Barrett, M.

Bubendorf, L.

Lorber, T.

Perrina, V.

Rau, S.

Ruiz, C.

RERO DOC Digital Library

translational research52P MULTIPARAMETER PLOIDY PROFILING: A POWERFULTOOLTOINVESTIGATE THE GENOMICS OF DIPLOID TUMORPOPULATIONST. Lorber1, S. Rau1, V. Perrina1, M. Barrett2, C. Ruiz1, L. Bubendorf11Molecular Pathology, Institute of Pathology-University Hospital Basel, Basel,Switzerland2Mayo Clinic Cancer Center, Mayo Clinic Cancer Center, Scottsdale, AZ, USAAim: Genomic intratumor heterogeneity is an increasingly recognized phenomenon invarious solid tumors. However, most methods are not designed to resolve the complexityof mixed cell populations. We have therefore developed the method of MultiparameterPloidy Profiling (MPP). By applying this technology on tumor specimens fromnon-small cell lung cancer (NSCLC) we aim to decipher and genomically investigate alltumor populations (sharing same ploidy) present in the tumor specimens.Methods: MPP involves isolation of nuclei from tissues, multiparameter flow-sortingof tumor populations by DNA content and specific tumor markers, and profilinggenomes using high resolution array comparative genomic hybridization (aCGH) andnext generation sequencing (NGS). As some tumors are diploid by flow cytometry, thespecific lineage marker TTF1 (NSCLC: adenocarcinomas) was used to separate thesefrom normal cells. Fluorescence-in-situ hybridization (FISH) andimmunohistochemistry (IHC) were performed on sorted nuclei and on whole tissuesections to validate results.Results: MPP allowed sorting of different tumor populations within a single tumorspecimen, while excluding non-neoplastic contamination in downstream analysis withaCGH and NGS. We separated three different tumor populations from a single primaryNSCLC with a TTF1 multiparameter sort. We detected significant differences in copynumbers, e.g. a CDKN2A homozygous deletion only present in the diploid tumorpopulation. Finally, we used population-specific genomic data to infer the clonalrelationship and to postulate the evolution of these tumor populations within singletumor specimens.Conclusions: Most importantly MPP enables the separation of diploid tumorpopulations from diploid, benign stromal cells that can serve as reference for genomicprofiling studies, where germline DNA is otherwise not available. To our knowledge,we for the first time purifiied diploid tumor populations from normal cells in amultiparameter sort and genomically characterized them. We also demonstrated thatthe analysis of diploid tumor populations within a single biopsy is crucial for theunderstanding of the clonal composition and evolution of a given tumor.Disclosure: All authors have declared no conflicts of interest.© European Society for Medical Oncology 2015. Published by Oxford University Press on behalf of the European Lung Cancer Conference (ELCC) 2015 organisers.All rights reserved. For permissions, please email: journals.permissions@oup.com.abstractsAnnals of Oncology 26 (Supplement 1): i10–i14, 2015doi:10.1093/annonc/mdv045.16

52PMULTIPARAMETER PLOIDY PROFILING: A POWERFUL TOOL TO INVESTIGATE THE GENOMICS OF DIPLOID TUMOR POPULATIONS

http://doc.rero.ch/record/296648/files/mdv045.16.pdf

52PMULTIPARAMETER PLOIDY PROFILING: A POWERFUL TOOL TO INVESTIGATE THE GENOMICS OF DIPLOID TUMOR POPULATIONS

Abstract

Similar works

Full text

Available Versions

RERO DOC Digital Library