Author of

• 18974

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  P3.02 - Biology/Pathology (ID 620)

  • Event: WCLC 2017
  • Type: Poster Session with Presenters Present
  • Track: Biology/Pathology
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/18/2017, 09:30 - 16:00, Exhibit Hall (Hall B + C)

  • 24001

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    P3.02-053 - Optimization and Characterization of Assays to Identify Met Exon 14 Skipping in FFPE Embedded NSCLC Samples (ID 9881)

    09:30 - 09:30  |  Author(s): O. Geoghegan
    • Abstract

    Background:
    The hepatocyte growth factor (HGF)receptor (MET), is frequently altered in NSCLC. Despite having a significant number of diverse mutations/alterations, randomized trials with MET inhibitors have proved disappointing, with no clinical benefit (1). More recently MET exon 14 skipping alterations have emerged as potential therapeutic targets as MET exon as they inhibit the degradation of Met, prolonging its oncogenic activity (2). Patients with Met exon 14 skipping have been found to sensitive to MET inhibitors such as crizotinib, and clinical trials of MET TKIs in METex14 mutated NSCLC are ongoing (1).
    
    Method:
    A one-step RT-PCR end-point PCR assay to examine for the detection of Met exon14 skipped mRNAs in FFPE was designed, optimized and tested on a cohort of NSCLC patients. Positive samples were confirmed by targeted next-generation sequencing of these samples. Finally RNA in situ hybridization (RISH) was optimised on a cMET exon 14 skipped cell line (NCI-H596) and subsequently performed on full-face sections using a specific BaseScope™ Assay (Techne).
    
    Result:
    Initial studies found that standard end-point PCR resulted in significant false-positives. However, a one-step RT-PCR methodology resolved this issue. Met exon 14 skipped samples were then examined in a cohort of pulmonary sarcomatoid carcinomas (PSCs). In agreement with another study of Caucasian patients (3), we identified Met Exon 14 skipped mutations in 2/20 (10%) of patients. Expression of Met exon 14 skipped was confirmed using targeted resequencing by NGS. RISH was also examined in the same samples.
    
    Conclusion:
    These results demonstrate the optimization of a methodology to robustly detect Met exon 14 mutated patients in FFPE material by a PCR based assay, with results comparable to those obtained in similar studies. This methodology can be utilised by any standard hospital diagnostic laboratory without the need for any specialized technology such NGS, RISH or FISH. A qPCR based version of this assay is currently being optimized and the results will be presented at the meeting. References Reungwetwattana, T. et al., (2017). Lung Cancer 103: 27–37 Pilotto, S. et al. (2017). Ann Transl Med 5(1):2 Saffroy, R. et al (2017). Oncotarget. 2017 Mar 21. doi: 10.18632/oncotarget.16403. [Epub ahead of print]