings with MYCN amplification and allelic status at 1p in a series of 44 neuroblastic tumours. This tumour series includes five ganglioneuromas (G), one ganglioneuroblastoma (GN) and 38 neuroblastomas (six stage 1 tumours; five stage 2 tumours; six stage 3 cases; 19 stage 4 tumours, and two stage 4S cases). Aberrant methylation of at least one of the 11 genes studied was detected in 95% (42 of 44) of the cases. The frequencies of aberrant methylation were: 64% for thrombospondin-1 (THBS1); 30% for tissue inhibitor of metalloproteinase 3 (TIMP-3); 27% for O6-methylguanine-DNA methyltransferase (MGMT); 25% for p73; 18% for RB1; 14% for death-associated protein kinase (DAPK), p14ARF, p16INK4a and caspase 8, and 0% for TP53 and glutathione S-transferase P1 (GSTP1). No aberrant methylation was observed in four control normal tissue samples (brain and adrenal medulla). MYCN amplification was found in 11 cases (all stage 4 neuroblastomas), whereas allelic loss at 1p was identified in 16 samples (13 stage 4 and two stage 3 neuroblastomas, and one ganglioneuroma). All but one case with caspase 8 methylation also displayed MYCN amplification. Our results suggest that promoter hypermethylation is a frequent epigenetic event in the tumorigenesis of neuroblastic tumours, but no specific pattern of hypermethylated genes could be demonstrated. PMID: 12826052 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 10: Cancer Genet Cytogenet. 2003 Apr 1;142(1):65-9. Molecular cytogenetic analysis of a pleuropulmonary blastoma. Hong B, Chen Z, Coffin CM, Lemons R, Issa B, Brothman A, Zhou H. Cytogenetics Laboratory, University of Utah School of Medicine, 50 North Medical Drive, Salt Lake City, UT 84132, USA. We report a case of pleuropulmonary blastoma with complex cytogenetic abnormalities, including trisomy 2, trisomy 8, dup(7), der(10) t(8; 10)(q13; q22), add(17), and double minutes (dmin). Fluorescence in situ hybridization FISH analysis demonstrated TP53 deletion and amplification of MYCN; the latter has not been reported in PPB. Publication Types: Case Reports PMID: 12660036 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 11: Arch Med Res. 2002 Sep-Oct;33(5):466-72. Study of proliferation and apoptosis in neuroblastoma. Their relation with other prognostic factors. del Carmen Mejia M, Navarro S, Pellin A, Ruiz A, Castel V, Llombart-Bosch A. Departamento de Neurociencias, Instituto de Fisiologia Celular, Universidad Nacional Autonoma de Mexico (UNAM), Mexico City, Mexico. maria.c.mejia@uv.es BACKGROUND: Our objective was to study the proliferation and apoptotic process in 111 cases of neuroblastoma (NB) and to seek their relationship with other prognostic factors and survival. METHODS: Immunohistochemistry following ABC peroxidase was carried out for PCNA, Ki-67, bcl-2, and p53 proteins. Apoptosis analysis was performed with in situ detection of chromosomal breakdown. Molecular detection of DNA ladders by electrophoresis and amplification of MYCN was studied with PCR and Southern blot. Statistical study was performed with Pearson chi(2) and Kruskal-Wallis tests and Cox regression. RESULTS: Our results indicate that proliferative factors PCNA and Ki-67 were correlated to each other as well as to advanced stage and MYCN amplification. Regarding apoptosis, we found expression of bcl-2 protein in cases of NB without differentiation and advanced stages. p53 protein showed an inverse relation with bcl-2 and cell death measured by assay protein. In situ determination of apoptosis was found mainly in differentiated and stage 4s cases. Multivariate analysis revealed protein as the most independent risk factor of our study. CONCLUSIONS: The study of cellular proliferation and apoptosis contributes with information of prognostic value that could be applied to the design of different protocols for treatment of neuroblastoma. PMID: 12459317 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 12: Oncogene. 