BCOR expression in paediatric pineoblastoma

BCOR is expressed in a new brain tumour entity, i.e. 'CNS tumour with BCOR internal tandem duplication' (HGNET BCOR) but not in several other high grade paediatric brain tumours investigated. Immunohistochemical detection of BCOR expression may therefore serve as a potential diagnostic marker. Nevertheless, in rare paediatric glioma cases recurrent EP300-BCOR fusions were detected, which resulted in strong BCOR immunopositivity. We have therefore examined other, not analysed so far, types of central nervous system (CNS) tumours, pineoblastoma and germinoma, to assess a potential involvement of BCOR in these tumours. Levels of BCOR RNA expression were investigated by NanoString nCounter system analysis in a series of altogether 66 high grade paediatric tumours, including four pineoblastoma cases. Immunohistological detection of BCOR was performed in eight pineoblastoma, five germinoma and four atypical teratoid rhabdoid tumours (ATRTs), all located in the pineal region. We detected BCOR expression in all pineoblastomas, at the RNA and protein levels, but not in germinomas and ATRTs. Further analysis of pineoblastoma samples did not reveal the presence of either BCOR internal tandem duplication or BCOR fusion involvement. Positive immunohistological BCOR nuclear reaction in pineoblastoma may therefore differentiate this type of tumour from other high grade tumours located in the pineal region.

RARE-15. Astroblastoma, MN1 altered comprises two molecularly and clinically distinct subgroups defined by the fusion partners BEND2 and CXXC5

In the recent 5th edition of the WHO classification of CNS tumors, ‘Astroblastoma, MN1 altered’ is recognized a distinct brain tumor type, occurring in children and young adults. Due to its rarity and novelty, little is known about clinical and molecular traits. Therefore, we initiated an international effort and collected tissue samples, clinical and molecular data from 176 patients with Astroblastoma, MN1 altered, identified by their distinct DNA methylation profiles. DNA methylation-based t-SNE clustering analyses revealed that Astroblastoma, MN1 altered tumors form one distinct main cluster (n=158) showing MN1:BEND2 and single cases with EWSR1:BEND2 fusions and a further adjacent, but distinct smaller cluster (n=18) mostly defined by MN1:CXXC5 fusions. Both fusion partner-defined groups show a median age of 12 years but distinct copy-number aberrations, characteristically a gain of chromosome 5 in one third of the CXXC5-fused group and a loss of chromosome 16q in one third of BEND2-fused cases. As previously reported, a vast majority of Astroblastoma, MN1 altered patients are female, which we confirm for the BEND2-fused group (85%). The CXXC5-fused group, however, shows 75% male patients. Interestingly, 9/10 tumors of the few male patients observed in the BEND2-fused group were all located infratentorially or in the spinal cord, whereas almost all female cases show a supratentorial location (85/87). Histologically, the BEND2-fused group was primarily reported as Astroblastoma (39%), whereas in the CXXC5-fused cases, 31% CNS-PNET and only 8% Astroblastoma histologies were originally assigned. Preliminary clinical analyses showed that the BEND2-fused group has a relatively good 5/10-year OS of 97%/89%, but a less favorable 5/10-year PFS of 48%/35%, in line with previous studies. Patients showing CXXC5-fused tumors (n=8) indicated 5/10-year OS and PFS rates of 83%/83% and 60%/60%, respectively. Additional survival and molecular analyses are being conducted to further characterize Astroblastoma, MN1 altered tumors and its molecular subgroups.

ETMR-06. Molecular and clinical characteristics of CNS tumors withBCOR(L1) fusion/internal tandem duplication

Central nervous system (CNS) tumor with BCOR internal tandem duplication (BCOR-ITD) have recently been introduced in the 5th edition of the WHO classification of CNS tumors, however, their molecular makeup and clinical characteristics remain widely enigmatic. This is further complicated by the recent discovery of tumors characterized by gene fusions involving BCOR or its homologue BCORL1. We identified a cohort of 206 BCOR altered CNS tumors via DNA methylation profiling and conducted in-depth molecular and clinical characterization in an international effort. By performing t-SNE clustering analysis we found that BCOR-fusion tumors form a distinct cluster (n=61), adjacent to BCOR-ITD cases (n=145). The identified fusion partners of BCOR(L1) included EP300 (n=20), CREBBP (n=5), and NUTM2HP (n=1). Notably, three cases within the BCOR-ITD cluster harbored a c-terminal intragenic deletion within BCOR. With respect to clinical characteristics gender ratio was balanced in BCOR-fusion cases (m/f, 1.1), whereas predominance of male patients was observed in the BCOR-ITD group (m/f, 1.5). Moreover, age at diagnosis of BCOR-fusion patients was higher as compared to BCOR-ITD cases (15 vs 4.5 years). Interestingly, BCOR-fusion tumors were exclusively found in the supratentorial region being originally diagnosed as ependymomas or gliomas whereas BCOR-ITD emerged across the entire CNS with diverse original diagnoses. 8% of BCOR-ITD and none of BCOR-fusion cases were disseminated at diagnosis. In line with this observation, 40% of first relapses within the BCOR-ITD group were metastatic which was less frequent in BCOR-fusion tumors. Survival estimates demonstrated no differences, generally showing short median PFS (BCOR-fusion, 2 years, n=15; BCOR-ITD, 1.8 years, n=55) and intermediate OS rates (BCOR-fusion, 6.8 years, n=18; BCOR-ITD 6.3 years, n=60). Further molecular and clinical characterization is ongoing potentially revealing first therapeutic leads for these highly aggressive CNS tumor types.

Transcriptional profiling of paediatric ependymomas identifies prognostically significant groups

The majority of supratentorial ependymomas in children contain oncogenic fusions, such as ZFTA-RELA or YAP1-MAMLD1. In contrast, posterior fossa (PF) ependymomas lack recurrent somatic mutations and are classified based on gene expression or methylation profiling into group A (PFA) and group B (PFB). We have applied a novel method, NanoString nCounter Technology, to identify four molecular groups among 16 supratentorial and 50 PF paediatric ependymomas, using 4-5 group-specific signature genes. Clustering analysis of 16 supratentorial ependymomas revealed 9 tumours with a RELA fusion-positive signature (RELA+), 1 tumour with a YAP1 fusion-positive signature (YAP1+), and 6 not-classified tumours. Additionally, we identified one RELA+ tumour among historically diagnosed CNS primitive neuroectodermal tumour samples. Overall, 9 of 10 tumours with the RELA+ signature possessed the ZFTA-RELA fusion as detected by next-generation sequencing (p = 0.005). Similarly, the only tumour with a YAP1+ signature exhibited the YAP1-MAMLD1 fusion. Among the remaining unclassified ependymomas, which did not exhibit the ZFTA-RELA fusion, the ZFTA-MAML2 fusion was detected in one case. Notably, among nine ependymoma patients with the RELA+ signature, eight survived at least 5 years after diagnosis. Clustering analysis of PF tumours revealed 42 samples with PFA signatures and 7 samples with PFB signatures. Clinical characteristics of patients with PFA and PFB ependymomas corroborated the previous findings. In conclusion, we confirm here that the NanoString method is a useful single tool for the diagnosis of all four main molecular groups of ependymoma. The differences in reported survival rates warrant further clinical investigation of patients with the ZFTA-RELA fusion.

Therapeutic implications of improved molecular diagnostics for rare CNS-embryonal tumor entities: results of an international, retrospective study

BACKGROUND

Only few data are available on treatment-associated behavior of distinct rare CNS-embryonal tumor entities previously treated as "CNS-primitive neuroectodermal tumors" (CNS-PNET). Respective data on specific entities, including CNS neuroblastoma, FOXR2 activated (CNS NB-FOXR2), and embryonal tumor with multi-layered rosettes (ETMR) are needed for development of differentiated treatment strategies.

METHODS

Within this retrospective, international study, tumor samples of clinically well-annotated patients with the original diagnosis of CNS-PNET were analyzed using DNA methylation arrays (n=307). Additional cases (n=66) with DNA methylation pattern of CNS NB-FOXR2 were included irrespective of initial histological diagnosis. Pooled clinical data (n=292) were descriptively analyzed.

RESULTS

DNA methylation profiling of "CNS-PNET" classified 58(19%) cases as ETMR, 57(19%) as HGG, 36(12%) as CNS NB-FOXR2, and 89(29%) cases were classified into 18 other entities. Sixty-seven (22%) cases did not show DNA methylation patterns similar to established CNS tumor reference classes. Best treatment results were achieved for CNS NB-FOXR2 patients (5-year PFS: 63%±7%, OS: 85%±5%, n=63), with 35/42 progression-free survivors after upfront craniospinal irradiation (CSI) and chemotherapy. The worst outcome was seen for ETMR and HGG patients with 5-year PFS of 18%±6% and 22%±7%, and 5-year OS of 24%±6% and 25%±7%, respectively.

CONCLUSION

The historically reported poor outcome of CNS-PNET patients becomes highly variable when tumors are molecularly classified based on DNA methylation profiling. Patients with CNS NB-FOXR2 responded well to current treatments and a standard-risk-CSI based regimen may be prospectively evaluated. The poor outcome of ETMR across applied treatment strategies substantiates the necessity for evaluation of novel treatments.

