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Start Over Descriptor "17q" Topic fluorescence in situ hybridization
3 results on '"17q"'

1. Assessment of fine needle aspiration cytology samples for molecular genetic analysis in neuroblastoma.

Author

Mandelia, Ankur, Agarwala, Sandeep, Sharma, Arundhati, Iyer, Venkateswaran, and Bhatnagar, Veereshwar

Subjects
*MOLECULAR genetics, *NEEDLE biopsy, *NEUROBLASTOMA, *FLUORESCENCE in situ hybridization, *DNA copy number variations, *FLUORESCENCE microscopy, *CYTOLOGY, *PATIENTS
Abstract

Purpose: To assess the utility of fine needle aspiration cytology (FNAC) samples for molecular genetic analysis of neuroblastoma. Methods: The case files from the pediatric solid tumor clinic were reviewed to identify 20 neuroblastoma patients whose pre-treatment FNAC slides were preserved in the cytology laboratory. The FNAC slides were destained, air dried and hybridisation with fluorescence in situ hybridisation (FISH) probes was performed as per protocol. All slides were screened and analyzed carefully under the fluorescent microscope. Over four-fold increase of the N-myc signal numbers was defined as N-myc amplification. Focal occurrence of cells (at least 50) showing N-myc amplification surrounded by non-amplified tumor cells was defined as focal N-myc amplification. Presence of three or more signals for the long arm of chromosome 17 was defined as 17q gain. Results: FISH analysis gave informative results for all the FNAC smears in our study. FISH analysis of FNAC smears showed N-myc amplification in 5 (25 %) out of 20 patients and 15 (75 %) showed normal N-myc copy number. Three out of these five patients had homogenous amplification and two patients had focal N-myc amplification, indicating tumor heterogeneity. On investigation of chromosome 17q status, 5 (25 %) out of 20 patients demonstrated gain of 17q and 15 (75 %) patients showed normal 17q status. Four out of the five patients with 17q gain also showed N-myc amplification. Conclusions: The current study indicates that FNAC is a rapid and atraumatic diagnostic method for neuroblastoma which provides sufficient material for molecular genetic analyses by means of FISH. [ABSTRACT FROM AUTHOR]

Published
2013
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2. Methods for evaluating HER2 status in breast cancer : comparison of IHC, FISH, and real-time PCR analysis of formalin-fixed paraffin-embedded tissue

Author

Hans Olsson, Cecilia Gunnarsson, Birgitta Holmlund, and Agneta Jansson

Subjects
Oncology, medicine.medical_specialty, Pathology, Medicin och hälsovetenskap, medicine.drug_class, 17q, In situ hybridization, Biology, Monoclonal antibody, Medical and Health Sciences, law.invention, Pathology and Laboratory Medicine International, Breast cancer, breast cancer, law, Trastuzumab, Internal medicine, HER2, medicine, skin and connective tissue diseases, Polymerase chain reaction, medicine.diagnostic_test, medicine.disease, Real-time polymerase chain reaction, Immunohistochemistry, real-time PCR, medicine.drug, Fluorescence in situ hybridization
Abstract