2002 Mar 14;21(12):1848-58. Caspase-9 and Apaf-1 are expressed and functionally active in human neuroblastoma tumor cell lines with 1p36 LOH and amplified MYCN. Teitz T, Wei T, Liu D, Valentine V, Valentine M, Grenet J, Lahti JM, Kidd VJ. Department of Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, TN 38105, USA. Important roles have been suggested for caspase-8, caspase-9 and Apaf-1 in controlling tumor development and their sensitivity to chemotherapeutic agents. Methylation and deletion of Apaf-1 and CASP8 results in the loss of their expression in melanoma and neuroblastoma, respectively, while CASP9 localization to 1p36.1 suggests it is a good candidate tumor suppressor. The status of CASP9 and Apaf-1 expression in numerous neuroblastoma cell lines with/without amplified MYCN and chromosome 1p36 loss-of-heterozygosity (LOH) was therefore examined to test the hypothesis that one or both of these genes are tumor suppressors in neuroblastoma. Although CASP9 is included in the region encompassing 1p36 LOH in all neuroblastoma cell lines examined, the remaining CASP9 allele(s) express a functional caspase-9 enzyme. Apaf-1 is also expressed in all neuroblastoma tumor cell lines examined. Thus, the CASP9 or Apaf-1 genes do not appear to function as tumor suppressors in MYCN amplified neuroblastomas. However, approximately 20% of the neuroblastoma cell lines with methylated CASP8 alleles are also highly resistant to staurosporine (STS)- and radiation-induced cell death, presumably because cytochrome c is not released from mitochondria. This suggests that a second, smaller sub-group of MYCN amplified neuroblastoma tumors exists with defect(s) in apoptotic signaling components upstream of caspase-9 and Apaf-1. Since no consistent differences in Bcl-2, Bcl-x(L) or Bax expression were seen in the STS- and radiation-resistant neuroblastomas, it suggests that a unique mitochondrial signaling factor(s) is responsible for the defect in cytochrome c release in this sub-group of tumors. PMID: 11896617 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 13: Am J Pathol. 2001 Jun;158(6):2067-77. p53 cellular localization and function in neuroblastoma: evidence for defective G(1) arrest despite WAF1 induction in MYCN-amplified cells. Tweddle DA, Malcolm AJ, Cole M, Pearson AD, Lunec J. Cancer Research Unit, The Medical School, University of Newcastle, Newcastle-upon-Tyne, United Kingdom. d.a.tweedle@newcastle.ac.uk This study investigated the hypothesis that p53 accumulation in neuroblastoma, in the absence of mutation, is associated with functional inactivation, which interferes with downstream mediators of p53 function. To test this hypothesis, p53 expression, location, and functional integrity was examined in neuroblastoma by irradiating 6 neuroblastoma cell lines and studying the effects on p53 transcriptional function, cell cycle arrest, and induction of apoptosis, together with the transcriptional function of p53 after irradiation in three ex vivo primary, untreated neuroblastoma tumors. p53 sequencing showed five neuroblastoma cell lines, two of which were MYCN-amplified, and that all of the tumors were wild-type for p53. p53 was found to be predominantly nuclear before and after irradiation and to up-regulate the p53 responsive genes WAF1 and MDM2 in wild-type p53 cell lines and a poorly-differentiated neuroblastoma, but not a differentiating neuroblastoma or the ganglioneuroblastoma part of a nodular ganglioneuroblastoma in short term culture. This suggests intact p53 transcriptional activity in proliferating neuroblastoma. Irradiation of wild-type p53 neuroblastoma cell lines led to G(1) cell cycle arrest in cell lines without MYCN amplification, but not in those with MYCN amplification, despite induction of WAF1. This suggests MYCN amplification may alter downstream mediators of p53 function in neuroblastoma. PMID: 11395384 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 14: Genes Chromosomes Cancer. 1999 Dec;26(4):275-85. Genes, chromosomes, and rhabdomyosarcoma. Anderson J, Gordon A, Pritchard-Jones K, Shipley J. Unit of Molecular Hematology and Oncology, Institute of Child Health, London, United Kingdom. Rhabdomyosarcomas are a heterogeneous group of malignant tumors and are the most common soft-tissue sarcoma of childhood. Rhabdomyosarcomas resemble developing skeletal muscle, notably in their expression of the MRF family of transcription factors and the PAX3 and PAX7 genes. These PAX genes are also involved through specific translocations, t(2;13)(q35;q14) and variant t(1;13)(p36;q14) in the alveolar subtype, which result in PAX3-FKHR and PAX7-FKHR fusion genes, respectively. The fusion genes are thought critically to affect downstream targets of PAX3 and PAX7 or possibly have novel targets. Similar downstream changes may also be involved in embryonal and fusion gene negative cases. Genomic amplification of such genes as MYCN, MDM2, CDK4, and PAX7-FKHR is a feature mainly of the alveolar subtype, while specific chromosomal gains, including chromosomes 2, 8, 12, and 13, are associated with the embryonal subtype. Loss of alleles and imprinting at 11p15.5 and disruption of genes such as IGF2, ATR, PTC, P16, and TP53 have also been implicated in rhabdomyosarcoma development. Whereas there is now a