HGG-21. GERMLINE MUTATIONS IN MSH2 GENE IN PEDIATRIC PATIENTS WITH CONGENITAL AND SPORADIC GLIOBLASTOMA

INTRODUCTION

Glioblastoma (GBM) remains one of the biggest therapeutic challenges in neuro-oncology. In spite of multimodal treatment approaches the prognosis of GBM is extremely poor, median survival is estimated about 12–16 months. Although GBM is one of the most common and malignant primary brain tumors, pediatric glioblastoma, including congenital is a very rare tumor, with an incidence of about 1.1–3.4 per million live births. Moreover, the mode of presentation, behavior, response to therapy and molecular background of pediatric glioblastomas differs from adult type of GBM. Until now, about ten patients with congenital glioblastoma have been described and in none of them germline markers were examined. Here we report two patients with GBM, one with congenital tumor with germline mutations in MSH2 gene.

METHODS

Targeted Next-Generation Sequencing (NGS) of the probands DNA extracted from leucocytes was performed using the TruSight One sequencing panel on an Illumina HiSeq 1500. Applied gene panel investigated the coding sequence and splice sites of 4813 genes associated with known disease phenotypes. The NGS data were analyzed using an in-house procedure. Identified variants were validated by Sanger sequencing.

RESULTS

NGS analysis of patients constitutional DNA revealed know, pathogenic variants c.940C>T and c.942 + 3A>T in MSH2 gene (NM_000251.3) associated with MMR-dependent hereditary cancer syndromes.

CONCLUSION

Molecular analysis are heavily needed for better understanding of pediatric GBM etiology and new treatment modality implementation. Identification of this oncogenic driver may provide insight into the pathogenesis of GBM, including congenital cases. Funded by National Science Centre, Poland (2016/23/B/NZ2/03064 and 2016/21/B/NZ2/01785).

Molecular identification of CNS NB-FOXR2, CNS EFT-CIC, CNS HGNET-MN1 and CNS HGNET-BCOR pediatric brain tumors using tumor-specific signature genes

Four molecular types of rare central nervous system (CNS) tumors have been recently identified by gene methylation profiling: CNS Neuroblastoma with FOXR2 activation (CNS NB-FOXR2), CNS Ewing Sarcoma Family Tumor with CIC alteration (CNS EFT-CIC), CNS high grade neuroepithelial tumor with MN1 alteration (CNS HGNET-MN1) and CNS high grade neuroepithelial tumor with BCOR alteration (CNS HGNET-BCOR). Although they are not represented in 2016 updated WHO classification of CNS tumors, their diagnostic recognition is important because of clinical consequences. We have introduced a diagnostic method based on transcription profiling of tumor specific signature genes from formalin-fixed, paraffin-embedded tumor blocks using NanoString nCounter Technology. Altogether, 14 out of 187 (7.4%) high grade pediatric brain tumors were diagnosed with either of four new CNS categories. Histopathological examination of the tumors confirmed, that they demonstrate a spectrum of morphology mimicking other CNS high grade tumors. However, they also exhibit some suggestive histopathological and immunohistochemical features that allow for a presumptive diagnosis prior to molecular assessment. Clinical characteristics of patients corroborated with the previous findings for CNS EFT-CIC, CNS NB-FOXR2 and CNS HGNET-MN1 patients, with a favorable survival rate for the latter two groups. Among six CNS HGNET-BCOR patients, three patients are long term survivors, suggesting possible heterogeneity within this molecular category of tumors. In summary, we confirmed the effectiveness of NanoString method using a single, multi-gene tumor specific signature and recommend this novel approach for identification of either one of the four newly described CNS tumor entities.

The molecular landscape of ETMR at diagnosis and relapse

Embryonal tumours with multilayered rosettes (ETMRs) are aggressive paediatric embryonal brain tumours with a universally poor prognosis1. Here we collected 193 primary ETMRs and 23 matched relapse samples to investigate the genomic landscape of this distinct tumour type. We found that patients with tumours in which the proposed driver C19MC2-4 was not amplified frequently had germline mutations in DICER1 or other microRNA-related aberrations such as somatic amplification of miR-17-92 (also known as MIR17HG). Whole-genome sequencing revealed that tumours had an overall low recurrence of single-nucleotide variants (SNVs), but showed prevalent genomic instability caused by widespread occurrence of R-loop structures. We show that R-loop-associated chromosomal instability can be induced by the loss of DICER1 function. Comparison of primary tumours and matched relapse samples showed a strong conservation of structural variants, but low conservation of SNVs. Moreover, many newly acquired SNVs are associated with a mutational signature related to cisplatin treatment. Finally, we show that targeting R-loops with topoisomerase and PARP inhibitors might be an effective treatment strategy for this deadly disease.

OLIG2 is a novel immunohistochemical marker associated with the presence of PAX3/7-FOXO1 translocation in rhabdomyosarcomas

BACKGROUND

The most frequent histological types of rhabdomyosarcoma (RMS) in children are embryonal (ERMS) and alveolar (ARMS) tumours. The majority of ARMS are characterized by the presence of PAX3/7-FOXO1 gene fusion and have a worse prognosis than fusion gene-negative ARMS. However, identification of PAX3/7-FOXO1 fusion status is challenging when using formalin-fixed, paraffin-embedded (FFPE) material. Microarray analyses revealed that high expression of several genes is associated with PAX3/7-FOXO1 fusion status. Therefore, we investigated if immunohistochemical approach may detect surrogate marker genes as indicators of fusion gene-positive RMS.

METHODS

Forty five RMS patients were included in the analysis and immunohistochemistry was applied to FFPE tissues collected at diagnosis. Protein expression of OLIG2, a novel marker in RMS, was investigated using antibody EP112 (Cell Marque). In addition already known two markers were also analyzed: TFAP2B using rabbit anti-TFAP2β antibody (Santa Cruz Biotechnology) and ALK using anti-ALK antibody clone D5F3 #3633 (Cell Signalling). Fluorescence in situ hybridization (FISH) was performed on FFPE sections with FOXO1/PAX3 and/or FOXO1/PAX7 probes (Dual Colour Single Fusion Probe, Zytovision).

RESULTS

Our analysis revealed that all three immunohistochemical markers are associated with the presence of PAX3/7-FOXO1 fusion: TFAP2B (p < 0.00001), OLIG2 (p = 0.0001) and ALK (p = 0.0007). Four ARMS had negative PAX3/7-FOXO1 status and none of them displayed positive reaction with the analysed markers. Positive reaction with OLIG2 (6 tumours) was always associated with the presence of PAX3/7-FOXO1 rearrangement. Two additional OLIG2 positive cases showed inconclusive FISH results, but were positive for TFAP2B and ALK, what suggests that these tumours expressed fusion positive signature.

CONCLUSION

Our results indicate that TFAP2B, ALK and a novel marker OLIG2 may serve as surrogate markers for PAX3/7-FOXO1 status what is especially beneficial in cases where poor quality tumour tissue is not suitable for reliable genetic analyses or shows inconclusive result.

P13.04 Transcriptional profiling differentiates spinal cord ependymal tumours from other glial tumours in children

BACKGROUND

Spinal cord tumours in children include ependymal and other tumours of glial origin, all of them displaying GFAP marker. Some tumours may present difficulties in histopathological diagnosis e.g. due to intratumour heterogeneity. Therefore, molecular approach should be examined for its diagnostic usefulness. We investigated a series of originally diagnosed spinal cord ependymal tumours, using transcriptional profiling, to confirm if molecular classification is compatible with histopathological diagnosis.

MATERIAL AND METHODS

Overall, 9 patients diagnosed between 2001 and 2014 in The Children’s Memorial Health Institute (CMHI) in Warsaw, Poland, were included in the analysis. 4 patients were diagnosed with GI myxopapillary ependymomas, 3 patients with GII and 2 patients with GIII grade ependymal tumours. Total RNA was extracted from FFPE tumour samples using RNeasy kits (Qiagen). Transcriptional profiling was performed using NanoString nCounter system analysis. Tumours were analysed according to the manufacturer’s procedures for hybridization, detection and scanning. Raw counts for each gene underwent technical and biological normalization using nSolver software. A custom NanoString CodeSet consisted of 8 marker genes: GFAP as a glial marker, CAPS and FAM81B as the markers for ependymal tumours and OLIG1, OLIG2, PMP2, KLRC3 and C1orf61 as the markers for other gliomas. Marker genes were identified by re-analysis of publically available microarrays data from childhood brain tumour samples. Histopathological reassessment of tumour preparations was performed by two experienced neuropathologists.

RESULTS

Hierarchical clustering of 9 samples revealed that two tumours clustered separately and displayed low expression of ependymal markers but high expression of all other glioma markers. Subsequent histopathological re-analysis of preparation of the later 2 tumours showed that one of them displayed features of pilocytic astrocytoma with loose, microcytic and fibrillary areas accompanied by advanced myxoid degenerative changes mimicking the picture of myxopapillary ependymoma. The second tumour revealed heterogeneous morphology with areas of diffuse low grade astrocytoma, pilocytic astrocytoma and fragments displaying ependymal features, including angiocentric pattern with ependymoma-like perivascular arrangement of neoplastic cells.

CONCLUSION

The results of analysis indicate that RNA expression profiling from FFPE tumour samples using NanoString nCounter system may be a useful approach in differentiation of ependymal tumours from other glial tumours with misleading morphology located in the spinal cord in children. Funded by the National Science Centre, Poland (2016/21/B/NZ2/01785 and 2016/23/B/NZ2/03064).

