Integrative analysis of oncogenic fusion genes and their functional impact in colorectal cancer.
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ABSTRACT: Background
Fusion genes are good candidates of molecular targets for cancer therapy. However, there is insufficient research on the clinical implications and functional characteristics of fusion genes in colorectal cancer (CRC).Methods
In this study, we analysed RNA sequencing data of CRC patients (147 tumour and 47 matched normal tissues) to identify oncogenic fusion genes and evaluated their role in CRC.Results
We validated 24 fusion genes, including novel fusions, by three algorithms and Sanger sequencing. Fusions from most patients were mutually exclusive CRC oncogenes and included tumour suppressor gene mutations. Eleven fusion genes from 13 patients (8.8%) were determined as oncogenic fusion genes by analysing their gene expression and function. To investigate their oncogenic impact, we performed proliferation and migration assays of CRC cell lines expressing fusion genes of GTF3A-CDK8, NAGLU- IKZF3, RNF121- FOLR2, and STRN-ALK. Overexpression of these fusion genes increased cell proliferation except GTF3A-CDK8. In addition, overexpression of NAGLU-IKZF3 enhanced migration of CRC cells. We demonstrated that NAGLU-IKZF3, RNF121-FOLR2, and STRN-ALK had tumourigenic effects in CRC.Conclusion
In summary, we identified and characterised oncogenic fusion genes and their function in CRC, and implicated NAGLU-IKZF3 and RNF121-FOLR2 as novel molecular targets for personalised medicine development.
SUBMITTER: Choi Y
PROVIDER: S-EPMC6048111 | biostudies-literature |
REPOSITORIES: biostudies-literature
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