realistic possibility of cure in the majority of cases, there remains a subset that is resistant to multimodality therapy, including high-dose chemotherapy. Characterization of the defining molecular features of tumors that are likely to behave aggressively represents a particular challenge. Current research is leading toward a better understanding of rhabdomyosarcoma tumorigenesis, which may ultimately result in novel therapeutic strategies that increase the overall cure. Genes Chromosomes Cancer 26:275-285, 1999. Copyright 1999 Wiley-Liss, Inc. Publication Types: Review Review, Tutorial PMID: 10534762 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 15: Int J Mol Med. 1999 Jun;3(6):585-9. Variable expression and absence of mutations in p73 in primary neuroblastoma tumors argues against a role in neuroblastoma development. Ejeskar K, Sjoberg RM, Kogner P, Martinsson T. Department of Clinical Genetics, University of Gothenburg, Sahlgrenska University Hospital/East, S-416 85 Gothenburg, Sweden. In neuroblastoma, a childhood tumor of neural crest, a tumor suppressor gene located at 1p36 has been implicated to play a major role in tumor aggressiveness and clinical prognosis. We have examined 30 different staged primary neuroblastoma tumors using RT-PCR, for expression of the p73 gene located at 1p36.3, and its correlation to other clinical and biological features of these tumors. No correlation between expression of p73 and MYCN-amplification or 1p-deletion could be found, five of ten 1p-deleted tumors showed detectable levels of p73, and no mutations could be detected, neither in the retained alleles nor in any other parts of the material. In five 1p-deleted cases the origin of deletion were determined, two were of maternal and three of paternal origin. Both tumors with maternal 1p-loss showed detectable levels of p73, whereas the three with paternal loss did not. This suggests that p73 is expressed from the paternal allele only in advanced staged neuroblastoma tumors. Furthermore, it suggests absence of correlation between p73-expression and stage in these tumors. In conclusion, we could find no evidence for p73 being the neuroblastoma tumor suppressor gene in 1p36. PMID: 10341287 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 16: Oncogene. 1999 Feb 18;18(7):1479-86. MycN sensitizes neuroblastoma cells for drug-induced apoptosis. Fulda S, Lutz W, Schwab M, Debatin KM. University Children's Hospital, Ulm, Germany. Amplification of the MYCN gene is found in a large proportion of neuroblastoma and considered as an adverse prognostic factor. To investigate the effect of ectopic MycN expression on the susceptibility of neuroblastoma cells to cytotoxic drugs we used a human neuroblastoma cell line harboring tetracycline-controlled expression of MycN. Neither conditional expression of MycN alone nor low drug concentrations triggered apoptosis. However, when acting in concert, MycN and cytotoxic drugs efficiently induced cell death. Apoptosis depended on mitochondrial permeability transition and activation of caspases, since the mitochondrion-specific inhibitor bongkrekic acid and the caspase inhibitor zVAD-fmk almost completely abrogated apoptosis. Loss of mitochondrial transmembrane potential and release of cytochrome c from mitochondria preceded activation of caspase-8 and caspase-3 and cleavage of PARP. CD95 expression was upregulated by treatment with cytotoxic drugs, while MycN cooperated with cytotoxic drugs to increase sensitivity to CD95-induced apoptosis and enhancing CD95-L expression. MycN overexpression and cytotoxic drugs also synergized to induce p53 and Bax protein expression, while Bcl-2 and Bcl-X(L) protein levels remained unchanged. Since amplification of MYCN is usually associated with a poor prognosis, these findings suggest that dysfunctions in apoptosis pathways may be a mechanism by which MycN-induced apoptosis of neuroblastoma cells is inhibited. PMID: 10050884 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 17: Med Pediatr Oncol. 1997 Sep;29(3):206-7. Concomitant p53 mutation and MYCN amplification in neuroblastoma. Manhani R, Cristofani LM, Odone Filho V, Bendit I. Research and Molecular Biology Division, Pro-Sangue Hemocentro de Sao Paulo Foundation, Brazil. The MYCN oncogene is amplified in 20% of childhood neuroblastoma and is associated independently with poor prognosis. Alteration of the p53 tumor supressor gene, in contrast, occurs infrequently in these tumors. In this report, we described a 3-year-old girl with stage IV neuroblastoma. Molecular analysis revealed, both MYCN gene amplification and a point mutation of the p53 tumor supressor gene. To our knowledge, this is the first reported case of neuroblastoma with genetic alterations of both these genes. Publication Types: Case Reports PMID: 9212845 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 18: Oncogene. 