Medulloblastoma with transitional features between Group 3 and Group 4 is associated with good prognosis

Medulloblastoma, the most common malignant pediatric brain tumor, is a heterogeneous disease, with the existence of at least four molecular types: Wingless (WNT), Sonic Hedgehog (SHH), Group 3 and Group 4 tumors. The latter two groups, which can be identified by an application of multi-gene expression or methylation profiling, show sometimes ambiguous categorization and are still classified for diagnostic reason as non-SHH/non-WNT medulloblastomas in updated WHO 2016 classification. In order to better characterize non-SHH/non-WNT tumors, we applied the method based on the Nanostring nCounter Technology, using the 26 genes codeset in 68 uniformly treated medulloblastoma patients. This allowed for identification of tumors, which shared common Group 3 and Group 4 gene signatures. We recognized three transcriptional groups within non-WNT/non-SHH tumors: Group 3, Group 4 and the Intermediate 3/4 Group. Group 3, in line with previously published results, showed poor prognosis with survival rate < 40%, frequent metastases, large cell/anaplastic pathology and presence of tumors with MYCC amplification. This is in contrast to patients from the Intermediate 3/4 Group who showed the best survival rate (100%). Overall and progression free survival were better for this group than for Group 3 (p = 0.001, for both) and Group 4 (p = 0.064 and p = 0.066, respectively). Our work supports the view that within the non-WNT/non-SHH tumors different risk groups exist and that the current two groups classifier may be not sufficient for proper clinical categorization of individual patients.

Constitutional mosaicism of a de novo TP53 mutation in a patient with bilateral choroid plexus carcinoma

Choroid plexus tumors (CPT) constitute 2%-5% of all pediatric brain tumors and include high grade choroid plexus carcinoma (CPC). About 40% of CPC patients harbor germline TP53 mutations, associated with diminished survival rates. However, the number of TP53 carriers might be underestimated due to suboptimal ability of Sanger sequencing to identify mosaicism. We describe an 18-month-old boy with ultra-rare, bilateral disseminated CPC and negative family history of cancer. Next generation sequencing (NGS) revealed constitutional mosaicism of de novo TP53 mutation, which was barely detectable by Sanger sequencing. This is the first description of a de novo TP53 mutation mosaicism in a patient with CPC. Up to now four cases of de novo TP53 mutations in CPC patients have been described but none of them were mosaic. Since TP53 mutation mosaicism may have an impact on management of patients and predisposition to other cancers, a reliable method of identification is important. Our results highlight the utility of high-throughput technologies in detection of potentially important genetic markers.

The germline variants in DNA repair genes in pediatric medulloblastoma: a challenge for current therapeutic strategies

BACKGROUND

The defects in DNA repair genes are potentially linked to development and response to therapy in medulloblastoma. Therefore the purpose of this study was to establish the spectrum and frequency of germline variants in selected DNA repair genes and their impact on response to chemotherapy in medulloblastoma patients.

METHODS

The following genes were investigated in 102 paediatric patients: MSH2 and RAD50 using targeted gene panel sequencing and NBN variants (p.I171V and p.K219fs*19) by Sanger sequencing. In three patients with presence of rare life-threatening adverse events (AE) and no detected variants in the analyzed genes, whole exome sequencing was performed. Based on combination of molecular and immunohistochemical evaluations tumors were divided into molecular subgroups. Presence of variants was tested for potential association with the occurrence of rare life-threatening AE and other clinical features.

RESULTS

We have identified altogether six new potentially pathogenic variants in MSH2 (p.A733T and p.V606I), RAD50 (p.R1093*), FANCM (p.L694*), ERCC2 (p.R695C) and EXO1 (p.V738L), in addition to two known NBN variants. Five out of twelve patients with defects in either of MSH2, RAD50 and NBN genes suffered from rare life-threatening AE, more frequently than in control group (p = 0.0005). When all detected variants were taken into account, the majority of patients (8 out of 15) suffered from life-threatening toxicity during chemotherapy.

CONCLUSION

Our results, based on the largest systematic study performed in a clinical setting, provide preliminary evidence for a link between defects in DNA repair genes and treatment related toxicity in children with medulloblastoma. The data suggest that patients with DNA repair gene variants could need special vigilance during and after courses of chemotherapy.

New Brain Tumor Entities Emerge from Molecular Classification of CNS-PNETs

Primitive neuroectodermal tumors of the central nervous system (CNS-PNETs) are highly aggressive, poorly differentiated embryonal tumors occurring predominantly in young children but also affecting adolescents and adults. Herein, we demonstrate that a significant proportion of institutionally diagnosed CNS-PNETs display molecular profiles indistinguishable from those of various other well-defined CNS tumor entities, facilitating diagnosis and appropriate therapy for patients with these tumors. From the remaining fraction of CNS-PNETs, we identify four new CNS tumor entities, each associated with a recurrent genetic alteration and distinct histopathological and clinical features. These new molecular entities, designated "CNS neuroblastoma with FOXR2 activation (CNS NB-FOXR2)," "CNS Ewing sarcoma family tumor with CIC alteration (CNS EFT-CIC)," "CNS high-grade neuroepithelial tumor with MN1 alteration (CNS HGNET-MN1)," and "CNS high-grade neuroepithelial tumor with BCOR alteration (CNS HGNET-BCOR)," will enable meaningful clinical trials and the development of therapeutic strategies for patients affected by poorly differentiated CNS tumors.

Abstracts from the 3rd International Genomic Medicine Conference (3rd IGMC 2015) : Jeddah, Kingdom of Saudi Arabia. 30 November - 3 December 2015

O1 Regulation of genes by telomere length over long distances

Jerry W. Shay

O2 The microtubule destabilizer KIF2A regulates the postnatal establishment of neuronal circuits in addition to prenatal cell survival, cell migration, and axon elongation, and its loss leading to malformation of cortical development and severe epilepsy

Noriko Homma, Ruyun Zhou, Muhammad Imran Naseer, Adeel G. Chaudhary, Mohammed Al-Qahtani, Nobutaka Hirokawa

O3 Integration of metagenomics and metabolomics in gut microbiome research

Maryam Goudarzi, Albert J. Fornace Jr.

O4 A unique integrated system to discern pathogenesis of central nervous system tumors

Saleh Baeesa, Deema Hussain, Mohammed Bangash, Fahad Alghamdi, Hans-Juergen Schulten, Angel Carracedo, Ishaq Khan, Hanadi Qashqari, Nawal Madkhali, Mohamad Saka, Kulvinder S. Saini, Awatif Jamal, Jaudah Al-Maghrabi, Adel Abuzenadah, Adeel Chaudhary, Mohammed Al Qahtani, Ghazi Damanhouri

O5 RPL27A is a target of miR-595 and deficiency contributes to ribosomal dysgenesis

Heba Alkhatabi

O6 Next generation DNA sequencing panels for haemostatic and platelet disorders and for Fanconi anaemia in routine diagnostic service

Anne Goodeve, Laura Crookes, Nikolas Niksic, Nicholas Beauchamp

O7 Targeted sequencing panels and their utilization in personalized medicine

Adel M. Abuzenadah

O8 International biobanking in the era of precision medicine

Jim Vaught

O9 Biobank and biodata for clinical and forensic applications

Bruce Budowle, Mourad Assidi, Abdelbaset Buhmeida

O10 Tissue microarray technique: a powerful adjunct tool for molecular profiling of solid tumors

Jaudah Al-Maghrabi

O11 The CEGMR biobanking unit: achievements, challenges and future plans

Abdelbaset Buhmeida, Mourad Assidi, Leena Merdad

O12 Phylomedicine of tumors

Sudhir Kumar, Sayaka Miura, Karen Gomez

O13 Clinical implementation of pharmacogenomics for colorectal cancer treatment

Angel Carracedo, Mahmood Rasool

O14 From association to causality: translation of GWAS findings for genomic medicine

Ahmed Rebai

O15 E-GRASP: an interactive database and web application for efficient analysis of disease-associated genetic information

Sajjad Karim, Hend F Nour Eldin, Heba Abusamra, Elham M Alhathli, Nada Salem, Mohammed H Al-Qahtani, Sudhir Kumar

O16 The supercomputer facility “AZIZ” at KAU: utility and future prospects

Hossam Faheem

O17 New research into the causes of male infertility

Ashok Agarwa

O18 The Klinefelter syndrome: recent progress in pathophysiology and management

Eberhard Nieschlag, Joachim Wistuba, Oliver S. Damm, Mohd A. Beg, Taha A. Abdel-Meguid, Hisham A. Mosli, Osama S. Bajouh, Adel M. Abuzenadah, Mohammed H. Al-Qahtani

O19 A new look to reproductive medicine in the era of genomics

Serdar Coskun

P1 Wnt signalling receptors expression in Saudi breast cancer patients

Muhammad Abu-Elmagd, Abdelbaset Buhmeida, Ashraf Dallol, Jaudah Al-Maghrabi, Sahar Hakamy, Wejdan Al-Qahtani, Asia Al-Harbi, Shireen Hussain, Mourad Assidi, Mohammed Al-Qahtani, Adel Abuzenadah

P2 Analysis of oxidative stress interactome during spermatogenesis: a systems biology approach to reproduction

Burak Ozkosem, Rick DuBois

P3 Interleukin-18 gene variants are strongly associated with idiopathic recurrent pregnancy loss.

