In:
Journal of Clinical Oncology, American Society of Clinical Oncology (ASCO), Vol. 31, No. 15_suppl ( 2013-05-20), p. e22192-e22192
Abstract:
e22192 Background: The frequency and poor prognosis of metastasis colorectal cancer (mCRC) emphasizes the need of better markers for both treatment and prognosis. Here we describe an approach of identifying somatic variants in exonic regions of key cancer genes. Methods: Formalin-fixed paraffin embedded (FFPE) tissues biopsied from mCRC patients were collected. DNA was extracted and sequenced on the Ion Torrrent Personal Genome Machine.For targeted amplification, we used the Ion AmpliSeq Cancer Panel which is designed to detect 739 mutations in 604 loci from 46 oncogenes and tumor suppressor genes with as little as 10ng of input DNA.Sequencing results were then analyzed using the Ampliseq Variant Caller plug-in within Ion Torrent Suite Software. Ingenuity Pathway Software was used to do pathway analysis. Cox regression was tested regarding the potential relationship between the alteration numbers and the clinical factors including response rate, disease free survival and overall survival, etc. Results: Among 10 specimens, we identified 66 genetic alterations in 24 genes after excluding the germline mutations according the dbSNP database. 41% of those alterations were also present in the COSMIC database (Catalogue of Somatic Mutations in Cancer). No clinical factor was found to be significantly associated with the alteration numbers by univariate analysis. Notably, there are 11 genes including the expected APC, BRAF, KRAS, PIK3CA and TP53 that were mutated in at least 2 samples. Pathway analysis identified “Colorectal Cancer Metastasis Signaling” as the top mutated canonical pathway. This analysis further revealed mutated genes in the classic signal pathways of Wnt, PI3K/AKT, and TGF-beta/SMAD as significantly present. Interestingly, 90% of specimens harbored at least one “druggable” alteration (range from 1 ~ 6)that has been linked to a target treatment or is currently being investigated in clinical trials. Those pairs of drug and targeted genes are vemurafenib to BRAF; cetuximab to EGFR; palifermin to FGFR2; pazopanib to FGFR3; AEE 788 to KDR and BEZ235 to PIK3CA. Conclusions: DNA deep sequencing of key cancer related genes enables identification of “druggable” mutations for individual colorectal cancer patients.
Type of Medium:
Online Resource
ISSN:
0732-183X
,
1527-7755
DOI:
10.1200/jco.2013.31.15_suppl.e22192
Language:
English
Publisher:
American Society of Clinical Oncology (ASCO)
Publication Date:
2013
detail.hit.zdb_id:
2005181-5