1995 Mar 16;10(6):1081-6. Non-syntenic amplification of MDM2 and MYCN in human neuroblastoma. Corvi R, Savelyeva L, Breit S, Wenzel A, Handgretinger R, Barak J, Oren M, Amler L, Schwab M. Division of Cytogenetics, German Cancer Research Center, Heidelberg. Amplification of the MYCN gene is a well documented genetic alteration of aggressively growing human neuroblastomas. Through cytogenetic studies we have identified neuroblastoma cell lines which, in addition to amplified MYCN, carry amplified DNA not harbouring MYCN. In situ hybridization of biotinylated total genomic DNA to metaphase chromosomes of normal human lymphocytes by reverse genomic hybridization revealed the amplified DNA to be derived from chromosome 12 band q13-14. Subsequent filter analyses showed a 20- to 40-fold amplification of the MDM2 gene, located at 12q13-14, both in three cell lines and in an original tumor, in addition to amplified MYCN. As the apparent consequence of amplification abundant MDM2 protein was present, a part of which was complexed with p53. PMID: 7700632 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 19: Eur J Cancer. 1995;31A(4):560-4. Genetic alterations associated with metastatic dissemination and chemoresistance in neuroblastoma. Benard J. Laboratory of Clinical & Molecular Pharmacology, Institut Gustave Roussy, Villejuif, France. Knowledge about genetic alterations specific to the metastatic process and chemoresistance in neuroblastoma is progressing steadily. Low or no CD44 expression, increased NM23 expression and specific mutations of the 5' coding regions of NM23 are distinct features of aggressive, metastatic neuroblastoma. MYCN down-regulates Class I HLA antigen expression in many neuroblastoma cell lines and, in turn, may be regulated by a suppressor gene. The MYCN amplified human neuroblastoma cell line, IGR-N-91, established in vitro, metastasises in the nude mouse and has exhibited co-activation of MYCN and PGY1, resulting from direct activation of the oncoprotein on the PGY1 promoter. In this model, the MYCN product activates angiogenesis, the dissemination process and chemoresistance via specific genes (PGY1 and GST3). MYCN, like the BCL-2 and TP53 products, may also play a key role in apoptosis. The implication of these genes in the potential for metastasis and chemoresistance in neuroblastoma is discussed. Publication Types: Review Review, Tutorial PMID: 7576968 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 20: Pediatr Hematol Oncol. 1994 Jul-Aug;11(4):361-77. Cytogenetic analysis in the examination of solid tumors in children. Mertens F, Mandahl N, Mitelman F, Heim S. Department of Clinical Genetics, University Hospital, Lund, Sweden. Although pediatric solid tumors are cytogenetically less well characterized than childhood leukemias, an understanding of the role of chromosomal changes in the development of these neoplasms is emerging. The major clinical importance of chromosome analysis today is diagnostic. Especially in small cell round cell tumors of childhood, the unique karyotypic patterns that characterize some of the differential diagnostic entities make it possible to determine with a high degree of certainty which type of cancer the child has. Molecular studies have revealed that almost all retinoblastomas show homozygous loss of function of the RB1 gene in 13q14. At the cytogenetic level, however, aberrations of 13q are seen in less than 25% of retinoblastomas; instead, the presumably progression-related i(6p) and aberrations leading to gain of 1q predominate, each being present in one-third of the tumors. Twenty percent of cytogenetically aberrant Wilms' tumors show structural rearrangements, often deletions, of 11p13 and 11p15, where the WT1 and WT2 genes map. Other frequent changes are trisomy 12 and duplication of 1q. The most common (80%) cytogenetic abnormality in neuroblastoma is loss of distal 1p, a chromosome segment thought to harbor at least two tumor-suppressor genes of importance in tumorigenesis. Double minute chromosomes or homogeneously staining regions are present in one-third of all neuroblastomas and are associated with MYCN amplification. Loss of 1p material or MYCN amplification predicts a poor outcome. The most common (30%) chromosomal aberration in primitive neuroectodermal tumors of the central nervous system is i(17q). The formation