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Rapid and Cost-Efficient Detection of RET Rearrangements in a Large Consecutive Series of Lung Carcinomas

RET-kinase-activating gene rearrangements occur in approximately 1–2% of non-small-cell lung carcinomas (NSCLCs). Their reliable detection requires next-generation sequencing (NGS), while conventional methods, such as immunohistochemistry (IHC), fluorescence in situ hybridization (FISH) or variant-s...

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Detalles Bibliográficos
Autores principales: Tiurin, Vladislav I., Preobrazhenskaya, Elena V., Mitiushkina, Natalia V., Romanko, Aleksandr A., Anuskina, Aleksandra A., Mulkidjan, Rimma S., Saitova, Evgeniya S., Krivosheyeva, Elena A., Kharitonova, Elena D., Shevyakov, Mikhail P., Tryakin, Ilya A., Aleksakhina, Svetlana N., Venina, Aigul R., Sokolova, Tatiana N., Martianov, Aleksandr S., Shestakova, Anna D., Ivantsov, Alexandr O., Iyevleva, Aglaya G., Imyanitov, Evgeny N.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2023
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10342123/
https://www.ncbi.nlm.nih.gov/pubmed/37445709
http://dx.doi.org/10.3390/ijms241310530
Descripción
Sumario:RET-kinase-activating gene rearrangements occur in approximately 1–2% of non-small-cell lung carcinomas (NSCLCs). Their reliable detection requires next-generation sequencing (NGS), while conventional methods, such as immunohistochemistry (IHC), fluorescence in situ hybridization (FISH) or variant-specific PCR, have significant limitations. We developed an assay that compares the level of RNA transcripts corresponding to 5′- and 3′-end portions of the RET gene; this test relies on the fact that RET translocations result in the upregulation of the kinase domain of the gene and, therefore, the 5′/3′-end expression imbalance. The present study included 16,106 consecutive NSCLC patients, 14,449 (89.7%) of whom passed cDNA quality control. The 5′/3′-end unbalanced RET expression was observed in 184 (1.3%) tumors, 169 of which had a sufficient amount of material for the identification of translocation variants. Variant-specific PCR revealed RET rearrangements in 155/169 (91.7%) tumors. RNA quality was sufficient for RNA-based NGS in 10 cases, 8 of which carried exceptionally rare or novel (HOOK1::RET and ZC3H7A::RET) RET translocations. We also applied variant-specific PCR for eight common RET rearrangements in 4680 tumors, which emerged negative upon the 5′/3′-end unbalanced expression test; 33 (0.7%) of these NSCLCs showed RET fusion. While the combination of the analysis of 5′/3′-end RET expression imbalance and variant-specific PCR allowed identification of RET translocations in approximately 2% of consecutive NSCLCs, this estimate approached 120/2361 (5.1%) in EGFR/KRAS/ALK/ROS1/BRAF/MET-negative carcinomas. RET-rearranged tumors obtained from females, but not males, had a decreased level of expression of thymidylate synthase (p < 0.00001), which is a known predictive marker of the efficacy of pemetrexed. The results of our study provide a viable alternative for RET testing in facilities that do not have access to NGS due to cost or technical limitations.