In:
Cancer Research, American Association for Cancer Research (AACR), Vol. 71, No. 8_Supplement ( 2011-04-15), p. 4823-4823
Abstract:
Background: Genetic heterogeneity is a hallmark of cancer and significant evolution occurs locally and at metastatic sites with disease progression. This heterogeneity might contribute significantly to therapy resistance. Since systematic in depth analyses are lacking in head and neck squamous cell carcinomas (HNSCC), we established and tested a protocol that enables comprehensive single cell analyses of cancer cells from primary tumors and metastasis. Material and Methods: From matched primary tumors and lymph node metastases of two HNSCC patients, single cell suspensions were generated and sedimented on positively charged glass slides at low density. Epithelial tumor cells were identified with double-immunofluorescence staining for CD44v6 and CK5/14. Twelve to 14 double-positive cells were isolated via micromanipulation from each tumor and an adapter-linker PCR was used for whole genome amplification of single cells. Sequencing of TP53 was performed on genomic DNA from primary tumors as well on single cell amplification products. An allele-drop-out experiment was performed to control for artificial allelic loss. Fluorescence-in-situ-hybridization (FISH) was used to determine the copy number of chromosome 17 and TP53-gene loci, respectively. Results: Two different heterozygous TP53 mutations were detected in both cases. On the single cell level, we observed an unexpected variation of wild-types, heterozygous mutations and homozygous mutations on the investigated mutation sites. This mutational distribution was significantly different from the allele-drop-out experiment (drop-out rate: 8%). In one we found an expansion of mutated clones in metastasis, and in the other patient a transmission of the genetic changes between the primary tumor and the lymph node metastasis. Interestingly, our preliminary data indicate a polyclonal origin of the metastasis. Conclusion: Our protocol is feasible to study comprehensively genetic heterogeneity between primary tumors and metastases on a single-cell level. The single cell amplification products tested for TP53 mutations can be used for several other genetic studies, including genome-wide methods such as CGH. Our initial data revealed an unexpected intratumoral genetic heterogeneity in primaries and metastases of HNSCC. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4823. doi:10.1158/1538-7445.AM2011-4823
Type of Medium:
Online Resource
ISSN:
0008-5472
,
1538-7445
DOI:
10.1158/1538-7445.AM2011-4823
Language:
English
Publisher:
American Association for Cancer Research (AACR)
Publication Date:
2011
detail.hit.zdb_id:
2036785-5
detail.hit.zdb_id:
1432-1
detail.hit.zdb_id:
410466-3
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