Quality Assessment of Genetic Markers Used for Therapy Stratification

2003 ◽  
Vol 21 (11) ◽  
pp. 2077-2084 ◽  
Author(s):  
I.M. Ambros ◽  
J. Benard ◽  
M. Boavida ◽  
N. Bown ◽  
H. Caron ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Tumor Cell ◽  
Quality Assessment ◽  
Genetic Markers ◽  
Molecular Genetic ◽  
Molecular Techniques ◽  
Cell Content ◽  
Therapeutic Decisions ◽  
Therapy Stratification

Purpose: Therapy stratification based on genetic markers is becoming increasingly important, which makes commitment to the highest possible reliability of the involved markers mandatory. In neuroblastic tumors, amplification of the MYCN gene is an unequivocal marker that indicates aggressive tumor behavior and is consequently used for therapy stratification. To guarantee reliable and standardized quality of genetic features, a quality-assessment study was initiated by the European Neuroblastoma Quality Assessment (ENQUA; connected to International Society of Pediatric Oncology) Group. Materials and Methods: One hundred thirty-seven coded specimens from 17 tumors were analyzed in 11 European national/regional reference laboratories using molecular techniques, in situ hybridization, and flow and image cytometry. Tumor samples with divergent results were re-evaluated. Results: Three hundred fifty-two investigations were performed, which resulted in 23 divergent findings, 17 of which were judged as errors after re-evaluation. MYCN analyses determined by Southern blot and in situ hybridization led to 3.7% and 4% of errors, respectively. Tumor cell content was not indicated in 32% of the samples, and 11% of seemingly correct MYCN results were based on the investigation of normal cells (eg, Schwann cells). Thirty-eight investigations were considered nonassessable. Conclusion: This study demonstrated the importance of revealing the difficulties and limitations for each technique and problems in interpreting results, which are crucial for therapeutic decisions. Moreover, it led to the formulation of guidelines that are applicable to all kinds of tumors and that contain the standardization of techniques, including the exact determination of the tumor cell content. Finally, the group has developed a common terminology for molecular-genetic results.

scholarly journals Human Ring Chromosomes – New Insights for their Clinical Significance

2013 ◽  
Vol 16 (1) ◽  
pp. 13-19 ◽  
Author(s):  
R.S. Guilherme ◽  
E Klein ◽  
A.B. Hamid ◽  
S Bhatt ◽  
M Volleth ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Clinical Signs ◽  
Ring Chromosome ◽  
Signs And Symptoms ◽  
Molecular Techniques ◽  
Ring Chromosomes ◽  
Multicolor Banding ◽  
Clinical Signs And Symptoms ◽  
Clinical Problems

Abstract Twenty-nine as yet unreported ring chromosomes were characterized in detail by cytogenetic and molecular techniques. For FISH (fluorescence in situ hybridization) previously published high resolution approaches such as multicolor banding (MCB), subcentromere-specific multi-color-FISH (cenM-FISH) and two to three-color-FISH applying locus-specific probes were used. Overall, ring chromosome derived from chromosomes 4 (one case), 10 (one case), 13 (five cases), 14, (three cases), 18 (two cases), 21 (eight cases), 22 (three cases), X (five cases) and Y (one case) were studied. Eight cases were detected prenatally, eight due developmental delay and dysmorphic signs, and nine in connection with infertility and/or Turner syndrome. In general, this report together with data from the literature, supports the idea that ring chromosome patients fall into two groups: group one with (severe) clinical signs and symptoms due to the ring chromosome and group two with no obvious clinical problems apart from infertility.

scholarly journals Phylogenetic analysis of multiprobe fluorescence in situ hybridization data from tumor cell populations

2013 ◽  
Vol 29 (13) ◽  
pp. i189-i198 ◽  
Author(s):  
Salim Akhter Chowdhury ◽  
Stanley E. Shackney ◽  
Kerstin Heselmeyer-Haddad ◽  
Thomas Ried ◽  
Alejandro A. Schäffer ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
In Situ Hybridization ◽  
Tumor Cell ◽  
Fluorescence In Situ Hybridization ◽  
Cell Populations ◽  
Hybridization Data

Central neurocytoma: morphological, flow cytometric, polymerase chain reaction, fluorescence in situ hybridization, and karyotypic analyses

1999 ◽  
Vol 90 (2) ◽  
pp. 348-354 ◽  
Author(s):  
Venita Jay ◽  
Vern Edwards ◽  
Eelco Hoving ◽  
James Rutka ◽  
Laurence Becker ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
In Situ Hybridization ◽  
Ganglion Cells ◽  
Molecular Genetic ◽  
Central Neurocytoma ◽  
Molecular Genetic Analysis ◽  
Fish Analysis ◽  
Chain Reaction ◽  
Polymerase Chain