Safia S Messaoudi, Maryam T Dandana, Touhami Mahjoub, Wassim Y Almawi

P4 Effect of environmental factors on gene-gene and gene-environment reactions: model and theoretical study applied to environmental interventions using genotype

S. Abdalla, M. Nabil Al-Aama

P5 Genomics and transcriptomic analysis of imatinib resistance in gastrointestinal stromal tumor

Asmaa Elzawahry, Tsuyoshi Takahashi, Sachiyo Mimaki, Eisaku Furukawa, Rie Nakatsuka, Isao Kurosaka, Takahiko Nishigaki, Hiromi Nakamura, Satoshi Serada, Tetsuji Naka, Seiichi Hirota, Tatsuhiro Shibata, Katsuya Tsuchihara, Toshirou Nishida, Mamoru Kato

P6 In-Silico analysis of putative HCV epitopes against Pakistani human leukocyte antigen background: an approach towards development of future vaccines for Pakistani population

Sajid Mehmood, Naeem Mahmood Ashraf, Awais Asif, Muhammad Bilal, Malik Siddique Mehmood, Aadil Hussain

P7 Inhibition of AChE and BuChE with the natural compounds of Bacopa monerri for the treatment of Alzheimer’s disease: a bioinformatics approach

Qazi Mohammad Sajid Jamal, Mughees Uddin Siddiqui, Mohammad A. Alzohairy, Mohammad A. Al Karaawi

P8 Her2 expression in urothelial cell carcinoma of the bladder in Saudi Arabia

Taoufik Nedjadi, Jaudah Al-Maghrabi, Mourad Assidi, Heba Al-Khattabi, Adel Al-Ammari, Ahmed Al-Sayyad, Abdelbaset Buhmeida, Mohammed Al-Qahtani

P9 Association of angiotensinogen single nucleotide polymorphisms with Preeclampsia in patients from North Africa

Hédia Zitouni, Nozha Raguema, Marwa Ben Ali, Wided Malah, Raja Lfalah, Wassim Almawi, Touhami Mahjoub

P10 Systems biology analysis reveals relations between normal skin, benign nevi and malignant melanoma

Mohammed Elanbari, Andrey Ptitsyn

P11 The apoptotic effect of thymoquinone in Jurkat cells

Sana Mahjoub, Rabeb El Ghali, Bechir Achour, Nidhal Ben Amor, Mourad Assidi, Brahim N'siri, Hamid Morjani

P12 Sonic hedgehog contributes in bladder cancer invasion in Saudi Arabia

Taoufik Nedjadi, Adel Al-Ammari, Ahmed Al-Sayyad, Nada Salem, Esam Azhar, Jaudah Al-Maghrabi

P13 Association of Interleukin 18 gene promoter polymorphisms - 607A/C and -137 G/C with colorectal cancer onset in a sample of Tunisian population

Vera Chayeb, Maryam Dendena, Hedia Zitouni, Khedija Zouari-Limayem, Touhami Mahjoub

P14 Pathological expression of interleukin-6, -11, leukemia inhibitory factor and their receptors in tubal gestation with and without tubal cytomegalovirus infection

Bassem Refaat, Ahmed M Ashshi, Sarah A Batwa

P15 Phenotypic and genetic profiling of avian pathogenic and human diarrhegenic Escherichia coli in Egypt

Hazem Ramadan, Amal Awad, Ahmed Ateya

P16 Cancer-targeting dual gene virotherapy as a promising therapeutic strategy for treatment of hepatocellular carcinoma

Adel Galal Ahmed El-Shemi, Ahmad Ashshi, Mohammed Basalamah, Youjin Na, Chae-Ok YUN

P17 Cancer dual gene therapy with oncolytic adenoviruses expressing TRAIL and IL-12 transgenes markedly eradicated human hepatocellular carcinoma both in vitro and in vivo

Adel Galal Ahmed El-Shemi, Ahmad Ashshi, Mohammed Basalamah, Youjin Na, Chae-Ok Yun

P18 Therapy with paricalcitol attenuates tumor growth and augments tumoricidal and anti-oncogenic effects of 5-fluorouracil on animal model of colon cancer

Adel Galal El-Shemi, Bassem Refaat, Osama Kensara, Amr Abdelfattah

P19 The effects of Rubus idaeus extract on normal human lymphocytes and cancer cell line

Batol Imran Dheeb, Mohammed M. F. Al-Halbosiy, Rghad Kadhim Al lihabi, Basim Mohammed Khashman

P20 Etanercept, a TNF-alpha inhibitor, alleviates mechanical hypersensitivity and spontaneous pain in a rat model of chemotherapy-induced neuropathic pain

Djouhri, Laiche, Chaudhary Adeel, Nedjadi, Taoufik

P21 Sleeping beauty mutagenesis system identified genes and neuronal transcription factor network involved in pediatric solid tumour (medulloblastoma)

Hani Al-Afghani, Maria Łastowska, Haya H Al-Balool, Harsh Sheth, Emma Mercer, Jonathan M Coxhead, Chris PF Redfern, Heiko Peters, Alastair D Burt, Mauro Santibanez-Koref, Chris M Bacon, Louis Chesler, Alistair G Rust, David J Adams, Daniel Williamson, Steven C Clifford, Michael S Jackson

P22 Involvement of interleukin-1 in vitiligo pathogenesis

Mala Singh, Mohmmad Shoab Mansuri, Shahnawaz D. Jadeja, Hima Patel, Yogesh S. Marfatia, Rasheedunnisa Begum

P23 Cytogenetics abnormalities in 12,884 referred population for chromosomal analysis and the role of FISH in refining the diagnosis (cytogenetic experience 2004-2013)

Amal M Mohamed, Alaa K Kamel, Nivin A Helmy, Sayda A Hammad, Hesham F Kayed, Marwa I Shehab, Assad El Gerzawy, Maha M. Ead, Ola M Ead, Mona Mekkawy, Innas Mazen, Mona El-Ruby

P24 Analysis of binding properties of angiotensin-converting enzyme 2 through in silico method

S. M. A. Shahid, Qazi Mohammad Sajid Jamal, J. M. Arif, Mohtashim Lohani

P25 Relationship of genetics markers cis and trans to the β-S globin gene with fetal hemoglobin expression in Tunisian sickle cell patients

Moumni Imen, Chaouch Leila, Ouragini Houyem, Douzi Kais, Chaouachi Dorra Mellouli Fethi, Bejaoui Mohamed, Abbes Salem

P26 Analysis of estrogen receptor alpha gene polymorphisms in breast cancer: link to genetic predisposition in Sudanese women

Areeg Faggad, Amanuel T Gebreslasie, Hani Y Zaki, Badreldin E Abdalla

P27 KCNQI gene polymorphism and its association with CVD and T2DM in the Saudi population

Maha S AlShammari, Rhaya Al-Ali, Nader Al-Balawi , Mansour Al-Enazi, Ali Al-Muraikhi, Fadi Busaleh, Ali Al-Sahwan, Francis Borgio, Abdulazeez Sayyed, Amein Al-Ali, Sadananda Acharya

P28 Clinical, neuroimaging and cytogenetic study of a patient with microcephaly capillary malformation syndrome

Maha S. Zaki, Hala T. El-Bassyouni, Marwa I. Shehab

P29 Altered expression of CD200R1 on dendritic cells of patients with inflammatory bowel diseases: in silico investigations and clinical evaluations

Mohammed F. Elshal, Kaleemuddin M., Alia M. Aldahlawi, Omar Saadah,

J. Philip McCoy

P30 Development of real time PCR diagnostic protocol specific for the Saudi Arabian H1N1 viral strains

Adel E El-Tarras, Nabil S Awad, Abdulla A Alharthi, Mohamed M M Ibrahim

P31 Identification of novel genetic variations affecting Osteoarthritis patients

Haneen S Alsehli, Ashraf Dallol, Abdullah M Gari, Mohammed M Abbas, Roaa A Kadam, Mazen M. Gari, Mohmmed H Alkaff, Adel M Abuzenadah, Mamdooh A Gari

P32 An integrated database of GWAS SNVs and their evolutionary properties

Heba Abusamra, Sajjad Karim, Hend F Nour eldin, Elham M Alhathli, Nada Salem, Sudhir Kumar, Mohammed H Al-Qahtani

P33 Familial hypercholesterolemia in Saudi Arabia: prime time for a national registry and genetic analysis

Fatima A. Moradi, Omran M. Rashidi, Zuhier A. Awan

P34 Comparative genomics and network-based analyses of early hepatocellular carcinoma

Ibrahim Hamza Kaya, Olfat Al-Harazi, Dilek Colak

P35 A TALEN-based oncolytic viral vector approach to knock out ABCB1 gene mediated chemoresistance in cancer stem cells

Nabila A Alkousi, Takis Athanasopoulos

P36 Cartilage differentiation and gene expression of synovial fluid mesenchymal stem cells derived from osteoarthritis patients

Afnan O Bahmaid, Etimad A Alhwait, Mamdooh A Gari, Haneen S Alsehli, Mohammed M Abbas, Mohammed H Alkaf, Roaa Kadam, Ashraf Dallol, Gauthaman Kalamegam

P37 E-GRASP: Adding an evolutionary component to the genome-wide repository of associations (GRASP) resource

Hend F Nour Eldin, Sajjad Karim, Heba Abusamra, Elham Alhathli, Nada Salem, Mohammed H Al-Qahtani, Sudhir Kumar

P38 Screening of AGL gene mutation in Saudi family with glycogen storage disease Type III

Salma N Alsayed, Fawziah H Aljohani, Samaher M Habeeb, Rawan A Almashali, Sulman Basit, Samia M Ahmed

P39 High throughput proteomic data suggest modulation of cAMP dependent protein kinase A and mitochondrial function in infertile patients with varicocele

Rakesh Sharma, Ashok Agarwal, Damayanthi Durairajanayagam, Luna Samanta, Muhammad Abu-Elmagd, Adel M. Abuzenadah, Edmund S. Sabanegh, Mourad Assidi, Mohammed Al-Qahtani

P40 Significant protein profile alterations in men with primary and secondary infertility

Ashok Agarwal, Rakesh Sharma, Luna Samanta, Damayanthi Durairajanayagam, Mourad Assidi, Muhammad Abu-Elmagd, Mohammed Al-Qahtani, Adel M. Abuzenadah, Edmund S. Sabanegh

P41 Spermatozoa maturation in infertile patients involves compromised expression of heat shock proteins

