Abstract 4918
Background
Oncogenic MET signaling is often deployed by tumors for malignant transformation through genomic events like tyrosine kinase domain mutations, juxtamembrane splicing mutation and amplified copy numbers, which can be inhibited by c-MET small molecule inhibitors. We present biochemical and clinical findings on a polymorphism of MET, which is common in the East Asian population.
Methods
Germline DNA (gDNA) of lung, nasopharyngeal, liver, breast, gastric and colon cancer cohorts among East Asians (n = 1,076) were genotyped for MET (p.N375S) polymorphism using digital droplet PCR (ddPCR). Relapse free survival (RFS) with curative intent was compared using log-rank test. Screening for protein-protein interaction was performed with SILAC. Clinical study is now enrolling MET-N375S+ squamous cell (SCC) head and neck patients to be given 30mg afatinib daily. Treatment outcome was determined with F-FDG PET/CT scan. Baseline (BL) and post-treatment biopsies were analyzed with immunohistochemistry for response biomarkers and in situ hybridization-proximity ligation assay (ISH-PLA) for receptor interaction.
Results
Fraction of the MET-N375S+ cases is comparable across cancer patients and cancer-free controls (9-18%). METN375S was associated with significantly shorter relapse-free survival (RFS) in SCC of the head and neck (HNSCC; P = 0.005) and lung (LUSC; P = 0.029). SILAC revealed interaction of MET-N375S with HER2 (P < 0.05). Two patients with refractory HNSCC who completed 1 cycle of afatinib, a pan-HER inhibitor, showed radiological tumour shrinkage and reduction in metabolic activity, with partial response by RECIST 1.1 measurement observed in one patient. Evaluable BL biopsy showed strong MET-HER2 interaction (ISH-PLA) with strong staining of phosphorylated MET and HER2 (IHC), which were significantly reduced post-treatment, indicative of successive intervention of MET-N375S/HER2 signaling.
Conclusions
We established MET-N375S as a biologically-distinct molecular subset of SCC that drives malignancy through HER2 signaling, and could serve as a predictive biomarker to select refractory patients with dismal prognosis for afatinib treatment.
Clinical trial identification
NCT03938012. Actual study start date: October 3, 2017; Estimated primary completion date: October 2021; Estimated study completion date: October 2022.
Editorial acknowledgement
Legal entity responsible for the study
National University Cancer Institute, Singapore.
Funding
National Medical Research Council, Singapore.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5877 - Efficacy of anti-PD(L)1 treatment in patients with metastatic urothelial cancer based on mRNA- and protein- based PD-L1 determination: Results from the multicentric, retrospective FOsMIC trial
Presenter: Jonas Jarczyk
Session: Poster Display session 3
Resources:
Abstract
5204 - A differential bladder microbiota composition is associated with tumor grade in bladder cancer.
Presenter: Monica Parra-Grande
Session: Poster Display session 3
Resources:
Abstract
4904 - Molecular characterization of metastatic urothelial carcinoma (mUC) in prior or current smokers (PCS) vs non-smokers (NS)
Presenter: Victor Sacristan Santos
Session: Poster Display session 3
Resources:
Abstract
5370 - Evaluation of different diagnostic methods for identification of FGFR alteration in advanced urothelial carcinomas: Proficiency Results based on multiple RNA extraction kits and mutation detection methods
Presenter: Veronika Weyerer
Session: Poster Display session 3
Resources:
Abstract
2579 - Title: Genomic characterization of non-schistosomiasis-related squamous cell carcinoma (NSR-SCC) of the urinary bladder: a retrospective study of potential prognostic and predictive biomarkers
Presenter: Esmail Al-ezzi
Session: Poster Display session 3
Resources:
Abstract
2203 - TiNivo: Tivozanib combined with nivolumab results in prolonged progression free survival in patients with metastatic renal cell carcinoma (mRCC). Final Results.
Presenter: Philippe Barthelemy
Session: Poster Display session 3
Resources:
Abstract
4712 - First-Line Pembrolizumab (pembro) Monotherapy for Advanced Non‒Clear Cell Renal Cell Carcinoma (nccRCC): Updated Follow-Up for KEYNOTE-427 Cohort B
Presenter: Cristina Suárez
Session: Poster Display session 3
Resources:
Abstract
2091 - First-Line Pembrolizumab (pembro) Monotherapy in Advanced Clear Cell Renal Cell Carcinoma (ccRCC): Updated Follow-Up For KEYNOTE-427 Cohort A
Presenter: James Larkin
Session: Poster Display session 3
Resources:
Abstract
2368 - Association Between Depth of Response and Overall Survival: Exploratory Analysis in Patients With Previously Untreated Advanced Renal Cell Carcinoma (aRCC) in CheckMate 214
Presenter: Viktor Grünwald
Session: Poster Display session 3
Resources:
Abstract
6008 - Quality of life in previously untreated patients with advanced renal cell carcinoma (aRCC) in CheckMate 214: updated results
Presenter: David Cella
Session: Poster Display session 3
Resources:
Abstract