✓ The results of cytogenetic and molecular genetic analysis of a central neurocytoma are presented. Central neurocytomas are intriguing neoplasms that exhibit primarily neuronal, but also glial characteristics, which indicate an origin from a pluripotential neuroglial precursor. The authors describe an intraventricular neurocytoma in an 11-year-old boy that showed anaplastic features with widespread necrosis and mitoses, as well as extensive calcification and foci that exhibited marked neuronal differentiation with clusters of ganglion cells. Immunohistochemical examination showed prominent synaptophysin and neurofilament positivity and focal glial fibrillary acidic protein positivity. Electron microscopy revealed abundant neuritic processes with microtubules and dense core granules as well as mature ganglion cells. Flow cytometry studies revealed increased S (7.8%) and G2M (9.7%) phase components. Molecular and cytogenetic studies were undertaken to assess whether there were similarities to two other tumor types that exhibit neuronal differentiation, the neuroblastoma and medulloblastoma. Polymerase chain reaction and fluorescence in situ hybridization (FISH) analysis revealed no evidence of amplification of the MYCN oncogene or chromosome 1p deletion, which are common in neuroblastomas. Chromosomal analysis by G banding revealed a complex karyotype, with counts in the near-diploidy range (45–48). Two chromosomes 1 appeared normal on G banding and FISH analysis, with p58 signals present on the distal p arm of both chromosomes 1; however, three additional copies of distal 1q were present in rearrangements with 4 and 7. Although the histological findings indicate a kinship to the neuroblastoma and medulloblastoma, the central neurocytoma appears to have a different karyotypic profile, although more cases need to be assessed using molecular genetic analysis.

Combination of Cytology, Fluorescence In Situ Hybridization for Aneuploidy, and Reverse-Transcriptase Polymerase Chain Reaction for Human Mammaglobin/Mammaglobin B Expression Improves Diagnosis of Malignant Effusions

2004 ◽  
Vol 22 (3) ◽  
pp. 474-483 ◽  
Author(s):  
Michael Fiegl ◽  
Margot Haun ◽  
Anita Massoner ◽  
Jens Krugmann ◽  
Elisabeth Müller-Holzner ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
In Situ Hybridization ◽  
Tumor Cell ◽  
Fluorescence In Situ Hybridization ◽  
Cell Detection ◽  
Malignant Cells ◽  
Chain Reaction ◽  
Tumor Cell Detection ◽  
Polymerase Chain

Purpose The identification of malignant cells in effusions by conventional cytology is hampered by its limited sensitivity. The aim of this study was to improve tumor cell detection in effusions by molecular approaches. Materials and Methods A total of 157 effusions from patients with tumors and 72 effusions from patients without a history or evidence of malignancy were included in this study. All effusion specimens were evaluated in parallel by cytology, fluorescence in situ hybridization (FISH) for aneuploidy, and reverse-transcriptase polymerase chain reaction (RT-PCR) for expression of human mammaglobin (hMAM) and mammaglobin B (hMAM-B). Results In effusions from patients with tumors, the sensitivities of tumor cell detection by cytology, FISH, and hMAM and hMAM-B detection were 46.2%, 53.3%, 36.4%, and 57.7%, respectively. The corresponding specificities were 94.4%, 97.0%, 87.1%, and 88.6%. Notably, a high percentage of effusions containing malignant cells were in fact transudates, indicating the necessity for molecular diagnostic work-up of transudates collected from patients with tumors. Dependent on the tumor type, the use of appropriate marker combinations improved tumor cell detection in effusions significantly. By combining all four diagnostic tests, a positive test result indicating the presence of malignancy was achieved in 81.1%, with a fairly good specificity of 70.1%. Conclusion Molecular techniques are definitely useful to detect malignancy in cytologically negative effusions. Tumor cell detection in effusions can be significantly improved by FISH and PCR techniques applying appropriate molecular markers. This finding should help to improve tumor staging, prognostic assessment, and treatment monitoring.

scholarly journals An update on the detection methods of Parachlamydia acanthamoebae, an atypical agent of pneumonia

2019 ◽  
pp. 86-100
Author(s):  
Avinash Rames
Keyword(s):  
Cell Culture ◽  
In Situ Hybridization ◽  
Molecular Techniques ◽  
Detection Methods ◽  
Pathogenic Role ◽  
Chain Reaction ◽  
Isolation And Identification ◽  
Polymerase Chain ◽  
Koch Postulates

Parachlamydia acanthamoebae (P. acanthamoebae) has been recognized as an emerging agent of pneumonia as it has been identified in human samples via culture-based, molecular and serological techniques. Additionally, studies on animal models have shown that it fulfills the third and fourth Koch postulates to be assigned a pathogenic role. Due to the threat posed by it, multiple tools have been employed in the search for P. acanthamoebae. The methods utilized for its detection would be cell culture based approaches which involve both animal and amoebal cell culture and also molecular techniques that encompasses polymerase chain reaction (PCR), fluorescence in situ hybridization (FISH) and in situ hybridization (ISH). Additionally, immunohistochemistry (IHC) and serology based techniques such as direct and indirect immunofluorescence are also employed with the usage of Western blotting or immunoblotting as confirmatory procedures. This review attempts to describe the variety of techniques that are present in literature for the isolation and identification of P. acanthamoebae.

scholarly journals Tumor cell-intrinsic expression of immune checkpoint molecules revealed by RNA in situ hybridization

2017 ◽  
Vol 28 ◽  
pp. vii28
Author(s):  
U. Harms ◽  
N. Li ◽  
M. Rouault ◽  
K. Wilkens ◽  
X-J Ma ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Tumor Cell ◽  
Immune Checkpoint ◽  
Immune Checkpoint Molecules ◽  
Rna In Situ Hybridization
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