Luna Samanta, Ashok Agarwal, Rakesh Sharma, Zhihong Cui, Mourad Assidi, Adel M. Abuzenadah, Muhammad Abu-Elmagd, Mohammed Al-Qahtani

P42 Array comparative genomic hybridization approach to search genomic answers for spontaneous recurrent abortion in Saudi Arabia

Alaa A Alboogmi, Nuha A Alansari, Maha M Al-Quaiti, Fai T Ashgan, Afnan Bandah, Hasan S Jamal, Abdullraheem Rozi_, Zeenat Mirza, Adel M Abuzenadah, Sajjad Karim, Mohammed H Al-Qahtani

P43 Global gene expression profiling of Saudi kidney cancer patients

Sajjad Karim, Hans-Juergen Schulten, Ahmad J Al Sayyad, Hasan MA Farsi, Jaudah A Al-Maghrabi, Zeenat Mirza, Reem Alotibi, Alaa Al-Ahmadi, Nuha A Alansari, Alaa A Albogmi, Maha M Al-Quaiti, Fai T Ashgan, Afnan Bandah, Mohammed H Al-Qahtani

P44 Downregulated StAR gene and male reproductive dysfunction caused by nifedipine and ethosuximide

Rasha A Ebiya, Samia M Darwish, Metwally M. Montaser

P45 Clustering based gene expression feature selection method: A computational approach to enrich the classifier efficiency of differentially expressed genes

Heba Abusamra, Vladimir B. Bajic

P46 Prognostic significance of Osteopontin expression profile in colorectal carcinoma

Jaudah Al-Maghrabi, Wafaey Gomaa, Mehenaz Hanbazazh, Mahmoud Al-Ahwal, Asia Al-Harbi, Wejdan Al-Qahtani, Saher Hakamy, Ghali Baba, Abdelbaset Buhmeida, Mohammed Al-Qahtani

P47 High Glypican-3 expression pattern predicts longer disease-specific survival in colorectal carcinoma

Jaudah Al-Maghrabi, Abdullah Al-Harbi, Mahmoud Al-Ahwal, Asia Al-Harbi, Wejdan Al-Qahtani, Sahar Hakamy, Ghalia Baba, Abdelbaset Buhmeida, Mohammed Al-Qahtani

P48 An evolutionary re-assessment of GWAS single nucleotide variants implicated in the Cholesterol traits

Elham M Alhathli, Sajjad Karim, Nada Salem, Hend Nour Eldin, Heba Abusamra, Sudhir Kumar, Mohammed H Al-Qahtani

P49 Derivation and characterization of human Wharton’s jelly stem cells (hWJSCs) in vitro for future therapeutic applications

Aisha A Alyamani, Gauthaman Kalamegam, Etimad A Alhwait, Mamdooh A Gari, Mohammed M Abbas, Mohammed H Alkaf, Haneen S Alsehli, Roaa A Kadam, Mohammed Al-Qahtani

P50 Attitudes of healthcare students toward biomedical research in the post-genomic era

Rawan Gadi, Abdelbaset Buhmeida, Mourad Assidi , Adeel Chaudhary, Leena Merdad

P51 Evaluation of the immunomodulatory effects of thymoquinone on human bone marrow mesenchymal stem cells (BM-MSCs) from osteoarthritic patients

Saadiah M Alfakeeh, Etimad A Alhwait, Mamdooh A Gari, Mohammed M Abbas, Mohammed H Alkaf, Haneen S Alsehli, Roaa Kadam, Gauthaman Kalamegam

P52 Implication of IL-10 and IL-28 polymorphism with successful anti-HCV therapy and viral clearance

Rubi Ghazala, Shilu Mathew, M.Haroon Hamed, Mourad Assidi, Mohammed Al-Qahtani, Ishtiaq Qadri

P53 Selection of flavonoids against obesity protein (FTO) using in silico and in vitro approaches

Shilu Mathew, Lobna Mira, Manal Shaabad, Shireen Hussain, Mourad Assidi, Muhammad Abu-Elmagd, Mohammed Al-Qahtani

P54 Computational selection and in vitro validation of flavonoids as new antidepressant agents

Shilu Mathew, Manal Shaabad, Lobna Mira, Shireen Hussain, Mourad Assidi, Muhammad Abu-Elmagd, Mohammed Al-Qahtani

P55 In Silico prediction and prioritization of aging candidate genes associated with

progressive telomere shortening

Ahmed Rebai, Mourad Assidi, Abdelbaset Buhmeida, Muhammad Abu-Elmagd, Ashraf Dallol, Jerry W Shay

P56 Identification of new cancer testis antigen genes in diverse types of malignant human tumour cells

Mikhlid H Almutairi

P57 More comprehensive forensic genetic marker analyses for accurate human remains identification using massively parallel sequencing (MPS)

Angie Ambers, Jennifer Churchill, Jonathan King, Monika Stoljarova, Harrell Gill-King, Mourad Assidi, Muhammad Abu-Elmagd, Abdelbaset Buhmeida, Muhammad Al-Qatani, Bruce Budowle

P58 Flow cytometry approach towards treatment men infertility in Saudi Arabia

Muhammad Abu-Elmagd, Farid Ahmed, Ashraf Dallol, Mourad Assidi, Taha Abo Almagd, Sahar Hakamy, Ashok Agarwal, Muhammad Al-Qahtani, Adel Abuzenadah

P59 Tissue microarray based validation of CyclinD1 expression in renal cell carcinoma of Saudi kidney patients

Sajjad Karim, Hans-Juergen Schulten, Ahmad J Al Sayyad, Hasan MA Farsi, Jaudah A Al-Maghrabi, Abdelbaset Buhmaida, Zeenat Mirza, Reem Alotibi, Alaa Al-Ahmadi, Nuha A Alansari, Alaa A Albogmi, Maha M Al-Quaiti, Fai T Ashgan, Afnan Bandah, Mohammed H Al-Qahtani

P60 Assessment of gold nanoparticles in molecular diagnostics and DNA damage studies

Rukhsana Satar, Mahmood Rasool, Waseem Ahmad, Nazia Nazam, Mohamad I Lone, Muhammad I Naseer, Mohammad S Jamal, Syed K Zaidi, Peter N Pushparaj, Mohammad A Jafri, Shakeel A Ansari, Mohammed H Alqahtani

P61 Surfing the biospecimen management and processing workflow at CEGMR Biobank

Hanan Bashier, Abrar Al Qahtani, Shilu Mathew, Amal M. Nour, Heba Alkhatabi, Adel M. Abu Zenadah, Abdelbaset Buhmeida, Mourad Assidi, Muhammed Al Qahtani

P62 Autism Spectrum Disorder: knowledge, attitude and awareness in Jeddah, Kingdom of Saudi Arabia

Muhammad Faheem, Shilu Mathew, Shiny Mathew, Peter Natesan Pushparaj, Mohammad H. Al-Qahtani

P63 Simultaneous genetic screening of the coagulation pathway genes using the Thromboscan targeted sequencing panel

Hani A. Alhadrami, Ashraf Dallol, Adel Abuzenadah

P64 Genome wide array comparative genomic hybridization analysis in patients with syndromic congenital heart defects

Ibtessam R. Hussein, Adeel G. Chaudhary, Rima S Bader, Randa Bassiouni, Maha Alquaiti, Fai Ashgan, Hans Schulten, Mohamed Nabil Alama, Mohammad H. Al Qahtani

P65 Toxocogenetic evaluation of 1, 2-Dichloroethane in bone marrow, blood and cells of immune system using conventional, molecular and flowcytometric approaches

Mohammad I Lone, Nazia Nizam, Waseem Ahmad, Mohammad A Jafri, Mahmood Rasool, Shakeel A Ansari, Muhammed H Al-Qahtani

P66 Molecular cytogenetic diagnosis of sexual development disorders in newborn: A case of ambiguous genitalia

Eradah Alshihri, Muhammad Abu-Elmagd, Lina Alharbi, Mourad Assidi, Mohammed Al-Qahtani

P67 Identification of disease specific gene expression clusters and pathways in hepatocellular carcinoma using In Silico methodologies

Shilu Mathew, Peter Pushparaj Natesan, Muhammed Al Qahtani

P68 Human Wharton’s Jelly stem cell conditioned medium inhibits primary ovarian cancer cells in vitro: Identification of probable targets and mechanisms using systems biology

Gauthaman Kalamegam, Peter Natesan Pushparaj, Fazal Khan, Roaa Kadam, Farid Ahmed, Mourad Assidi, Khalid Hussain Wali Sait, Nisreen Anfinan, Mohammed Al Qahtani

P69 Mutation spectrum of ASPM (Abnormal Spindle-like, Microcephaly-associated) gene in Saudi Arabian population

Muhammad I Naseer, Adeel G Chaudhary, Mohammad S Jamal, Shilu Mathew, Lobna S Mira, Peter N Pushparaj, Shakeel A Ansari, Mahmood Rasool, Mohammed H AlQahtani

P70 Identification and characterization of novel genes and mutations of primary microcephaly in Saudi Arabian population

Muhammad I Naseer, Adeel G Chaudhary, Shilu Mathew, Lobna S Mira, Mohammad S Jamal, Sameera Sogaty, Randa I Bassiouni, Mahmood Rasool, Mohammed H AlQahtani

P71 Molecular genetic analysis of hereditary nonpolyposis colorectal cancer (Lynch Syndrome) in Saudi Arabian population

Mahmood Rasool, Shakeel A Ansari, Mohammad S Jamal, Peter N Pushparaj, Abdulrahman MS Sibiani, Waseem Ahmad, Abdelbaset Buhmeida, Mohammad A Jafri, Mohiuddin K Warsi, Muhammad I Naseer, Mohammed H Al-Qahtani

