Druggable oncogene fusions in invasive mucinous lung adenocarcinoma
Takashi Nakaoku, Koji Tsuta, Hitoshi Ichikawa, Kouya Shiraishi, Hiromi Sakamoto, Masato Enari, Koh Furuta, Yoko Shimada, Hideaki Ogiwara, Shun-ichi Watanabe, Hiroshi Nokihara, Kazuki Yasuda, Masaki Hiramoto, Takao Nammo, Teruhide Ishigame, Aaron J Schetter, Hirokazu Okayama, Curtis C Harris, Young Hak Kim, Michiaki Mishima, Jun Yokota, Teruhiko Yoshida, Takashi Kohno, Takashi Nakaoku, Koji Tsuta, Hitoshi Ichikawa, Kouya Shiraishi, Hiromi Sakamoto, Masato Enari, Koh Furuta, Yoko Shimada, Hideaki Ogiwara, Shun-ichi Watanabe, Hiroshi Nokihara, Kazuki Yasuda, Masaki Hiramoto, Takao Nammo, Teruhide Ishigame, Aaron J Schetter, Hirokazu Okayama, Curtis C Harris, Young Hak Kim, Michiaki Mishima, Jun Yokota, Teruhiko Yoshida, Takashi Kohno
Abstract
Purpose: To identify druggable oncogenic fusions in invasive mucinous adenocarcinoma (IMA) of the lung, a malignant type of lung adenocarcinoma in which KRAS mutations frequently occur.
Experimental design: From an IMA cohort of 90 cases, consisting of 56 cases (62%) with KRAS mutations and 34 cases without (38%), we conducted whole-transcriptome sequencing of 32 IMAs, including 27 cases without KRAS mutations. We used the sequencing data to identify gene fusions, and then performed functional analyses of the fusion gene products.
Results: We identified oncogenic fusions that occurred mutually exclusively with KRAS mutations: CD74-NRG1, SLC3A2-NRG1, EZR-ERBB4, TRIM24-BRAF, and KIAA1468-RET. NRG1 fusions were present in 17.6% (6/34) of KRAS-negative IMAs. The CD74-NRG1 fusion activated HER2:HER3 signaling, whereas the EZR-ERBB4 and TRIM24-BRAF fusions constitutively activated the ERBB4 and BRAF kinases, respectively. Signaling pathway activation and fusion-induced anchorage-independent growth/tumorigenicity of NIH3T3 cells expressing these fusions were suppressed by tyrosine kinase inhibitors approved for clinical use.
Conclusions: Oncogenic fusions act as driver mutations in IMAs without KRAS mutations, and thus represent promising therapeutic targets for the treatment of such IMAs.
Conflict of interest statement
Disclosure of Potential Conflicts of Interest
No potential conflicts of interest were disclosed.
©2014 American Association for Cancer Research.
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Source: PubMed