Hans Olsson,1,2 Agneta Jansson,3 Birgitta Holmlund,3 Cecilia Gunnarsson2,4 1Molecular and Immunological Pathology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden; 2Department of Clinical Pathology and Clinical Genetics, Östergötland County Council, Linköping, Sweden; 3Division of Oncology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden; 4Division of Genetics, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden Abstract: The human epidermal growth factor receptor 2 gene (HER2) is amplified in approximately 15%–20% of all breast cancers. This results in overexpression of the HER2 protein, which is associated with worse clinical outcomes in breast cancer patients. Several studies have shown that trastuzumab, a monoclonal antibody that interferes with the HER2/neu receptor, can improve overall survival in patients with HER2-positive breast cancer. Immunohistochemistry (IHC), combined with different methods for in situ hybridization, is currently used for routine assessment of HER2 status. The aim of the present study was to determine whether real-time polymerase chain reaction (PCR) can serve as a supplementary method for evaluation of HER2 status in primary breast cancer. For this purpose, 145 formalin-fixed paraffin-embedded primary breast cancer samples were tested by real-time PCR amplification of HER2, using amyloid precursor protein as a reference. The results were compared with HER2 status determined by fluorescence in situ hybridization (FISH) and IHC. The specificity, sensitivity, and reproducibility of real-time PCR were evaluated, and a comparison of formalin-fixed and fresh-frozen samples was performed. This showed concordance of 93% between real-time PCR and FISH, and 86% between real-time PCR and IHC. Therefore, we suggest that real-time PCR can be a useful supplementary method for assessment of HER2 status. Keywords: 17q, breast cancer, HER2, real-time PCR

Published
2013

3. Gain of chromosome arm 17q is associated with unfavourable prognosis in neuroblastoma, but does not involve mutations in the somatostatin receptor 2 (SSTR2) gene at 17q24

Author

Tommy Martinsson, Katarina Ejeskär, Frida Abel, and Per Kogner

Subjects
Male, Cancer Research, medicine.medical_specialty, 17q, Biology, Polymerase Chain Reaction, SSTR2, neuroblastoma, Neuroblastoma, Chromosome regions, medicine, Humans, Somatostatin receptor 2, Receptors, Somatostatin, In Situ Hybridization, Fluorescence, Polymorphism, Single-Stranded Conformational, Chromosome Aberrations, medicine.diagnostic_test, Point mutation, Cytogenetics, Regular Article, Prognosis, medicine.disease, Molecular biology, Chromosome 17 (human), Oncology, Chromosome Arm, Mutation, Cancer research, Female, Chromosomes, Human, Pair 17, Fluorescence in situ hybridization
Abstract

Deletion of chromosome arm 1p and amplification of the MYCN oncogene are well-recognized genetic alterations in neuroblastoma cells. Recently, another alteration has been reported; gain of the distal part of chromosome arm 17q. In this study 48 neuroblastoma tumours were successfully analysed for 17q status in relation to known genetic alterations. Chromosome 17 status was detected by fluorescence in situ hybridization (FISH). Thirty-one of the 48 neuroblastomas (65%) showed 17q gain, and this was significantly associated with poor prognosis. As previously reported, 17q gain was significantly associated with metastatic stage 4 neuroblastoma and more frequently detected than both deletion of chromosome arm 1p and MYCN amplification in tumours of all stages. 17q gain also showed a strong correlation to survival probability (P = 0.0009). However, the most significant correlation between 17q gain and survival probability was observed in children with low-stage tumours (stage 1, 2, 3 and 4S), with a survival probability of 100% at 5 years from diagnosis for children with tumours showing no 17q gain compared to 52.5% for those showing 17q gain (P = 0.0021). This suggests that 17q gain as a prognostic factor plays a more crucial role in low-stage tumours. Expression of the somatostatin receptor 2 (SSTR2), localized in chromosome region 17q24, has in previous studies been shown to be positively related to survival in neuroblastoma. A point mutation in the SSTR2 gene has earlier been reported in a human small-cell lung cancer. In this study, mutation screening of the SSTR2 gene in 43 neuroblastoma tumours was carried out with polymerase chain reaction-based single-stranded conformation polymorphism/heteroduplex (SSCP/HD) and DNA sequencing, and none of the tumours showed any aberrations in the SSTR2 gene. These data suggest that mutations in the SSTR2 gene are uncommon in neuroblastoma tumours and do not correlate with either the 17q gain often seen or the reason some tumours do not express SSTR2 receptors. Overall, this study indicates that gain of chromosome arm 17q is the most frequently occurring genetic alteration, and that it is associated with established prognostic factors. © 1999 Cancer Research Campaign

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