P72 Function predication of hypothetical proteins from genome database of chlamydia trachomatis

Rubi, Kundan Kumar, Ahmad AT Naqvi, Faizan Ahmad, Md I Hassan, Mohammad S Jamal, Mahmood Rasool, Mohammed H AlQahtani

P73 Transcription factors as novel molecular targets for skin cancer

Ashraf Ali, Jummanah Jarullah, Mahmood Rasool, Abdelbasit Buhmeida, Shahida Khan, Ghufrana Abdussami, Maryam Mahfooz, Mohammad A Kamal, Ghazi A Damanhouri, Mohammad S Jamal

P74 An In Silico analysis of Plumbagin binding to apoptosis executioner: Caspase-3 and Caspase-7

Bushra Jarullah, Jummanah Jarullah, Mohammad SS Jarullah, Ashraf Ali, Mahmood Rasool, Mohammad S Jamal

P75 Single cell genomics applications for preimplantation genetic screening optimization: Comparative analysis of whole genome amplification technologies

Mourad Assidi, Muhammad Abu-Elmagd, Osama Bajouh, Peter Natesan Pushparaj, Mohammed Al-Qahtani, Adel Abuzenadah

P76 ZFP36 regulates miRs-34a in anti-IgM triggered immature B cells

Mohammad S Jamal, Jummanah Jarullah, Abdulah EA Mathkoor, Hashim MA Alsalmi, Anas MM Oun, Ghazi A Damanhauri, Mahmood Rasool, Mohammed H AlQahtani

P77 Identification of a novel mutation in the STAMBP gene in a family with microcephaly-capillary malformation syndrome

Muhammad I. Naseer, Mahmood Rasool, Sameera Sogaty, Adeel G. Chudhary, Yousif A. Abutalib, Daniele Merico, Susan Walker, Christian R. Marshall, Mehdi Zarrei, Stephen W. Scherer, Mohammad H. Al-Qahtani

P78 Copy number variations in Saudi patients with intellectual disability and epilepsy

Muhammad I. Naseer, Muhammad Faheem, Adeel G. Chaudhary, Mahmood Rasool, Gauthaman Kalamegam, Fai Talal Ashgan, Mourad Assidi, Farid Ahmed, Syed Kashif Zaidi, Mohammed M. Jan, Mohammad H. Al-Qahtani

P79 Prognostic significance of CD44 expression profile in colorectal carcinoma

Maryam Al-Zahrani, Sahira Lary, Sahar Hakamy, Ashraf Dallol, Mahmoud Al-Ahwal, Jaudah Al-Maghrabi, Emmanuel Dermitzakis, Adel Abuzenadah, Abdelbaset Buhmeida, Mohammed Al-Qahtani

P80 Association of the endothelial nitric oxide synthase (eNOS) gene G894T polymorphism with hypertension risk and complications

Abeer A Al-refai, Mona Saleh, Rehab I Yassien, Mahmmoud Kamel, Rabab M Habeb

P81 SNPs array to screen genetic variation among diabetic patients

Najlaa Filimban, Ashraf Dallol, Nadia Ghannam, Mohammed Al-Qahtani, Adel Mohammed Abuzenadah

P82 Detection and genotyping of Helicobacter pylori among gastric cancer patients from Saudi Arabian population

Fehmida Bibi, Sana Akhtar, Esam I. Azhar, Muhammad Yasir, Muhammad I. Nasser, Asif A. Jiman-Fatani, Ali Sawan

P83 Antimicrobial drug resistance and molecular detection of susceptibility to Fluoroquinolones among clinical isolates of Salmonella species from Jeddah-Saudi Arabia

Ruaa A Lahzah, Asho Ali

P84 Identification of the toxic and virulence nature of MAP1138c protein of Mycobacterium avium subsp. paratuberculosis

Syed A Hassan, Seyed E Hasnain, Iftikhar A Tayubi, Hamza A Abujabal, Alaa O Magrabi

P85 In vitro and in silico evaluation of miR137 in human breast cancer

Fazal Khan, Gauthaman Kalamegam, Peter Natesan Pushparaj, Adel Abuzenada, Taha Abduallah Kumosani, Elie Barbour, Mohammed Al-Qahtani

P86 Auruka gene is over-expressed in Saudi breast cancer

Manal Shabaad, Shilu Mathew, Ashraf Dallol, Adnan Merdad, Abdelbaset Buhmeida, Mohammed Al-Qahtani

P87 The potential of immunogenomics in personalized healthcare

Mourad Assidi, Muhammad Abu-Elmagd, Kalamegam Gauthaman, Mamdooh Gari, Adeel Chaudhary, Adel Abuzenadah, Peter Natesan Pushparaj, Mohammed Al-Qahtani

P88 In Silico physiochemical and structural characterization of a putative ORF MAP0591 and its implication in the pathogenesis of Mycobacterium paratuberculosis in ruminants and humans

Syed A Hassan, Iftikhar A Tayubi, Hani MA Aljahdali

P89 Effects of heat shock on human bone marrow mesenchymal stem cells (BM-MSCs): Implications in regenerative medicine

Reham Al Nono, Mamdooh Gari, Haneen Alsehli, Farid Ahmed, Mohammed Abbas, Gauthaman Kalamegam, Mohammed Al-Qahtani

P90 In Silico analyses of the molecular targets of Resveratrol unravels its importance in mast cell mediated allergic responses

Shilu Mathew, Fazal Khan, Mahmood Rasool, Mohammed Sarwar Jamal, Muhammad Imran Naseer, Zeenat Mirza, Sajjad Karim, Shakeel Ansari, Mourad Assidi, Gauthaman Kalamegam, Mamdooh Gari, Adeel Chaudhary, Adel Abuzenadah, Peter Natesan Pushparaj, Mohammed Al-Qahtani

P91 Effects of environmental particulate matter on bone-marrow mesenchymal stem cells

Muhammad Abu-Elmagd, Gauthaman Kalamegam, Roaa Kadam, Mansour A Alghamdi, Magdy Shamy, Max Costa, Mamdouh I Khoder, Mourad Assidi, Peter Natesan Pushparaj, Mamdooh Gari, Mohammed Al-Qahtani

P92 Distinctive charge clusters in human virus proteomes

Najla Kharrat, Sabrine Belmabrouk, Rania Abdelhedi, Riadh Benmarzoug, Mourad Assidi, Mohammed H. Al Qahtani, Ahmed Rebai

P93 In vitro experimental model and approach in identification of new biomarkers of inflammatory forms of arthritis

Ghazi Dhamanhouri, Peter Natesan Pushparaj, Abdelwahab Noorwali, Mohammad Khalid Alwasiyah, Afnan Bahamaid, Saadiah Alfakeeh, Aisha Alyamani, Haneen Alsehli, Mohammed Abbas, Mamdooh Gari, Ali Mobasheri, Gauthaman Kalamegam, Mohammed Al-Qahtani

P94 Molecular docking of GABA_A receptor subunit γ-2 with novel anti-epileptic compounds

Muhammad Faheem, Shilu Mathew, Peter Natesan Pushparaj, Mohammad H. Al-Qahtani

P95 Breast cancer knowledge, awareness, and practices among Saudi females residing in Jeddah

Shilu Mathew, Muhammad Faheem, Shiny Mathew, Peter Natesan Pushparaj, Mohammad H. Al-Qahtani

P96 Anti-inflammatory role of Sesamin by Attenuation of Iba1/TNF-α/ICAM-1/iNOS signaling in Diabetic Retinopathy

Mohammad Sarwar Jamal, Syed Kashif Zaidi, Raziuddin Khan, Kanchan Bhatia, Mohammed H. Al-Qahtani, Saif Ahmad

P97 Identification of drug lead molecule against vp35 protein of Ebola virus: An In-Silico approach

Iftikhar AslamTayubi, Manish Tripathi, Syed Asif Hassan, Rahul Shrivastava

P98 An approach to personalized medicine from SNP-calling through disease analysis using whole exome-sequencing of three sub-continental populations

Iftikhar A Tayubi, Syed Hassan, Hamza A.S Abujabal

P99 Low versus high frequency of Glucose –6 – Phosphate Dehydrogenase (G6PD) deficiency in urban against tribal population of Gujarat – A signal to natural selection

Ishani Shah, Bushra Jarullah, Mohammad S Jamal, Jummanah Jarullah

P100 Spontaneous preterm birth and single nucleotide gene polymorphisms: a recent update

Ishfaq A Sheikh, Ejaz Ahmad, Mohammad S Jamal, Mohd Rehan, Muhammad Abu-Elmagd, Iftikhar A Tayubi, Samera F AlBasri, Osama S Bajouh, Rola F Turki, Adel M Abuzenadah, Ghazi A Damanhouri, Mohd A Beg, Mohammed Al-Qahtani

P101 Prevalence of congenital heart diseases among Down syndrome cases in Saudi Arabia: role of molecular genetics in the pathogenesis

Sahar AF Hammoudah, Khalid M AlHarbi, Lama M El-Attar, Ahmed MZ Darwish

P102 Combinatorial efficacy of specific pathway inhibitors in breast cancer cells

Sara M Ibrahim, Ashraf Dallol_, Hani Choudhry, Adel Abuzenadah, Jalaludden Awlia, Adeel Chaudhary, Farid Ahmed, Mohammed Al-Qahtani

P103 MiR-143 and miR-145 cluster as potential replacement medicine for the treatment of cancer

Mohammad A Jafri, Muhammad Abu-Elmagd, Mourad Assidi, Mohammed Al-Qahtani

P104 Metagenomic profile of gut microbiota during pregnancy in Saudi population

Imran khan, Muhammad Yasir, Esam I. Azhar, Sameera Al-basri, Elie Barbour, Taha Kumosani

