Detection of MET amplification by droplet digital PCR in peripheral blood samples of non-small cell lung cancer
Ying Fan1,2, Rui Sun3,4, Zhizhong Wang3,4
1State Key Laboratory of Genetic Engineering and MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai, 200438, Shanghai, China.
Purpose:
Mesenchymal-epithelial transition (MET) amplification is one of the mechanisms accounting for the resistance of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in lung cancer patients, as well as the poor prognosis. Fluorescence in situ hybridization (FISH) is the most widely used method for MET amplification detection. However, it is inapplicable when tissue samples were unavailable. Herein, we assessed the value of droplet digital PCR (ddPCR) in MET copy number gain (CNG) detection in non-small cell lung cancer (NSCLC) patients treated with EGFR-TKIs.
Materials And Methods:
A total of 103 cancer tissues and the paired peripheral blood samples from NSCLC patients were collected for MET CNG detection using ddPCR. In parallel, MET amplification in tissue samples was verified by FISH. Also, the relationships between MET CNG and EGFR T790M, as well as the EGFR-TKI resistance were also evaluated using Chi-square or Fisher's exact tests.
Result:
The concordance rate of ddPCR and FISH in detecting MET CNG in tissue samples was 100% (102/102), and it was 94.17% (97/103) for ddPCR method in detecting the MET CNG among peripheral blood and tissue samples. No statistical difference was observed between MET amplification and EGFR T790M (p = 0.65), while MET amplification rate was significantly increased in patients with resistance to third generations of EGFR-TKIs as compared with patients with resistance to first/second EGFR-TKIs (p < 0.05).
Conclusions:
ddPCR is an alternative method to detect MET CNG in both tissues and peripheral blood samples, which is of worthy in clinical promotion.
Insights
Droplet digital PCR (ddPCR) accurately detects MET copy number gain in non-small cell lung cancer (NSCLC) patients, offering a valuable alternative to FISH when tissue is unavailable. This method shows promise for clinical application in EGFR-TKI resistance assessment.
Area of Science:
- Oncology
- Molecular Diagnostics
- Genetics
Background:
- Mesenchymal-epithelial transition (MET) amplification is a key mechanism of resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer (NSCLC).
- Fluorescence in situ hybridization (FISH) is the standard for detecting MET amplification but requires tissue samples, limiting its use.
- Assessing MET copy number gain (CNG) is crucial for understanding and overcoming EGFR-TKI resistance.
Purpose of the Study:
- To evaluate the utility of droplet digital PCR (ddPCR) for detecting MET copy number gain (CNG) in NSCLC patients treated with EGFR-TKIs.
- To compare the performance of ddPCR with FISH for MET amplification detection in tissue samples.
- To assess the feasibility of using ddPCR on peripheral blood samples for MET CNG detection.
Main Methods:
- Collected 103 NSCLC tissue and paired peripheral blood samples.
- Performed MET CNG detection using ddPCR on both sample types.
- Validated MET amplification in tissues using FISH and analyzed correlations with EGFR T790M and TKI resistance.
Main Results:
- ddPCR demonstrated 100% concordance with FISH for MET CNG in tissue samples.
- ddPCR achieved a 94.17% concordance rate when analyzing peripheral blood against tissue samples.
- MET amplification was significantly associated with resistance to third-generation EGFR-TKIs compared to first/second-generation TKIs.
Conclusions:
- ddPCR is a reliable and accurate alternative method for detecting MET CNG in both NSCLC tissue and peripheral blood.
- The findings support the clinical utility and promotion of ddPCR for MET CNG assessment in NSCLC patients.
- ddPCR offers a non-invasive approach for monitoring MET alterations and guiding EGFR-TKI treatment strategies.