of this isochromosome may help inactivate a tumor-suppressor gene located distal to the TP53 locus on 17p. No specific chromosome abnormality has been detected in gliomas, but monosomy 22 and rearrangements leading to loss of 1p and gain of 1q are recurrent. Few hepatoblastomas with chromosomal changes have been reported, but several potential primary aberrations have been described, including +2, +20, and duplication 8q. In Ewing's sarcoma, t(11;22)(q24;q12) is the primary aberration, with trisomy 8 and gain of 1q being frequent secondary changes. Fibrosarcomas in children often carry only numeric aberrations, especially trisomy for chromosomes 11, 20, 17, and 8. Most osteosarcomas are cytogenetically complex, and no specific abnormality has been detected; the single most common change is loss of chromosome 13, which is observed in half the tumors. In contrast, the low-malignancy parosteal osteosarcomas often display supernumerary ring chromosomes as the sole karyotypic deviation. The cytogenetic profiles of rhabdomyosarcomas differ among the various morphologic subtypes.(ABSTRACT TRUNCATED AT 400 WORDS) Publication Types: Review Review, Tutorial PMID: 7947009 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 21: Cancer Res. 1992 Mar 1;52(5):1322-8. Chromosome alterations in human small cell lung cancer: frequent involvement of 5q. Miura I, Graziano SL, Cheng JQ, Doyle LA, Testa JR. Department of Medical Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111. Deletions of the 3p chromosome region and molecular alterations of the tumor suppressor genes RB1 and TP53, located, respectively, at 13q14 and 17p13, are well-documented in small cell lung cancer (SCLC). Because of technical difficulties, karyotypes of primary SCLC specimens are rarely reported. In this study, detailed cytogenetic analysis was performed on 13 early passage SCLC cell lines and fresh specimens, including 4 lung primaries. Numerous chromosome alterations were found, even in newly diagnosed primary tumors. Consistent with previous molecular studies, chromosomal losses of 3p (13 cases) and 17p13 (12 cases) were frequently observed. Numerical losses of chromosome 13 and structural rearrangements affecting 13q14 were identified in 10 specimens. In addition, losses of chromosome 5 and structural alterations of 5q occurred in 12 tumors; among these, 9 displayed losses of region 5q13-q21. Double minutes were found in 4 cases (3 of 5 specimens from patients who received prior cytotoxic therapy but only 1 of 8 from untreated patients). DNA analysis revealed amplification of either MYC1 or MYCN in cells from each of these 4 tumors. Overall, the cytogenetic findings underscore that progression of SCLC involves multiple genetic changes and suggest further that a tumor suppressor gene(s) on 5q may contribute to SCLC tumorigenesis. PMID: 1346589 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 22: Br J Cancer. 1991 Jun;63(6):851-8. Oncogenes in human testicular cancer: DNA and RNA studies. Peltomaki P, Alfthan O, de la Chapelle A. Department of Medical Genetics, University of Helsinki, Finland. Oncogene dosage and expression were studied in 16 testicular neoplasms, 14 of germ cell and two of non-germ cell origin. In comparison with normal DNA, tumour DNA of a total of eight patients (seven with germ cell neoplasm and one with testicular lymphoma) showed increased dosages of KRAS2, PDGFA, EGFR, MET and PDGFB. The most frequent (occurring in six tumours) and prominent (up to 3-4-fold) increases were detected in the dosages of KRAS2 (on chromosome 12p) and PDGFA (chromosome 7p), relative to a reference locus from chromosome 2. Importantly, there was a similar increase in 12p dosage in general in these tumours, suggesting the presence of the characteristic isochromosome 12p marker. On the contrary, possible 7p polysomy (assessed by molecular methods) did not explain the PDGFA (or EGFR) changes in all cases. NRAS, MYCN, CSFIR, MYB, MYC, ABL, HRASI, TP53, and ERBB2 did not reveal any consistent alterations in tumour DNA. In RNA dot blot assays the expression of KRAS2, PDGFA, EGFR, or MYC was generally not increased in the tumour samples when compared to that in normal testicular tissue of the same patients although there was interindividual variation in mRNA levels. It thus appears that while oncogene dosage changes occur in a proportion of testis cancers, they are often part of changes in large chromosomal regions or whole arms and are seldom accompanied by altered expression. PMID: 1829952 [PubMed - indexed for MEDLINE] ---------------------------------------------------------------