P105 Exploration of anticancer targets of selected metabolites of Phoenix dactylifera L. using systems biological approaches

Fazal Khan, Gauthaman Kalamegam, Peter Natesan Pushparaj, Adel Abuzenada, Taha Abduallah Kumosani, Elie Barbour

P106 CD226 and CD40 gene polymorphism in susceptibility to Juvenile rheumatoid arthritis in Egyptian patients

Heba M. EL Sayed, Eman A. Hafez

P107 Paediatric exome sequencing in autism spectrum disorder ascertained in Saudi families

Hans-Juergen Schulten, Aisha Hassan Elaimi, Ibtessam R Hussein, Randa Ibrahim Bassiouni, Mohammad Khalid Alwasiyah, Richard F Wintle, Adeel Chaudhary, Stephen W Scherer, Mohammed Al-Qahtani

P108 Crystal structure of the complex formed between Phospholipase A₂ and the central core hydrophobic fragment of Alzheimer’s β- amyloid peptide: a reductionist approach

Zeenat Mirza, Vikram Gopalakrishna Pillai, Sajjad Karim, Sujata Sharma, Punit Kaur, Alagiri Srinivasan, Tej P Singh, Mohammed Al-Qahtani

P109 Differential expression profiling between meningiomas from female and male patients

Reem Alotibi, Alaa Al-Ahmadi, Fatima Al-Adwani, Deema Hussein, Sajjad Karim, Mona Al-Sharif, Awatif Jamal, Fahad Al-Ghamdi, Jaudah Al-Maghrabi, Saleh S Baeesa, Mohammed Bangash, Adeel Chaudhary, Hans-Juergen Schulten, Mohammed Al-Qahtani

P110 Neurospheres as models of early brain development and therapeutics

Muhammad Faheem, Peter Natesan Pushparaj, Shilu Mathew, Taha Abdullah Kumosani, Gauthaman Kalamegam, Mohammed Al-Qahtani

P111 Identification of a recurrent causative missense mutation p.(W577C) at the LDLR exon 12 in familial hypercholesterolemia affected Saudi families

Faisal A Al-Allaf, Zainularifeen Abduljaleel, Abdullah Alashwal, Mohiuddin M. Taher, Abdellatif Bouazzaoui, Halah Abalkhail, Faisal A. Ba-Hammam, Mohammad Athar

P112 Epithelial ovarian carcinoma (EOC): Systems oncological approach to identify diagnostic, prognostic and therapeutic biomarkers

Gauthaman Kalamegam, Peter Natesan Pushparaj, Muhammad Abu-Elmagd, Farid Ahmed Khalid HussainWali Sait, Nisreen Anfinan, Mamdooh Gari, Adeel Chaudhary, Adel Abuzenadah, Mourad Assidi, Mohammed Al-Qahtani

P113 Crohn’s disease phenotype in northern Tunisian population

Naira Ben Mami, Yosr Z Haffani, Mouna Medhioub, Lamine Hamzaoui, Ameur Cherif, Msadok Azouz

P114 Establishment of In Silico approaches to decipher the potential toxicity and mechanism of action of drug candidates and environmental agents

Gauthaman Kalamegam, Fazal Khan, Shilu Mathew, Mohammed Imran Nasser, Mahmood Rasool, Farid Ahmed, Peter Natesan Pushparaj, Mohammed Al-Qahtani

P115 1q Gain predicts poor prognosis marker for young breast cancer patients

Shereen A Turkistany, Lina M Al-harbi, Ashraf Dallol, Jamal Sabir, Adeel Chaudhary, Adel Abuzenadah

P116 Disorders of sex chromosomes in a diagnostic genomic medicine unit in Saudi Arabia: Prevalence, diagnosis and future guidelines

Basmah Al-Madoudi, Bayan Al-Aslani, Khulud Al-Harbi, Rwan Al-Jahdali, Hanadi Qudaih, Emad Al Hamzy, Mourad Assidi, Mohammed Al Qahtani

P117 Combination of WYE354 and Sunitinib demonstrate synergistic inhibition of acute myeloid leukemia in vitro

Asad M Ilyas, Youssri Ahmed, Mamdooh Gari, Farid Ahmed, Mohammed Alqahtani

P118 Integrated use of evolutionary information in GWAS reveals important SNPs in Asthma

Nada Salem, Sajjad Karim, Elham M Alhathli, Heba Abusamra, Hend F Nour Eldin, Mohammed H Al-Qahtani, Sudhir Kumar

P119 Assessment of BRAF, IDH1, IDH2, and EGFR mutations in a series of primary brain tumors

Fatima Al-Adwani, Deema Hussein, Mona Al-Sharif, Awatif Jamal, Fahad Al-Ghamdi, Jaudah Al-Maghrabi, Saleh S Baeesa, Mohammed Bangash, Adeel Chaudhary, Mohammed Al-Qahtani, Hans-Juergen Schulten

P120 Expression profiles distinguish oligodendrogliomas from glioblastoma multiformes with or without oligodendroglioma component

Alaa Alamandi, Reem Alotibi, Deema Hussein, Sajjad Karim, Jaudah Al-Maghrabi, Fahad Al-Ghamdi, Awatif Jamal, Saleh S Baeesa, Mohammed Bangash, Adeel Chaudhary, Hans-Juergen Schulten, Mohammed Al-Qahtani

P121 Hierarchical clustering in thyroid goiters and hyperplastic lesions

Ohoud Subhi, Nadia Bagatian, Sajjad Karim, Adel Al-Johari, Osman Abdel Al-Hamour, Hosam Al-Aradati, Abdulmonem Al-Mutawa, Faisal Al-Mashat, Jaudah Al-Maghrabi, Hans-Juergen Schulten, Mohammad Al-Qahtani

P122 Differential expression analysis in thyroiditis and papillary thyroid carcinomas with or without coexisting thyroiditis

Nadia Bagatian, Ohoud Subhi, Sajjad Karim, Adel Al-Johari, Osman Abdel Al-Hamour, Abdulmonem Al-Mutawa, Hosam Al-Aradati, Faisal Al-Mashat, Mohammad Al-Qahtani, Hans-Juergen Schulten, Jaudah Al-Maghrabi

P123 Metagenomic analysis of waste water microbiome in Sausdi Arabia

Muhammad W shah, Muhammad Yasir, Esam I Azhar, Saad Al-Masoodi

P124 Molecular characterization of Helicobacter pylori from faecal samples of Tunisian patients with gastric cancer

Yosr Z Haffani, Msadok Azouz, Emna Khamla, Chaima Jlassi, Ahmed S. Masmoudi, Ameur Cherif, Lassaad Belbahri

P125 Diagnostic application of the oncoscan^© panel for the identification of hereditary cancer syndrome

Shadi Al-Khayyat, Roba Attas, Atlal Abu-Sanad, Mohammed Abuzinadah, Adnan MerdadAshraf Dallol, Adeel Chaudhary, Mohammed Al-Qahtani, Adel Abuzenadah

P126 Characterization of clinical and neurocognitive features in a family with a novel OGT gene missense mutation c. 1193G > A/ (p. Ala319Thr)

Habib Bouazzi, Carlos Trujillo, Mohammad Khalid Alwasiyah, Mohammed Al-Qahtani

P127 Case report: a rare homozygous deletion mutation of TMEM70 gene associated with 3-Methylglutaconic Aciduria and cataract in a Saudi patient

Maha Alotaibi, Rami Nassir

P128 Isolation and purification of antimicrobial milk proteins

Ishfaq A Sheikh, Mohammad A Kamal, Essam H Jiffri, Ghulam M Ashraf, Mohd A Beg

P129 Integrated analysis reveals association of ATP8B1 gene with colorectal cancer

Mohammad A Aziz, Rizwan Ali, Mahmood Rasool, Mohammad S Jamal, Nusaibah samman, Ghufrana Abdussami, Sathish Periyasamy, Mohiuddin K Warsi, Mohammed Aldress, Majed Al Otaibi, Zeyad Al Yousef, Mohamed Boudjelal, Abdelbasit Buhmeida, Mohammed H Al-Qahtani, Ibrahim AlAbdulkarim

P130 Implication of IL-10 and IL-28 polymorphism with successful anti-HCV therapy and viral clearance

Rubi Ghazala, Shilu Mathew, M. Haroon Hamed, Mourad Assidi, Mohammed Al-Qahtani, Ishtiaq Qadri

P131 Interactions of endocrine disruptor di-(2-ethylhexyl) phthalate (DEHP) and its metabolite mono-2-ethylhexyl phthalate (MEHP) with progesterone receptor

Ishfaq A Sheikh, Muhammad Abu-Elmagd, Rola F Turki, Ghazi A Damanhouri, Mohd A. Beg

P132 Association of HCV nucleotide polymorphism in the development of hepatocellular carcinoma

Mohd Suhail, Abid Qureshi, Adil Jamal, Peter Natesan Pushparaj, Mohammad Al-Qahtani, Ishtiaq Qadri

P133 Gene expression profiling by DNA microarrays in colon cancer treated with chelidonine alkaloid

Mahmoud Z El-Readi, Safaa Y Eid, Michael Wink

P134 Successful in vitro fertilization after eight failed trials

Ahmed M. Isa, Lulu Alnuaim, Johara Almutawa, Basim Abu-Rafae, Saleh Alasiri, Saleh Binsaleh

P135 Genetic sensitivity analysis using SCGE, cell cycle and mitochondrial membrane potential in OPs stressed leukocytes in Rattus norvegicus through flow cytometric input

