'Druggable' alterations detected by Ion Torrent in metastatic colorectal cancer patients

Date
2014
Language
American English
Embargo Lift Date
Committee Members
Degree
Degree Year
Department
Grantor
Journal Title
Journal ISSN
Volume Title
Found At
Spandidos
Can't use the file because of accessibility barriers? Contact us with the title of the item, permanent link, and specifics of your accommodation need.
Abstract

The frequency and poor prognosis of patients with metastatic colorectal cancer (mCRC) emphasizes the requirement for improved biomarkers for use in the treatment and prognosis of mCRC. In the present study, somatic variants in exonic regions of key cancer genes were identified in mCRC patients. Formalin-fixed, paraffin-embedded tissues obtained by biopsy of the metastases of mCRC patients were collected, and the DNA was extracted and sequenced using the Ion Torrent Personal Genome Machine. For the targeted amplification of known cancer genes, the Ion AmpliSeq™ Cancer Panel, which is designed to detect 739 Catalogue of Somatic Mutations in Cancer (COSMIC) mutations in 604 loci from 46 oncogenes and tumor suppressor genes using as little as 10 ng of input DNA, was used. The sequencing results were then analyzed using the Ampliseq™ Variant Caller plug-in within the Ion Torrent Suite software. In addition, Ingenuity Pathway software was used to perform a pathway analysis. The Cox regression analysis was also conducted to investigate the potential correlation between alteration numbers and clinical factors, including response rate, disease-free survival and overall survival. Among 10 specimens, 65 genetic alterations were identified in 24 genes following the exclusion of germline mutations using the SNP database, whereby 41% of the alterations were also present in the COSMIC database. No clinical factors were found to significantly correlate with the alteration numbers in the patients by statistical analysis. However, pathway analysis identified 'colorectal cancer metastasis signaling' as the most commonly mutated canonical pathway. This analysis further revealed mutated genes in the Wnt, phosphoinositide 3-kinase (PI3K)/AKT and transforming growth factor (TGF)-β/SMAD signaling pathways. Notably, 11 genes, including the expected APC, BRAF, KRAS, PIK3CA and TP53 genes, were mutated in at least two samples. Notably, 90% (9/10) of mCRC patients harbored at least one 'druggable' alteration (range, 1-6 alterations) that has been linked to a clinical treatment option or is currently being investigated in clinical trials of novel targeted therapies. These results indicated that DNA sequencing of key oncogenes and tumor suppressors enables the identification of 'druggable' alterations for individual colorectal cancer patients.

Description
item.page.description.tableofcontents
item.page.relation.haspart
Cite As
Fang W, Radovich M, Zheng Y, et al. 'Druggable' alterations detected by Ion Torrent in metastatic colorectal cancer patients. Oncol Lett. 2014;7(6):1761-1766. doi:10.3892/ol.2014.2047
ISSN
Publisher
Series/Report
Sponsorship
Major
Extent
Identifier
Relation
Journal
Oncology Letters
Source
PMC
Alternative Title
Type
Article
Number
Volume
Conference Dates
Conference Host
Conference Location
Conference Name
Conference Panel
Conference Secretariat Location
Version
Final published version
Full Text Available at
This item is under embargo {{howLong}}