Article

KIF5B-ALK, a Novel Fusion Oncokinase Identified by an Immunohistochemistry-based Diagnostic System for ALK-positive Lung Cancer

The Cancer Institute, Japanese Foundation for Cancer Research, Japan.
Clinical Cancer Research (Impact Factor: 8.19). 05/2009; 15(9):3143-9. DOI: 10.1158/1078-0432.CCR-08-3248
Source: PubMed

ABSTRACT EML4-ALK is a transforming fusion tyrosine kinase, several isoforms of which have been identified in lung cancer. Immunohistochemical detection of EML4-ALK has proved difficult, however, likely as a result of low transcriptional activity conferred by the promoter-enhancer region of EML4. The sensitivity of EML4-ALK detection by immunohistochemistry should be increased adequately.
We developed an intercalated antibody-enhanced polymer (iAEP) method that incorporates an intercalating antibody between the primary antibody to ALK and the dextran polymer-based detection reagents.
Our iAEP method discriminated between tumors positive or negative for EML4-ALK in a test set of specimens. Four tumors were also found to be positive for ALK in an archive of lung adenocarcinoma (n = 130) and another 4 among fresh cases analyzed in a diagnostic laboratory. These 8 tumors were found to include 1 with EML4-ALK variant 1, 1 with variant 2, 3 with variant 3, and 2 with previously unidentified variants (designated variants 6 and 7). Inverse reverse transcription-PCR analysis revealed that the remaining tumor harbored a novel fusion in which intron 24 of KIF5B was ligated to intron 19 of ALK. Multiplex reverse transcription-PCR analysis of additional archival tumor specimens identified another case of lung adenocarcinoma positive for KIF5B-ALK.
The iAEP method should prove suitable for immunohistochemical screening of tumors positive for ALK or ALK fusion proteins among pathologic archives. Coupling of PCR-based detection to the iAEP method should further facilitate the rapid identification of novel ALK fusion genes such as KIF5B-ALK.

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    • ". The intercalated antibody-enhanced polymer method was used for the sensitive detection of ALK, as described previously (Takeuchi et al., 2009). "
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    ABSTRACT: Fetal lung interstitial tumor (FLIT) is a recently reported type of congenital lung lesion comprising solid and cystic components. The pathological features include unique interstitial mesenchyme-based cell proliferation, and differ from other neoplasms represented by pleuropulmonary blastoma or congenital peribronchial myofibroblastic tumor. FLIT is extremely rare and its gene expression profile has not yet been reported. We provide the first report of a novel chromosomal rearrangement resulting in α-2-macroglobulin (A2M) and anaplastic lymphoma kinase (ALK) gene fusion in a patient with FLIT. The tumor cells contained a t(2;12)(p23;p13) and were mesenchymal in origin (e.g., inflammatory myofibroblastic tumors), suggesting the involvement of ALK in this case of FLIT. Break apart fluorescence in situ hybridization demonstrated chromosomal rearrangement at ALK 2p23. Using 5'-rapid amplification of cDNA ends, we further identified a novel transcript fusing exon 22 of A2M to exon 19 of ALK, which was confirmed by reverse-transcription polymerase chain reaction. The corresponding chimeric gene was subsequently confirmed by sequencing, including the genomic break point between intron 22 and 18 of A2M and ALK, respectively. Discovery of A2M as a novel ALK fusion partner, together with the involvement of ALK, provides new insights into the pathogenesis of FLIT, and suggests the potential for new therapeutic strategies based on ALK inhibitors. © 2014 Wiley Periodicals, Inc.
    Genes Chromosomes and Cancer 10/2014; 53(10). DOI:10.1002/gcc.22199 · 3.84 Impact Factor
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    • "However, direct sequencing of the breakpoint on genomic DNA level requires either multiplex PCRs or enrichment-based library preparation using multiple oligomers covering the whole potential breakpoint region as baits. Both approaches are handicapped by the low amounts and short lengths of DNA fragments isolated from FFPE material compared to DNA from blood, for example, and by the broad variety of breakpoints among the 5`-fusion partner gene reported to date [2] [9] [10] [11] [12] [13] [14] [15] [16] [17]. To avoid these obstacles, we decided against direct confirmation of genomic breakpoints. "
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    Lung cancer (Amsterdam, Netherlands) 06/2014; 84(3). DOI:10.1016/j.lungcan.2014.03.002 · 3.74 Impact Factor
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    • "The fusion is found about 2-7% in lung cancer [5] [6] [7] [8]. Other genes which can fuse with ALK had also been found, including KIF5B and TFG [7] [9] [10]. In NSCLC never/light smokers without EGFR mutation "
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    Translational oncology 06/2014; 7(3):363–367. DOI:10.1016/j.tranon.2014.04.013 · 3.40 Impact Factor
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