Nazia Nazam, Mohamad I Lone, Waseem Ahmad, Shakeel A Ansari, Mohamed H Alqahtani

Monocyte Chemoattractant Protein-Induced Protein 1 Overexpression Modulates Transcriptome, Including MicroRNA, in Human Neuroblastoma Cells

The recently discovered MCPIP1 (monocyte chemoattractant protein-induced protein 1), a multidomain protein encoded by the MCPIP1 (ZC3H12A) gene, has been described as a new differentiation factor, a ribonuclease, and a deubiquitination-supporting factor. However, its role in cancer is poorly recognized. Our recent analysis of microarrays data showed a lack of expression of the MCPIP1 transcript in primary neuroblastoma, the most common extracranial solid tumor in children. Additionally, enforced expression of the MCPIP1 gene in BE(2)-C cells caused a significant decrease in neuroblastoma proliferation and viability. Aim of the present study was to further investigate the role of MCPIP1 in neuroblastoma, using expression DNA microarrays and microRNA microarrays. Transient transfections of BE(2)-C cells were used for overexpression of either wild type of MCPIP1 (MCPIP1-wt) or its RN-ase defective mutant (MCPIP1-ΔPIN). We have analyzed changes of transcriptome and next, we have used qRT-PCR to verify mRNA levels of selected genes responding to MCPIP1 overexpression. Additionally, protein levels were determined for some of the selected genes. The choline transporter, CTL1, encoded by the SLC44A1 gene, was significantly repressed at the specific mRNA and protein levels and most importantly this translated into a decreased choline transport in MCPIP1-overexpressing cells. Then, we have found microRNA-3613-3p as the mostly altered in the pools of cells overexpressing the wild type MCPIP1. Next, we analyzed the predicted targets of the miR-3613-3p and validated them using qRT-PCR and western blot. These results indicate that the expression of miR-3613-3p might be regulated by MCPIP1 by cleavage of its precursor form.

Contrast enhancement pattern predicts poor survival for patients with non-WNT/SHH medulloblastoma tumours

Recent studies revealed the biological heterogeneity of medulloblastoma, with the existence of at least four groups which are associated with several clinical and morphological features. We investigated for further correlations between molecular types, location of tumours, their contrast enhancement pattern and survival of patients. Altogether 76 tumours were analyzed and molecular subtypes were identified by immunohistochemistry using representative antibodies, detection of chromosome 6 monosomy and CTNNB1 mutation. The site of the tumour was assessed on diagnosis using Magnetic Resonance images and intra-operative surgical reports. In addition, the gadolinium enhancement pattern was also investigated in pre-treatment tumours. Cerebellar hemispheric location was associated with SHH tumours (p < 0.001), as opposed to midline location being typical for WNT and non-WNT/SHH tumours. Remarkably, for patients with non-WNT/SHH tumours, the extensive gadolinium enhancement pattern (present in >75% of tumour volume) predicted worse OS and EFS than for those with none/weak or heterogeneous enhancement (>10-75% of tumour volume), (both p < 0.001). Our analysis indicates that distribution of the medulloblastoma tumours location is related to the biological characteristics of tumour. Importantly, the enhancement pattern of the tumour may be a clinically useful prognostic marker for patients with non-WNT/SHH medulloblastomas.

Identification of a neuronal transcription factor network involved in medulloblastoma development

BACKGROUND

Medulloblastomas, the most frequent malignant brain tumours affecting children, comprise at least 4 distinct clinicogenetic subgroups. Aberrant sonic hedgehog (SHH) signalling is observed in approximately 25% of tumours and defines one subgroup. Although alterations in SHH pathway genes (e.g. PTCH1, SUFU) are observed in many of these tumours, high throughput genomic analyses have identified few other recurring mutations. Here, we have mutagenised the Ptch+/- murine tumour model using the Sleeping Beauty transposon system to identify additional genes and pathways involved in SHH subgroup medulloblastoma development.

RESULTS

Mutagenesis significantly increased medulloblastoma frequency and identified 17 candidate cancer genes, including orthologs of genes somatically mutated (PTEN, CREBBP) or associated with poor outcome (PTEN, MYT1L) in the human disease. Strikingly, these candidate genes were enriched for transcription factors (p=2x10-5), the majority of which (6/7; Crebbp, Myt1L, Nfia, Nfib, Tead1 and Tgif2) were linked within a single regulatory network enriched for genes associated with a differentiated neuronal phenotype. Furthermore, activity of this network varied significantly between the human subgroups, was associated with metastatic disease, and predicted poor survival specifically within the SHH subgroup of tumours. Igf2, previously implicated in medulloblastoma, was the most differentially expressed gene in murine tumours with network perturbation, and network activity in both mouse and human tumours was characterised by enrichment for multiple gene-sets indicating increased cell proliferation, IGF signalling, MYC target upregulation, and decreased neuronal differentiation.

CONCLUSIONS

Collectively, our data support a model of medulloblastoma development in SB-mutagenised Ptch+/- mice which involves disruption of a novel transcription factor network leading to Igf2 upregulation, proliferation of GNPs, and tumour formation. Moreover, our results identify rational therapeutic targets for SHH subgroup tumours, alongside prognostic biomarkers for the identification of poor-risk SHH patients.

Identification of candidate genes involved in neuroblastoma progression by combining genomic and expression microarrays with survival data

Identifying genes, whose expression is consistently altered by chromosomal gains or losses, is an important step in defining genes of biological relevance in a wide variety of tumour types. However, additional criteria are needed to discriminate further among the large number of candidate genes identified. This is particularly true for neuroblastoma, where multiple genomic copy number changes of proven prognostic value exist. We have used Affymetrix microarrays and a combination of fluorescent in situ hybridization and single nucleotide polymorphism (SNP) microarrays to establish expression profiles and delineate copy number alterations in 30 primary neuroblastomas. Correlation of microarray data with patient survival and analysis of expression within rodent neuroblastoma cell lines were then used to define further genes likely to be involved in the disease process. Using this approach, we identify >1000 genes within eight recurrent genomic alterations (loss of 1p, 3p, 4p, 10q and 11q, 2p gain, 17q gain, and the MYCN amplicon) whose expression is consistently altered by copy number change. Of these, 84 correlate with patient survival, with the minimal regions of 17q gain and 4p loss being enriched significantly for such genes. These include genes involved in RNA and DNA metabolism, and apoptosis. Orthologues of all but one of these genes on 17q are overexpressed in rodent neuroblastoma cell lines. A significant excess of SNPs whose copy number correlates with survival is also observed on proximal 4p in stage 4 tumours, and we find that deletion of 4p is associated with improved outcome in an extended cohort of tumours. These results define the major impact of genomic copy number alterations upon transcription within neuroblastoma, and highlight genes on distal 17q and proximal 4p for downstream analyses. They also suggest that integration of discriminators, such as survival and comparative gene expression, with microarray data may be useful in the identification of critical genes within regions of loss or gain in many human cancers.

Regions syntenic to human 17q are gained in mouse and rat neuroblastoma

Gain of chromosome arm 17q is the most frequent chromosomal change in human neuroblastoma and is a powerful predictor of adverse outcome of disease. This suggests that the region of gain includes a gene or genes critical for tumor pathogenesis. Analyses of breakpoint positions have revealed that the shortest region of gain (SRG) extends from MPO (17q23.1) to 17qter. Because this encompasses >300 genes, it precludes the identification of candidate genes from human breakpoint data alone. However, mouse chromosome 11, which is syntenic to human chromosome 17, is gained in up to 30% of neuroblastoma tumors developed in a murine MYCN transgenic model of this disease. To confirm that this key genetic change indicates the involvement of a molecular pathway conserved between mouse and man and is not occurring coincidentally in the transgenic model, we used fluorescence in situ hybridization to analyze sporadic cases of both mouse and rat neuroblastoma. Our results confirmed the presence of chromosome 11 gain in all three of the mouse cell lines we analyzed, with the SRG extending from Stat5b (101.6 Mb) to tel. In addition, the rat neuroblastoma cell line harbors an extra copy of distal chromosome 10, extending from 92.8 to 109.3 Mb, which is also syntenic to human 17q. Comparison of the regions gained in all three species has excluded 4.2 Mb from the previously defined region of 17q gain in humans as a likely location of the candidate gene or genes, and strongly suggests that the molecular etiology of neuroblastoma is similar in all three species.

Breakpoint position on 17q identifies the most aggressive neuroblastoma tumors

Gain of chromosome arm 17q is a powerful prognostic factor in neuroblastoma, and the distribution of 17q breakpoints suggests that the dosage of one or more genes in 17q22-23 to 17qter is critical for tumor progression. To identify the smallest region of 17q gain, we used eight probes to map translocation breakpoints in 48 primary neuroblastoma tumors. We identified at least five different breakpoints, all localized within the proximal part of 17q (from D17Z1 to MPO). The shortest region of gain identified by these probes extends from MPO (17q23.1) to 17qter. Surprisingly, we found that breakpoints localized proximal to ERBB2 (17q12) were associated with significantly better patient survival than breakpoints localized distal to ERBB2. Breakpoints localized distal to ERBB2 identified patients with a particularly poor prognosis, higher mitotic karyorrhectic index, and stage 4 disease. This implies that breakpoint position on 17q is a discriminative factor within this prognostically poor group of patients. This result also suggests that the biological effect of 17q gain during neuroblastoma progression has a complex basis. We propose that this involves dosage alterations of genes localized on both sides of the 17q breakpoints, with a gene or genes mapping between 17cen and 17q12 acting to suppress progression, and a gene or genes mapping between 17q23.1 and 17qter acting to promote tumor progression.