The authors report a new type of genetic alteration in lung adenocarcinoma. Fusions of KIF5B with RET kinase are found in 1–2% of lung cancer patients, segregate from other known alterations and can potentially be targeted using RET kinase inhibitors. We identified in-frame fusion transcripts of KIF5B (the kinesin family 5B gene) and the RET oncogene, which are present in 1–2% of lung adenocarcinomas (LADCs) from people from Japan and the United States, using whole-transcriptome sequencing. The KIF5B-RET fusion leads to aberrant activation of RET kinase and is considered to be a new driver mutation of LADC because it segregates from mutations or fusions in EGFR, KRAS, HER2 and ALK, and a RET tyrosine kinase inhibitor, vandetanib, suppresses the fusion-induced anchorage-independent growth activity of NIH3T3 cells.

KIF5B-RET fusions in lung adenocarcinoma