A circulating tumor cell-based digital assay for the detection of EGFR T790M mutation in advanced non-small cell lung
Jing Wang1, Na Sun2, Yi-Te Lee3
1Department of Pathology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, P. R. China. hongguang_702@163.com and California NanoSystems Institute, Crump Institute for Molecular Imaging, Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA 90095, USA.
Abstract:
Determining the status of epidermal growth factor receptor (EGFR) T790M mutation is crucial for guiding further treatment intervention in advanced non-small cell lung cancer (NSCLC) patients who develop acquired resistance to initial EGFR tyrosine kinase inhibitor (TKI) treatment. Circulating tumor cells (CTCs) which contain plentiful copies of well-preserved RNA offer an ideal source for noninvasive detection of T790M mutation in NSCLC. We developed a CTC-based digital assay which synergistically integrates NanoVelcro Chips for enriching NSCLC CTCs and reverse-transcription droplet digital PCR (RT-ddPCR) for quantifying T790M transcripts in the enriched CTCs. We collected 46 peripheral arterial and venous blood samples from 27 advanced NSCLC patients for testing this CTC-based digital assay. The results showed that the T790M mutational status observed by the CTC-based digital assay matched with those observed by tissue-based diagnostic methods. Furthermore, higher copy numbers of T790M transcripts were observed in peripheral arterial blood than those detected in the matched peripheral venous blood. In short, our results demonstrated the potential of the NanoVelcro CTC-digital assay for noninvasive detection of the T790M mutation in NSCLC, and suggested that peripheral arterial blood sampling may offer a more abundant CTC source than peripheral venous blood in advanced NSCLC patients.
Insights
A new NanoVelcro CTC-digital assay accurately detects the EGFR T790M mutation in non-small cell lung cancer (NSCLC) patients. Peripheral arterial blood may provide a richer source of circulating tumor cells (CTCs) for this noninvasive test.
Area of Science:
- Oncology
- Molecular Diagnostics
- Genetics
Background:
- Acquired resistance to EGFR tyrosine kinase inhibitors (TKIs) in advanced non-small cell lung cancer (NSCLC) necessitates monitoring for the T790M mutation.
- Epidermal growth factor receptor (EGFR) T790M mutation status is critical for guiding subsequent treatment strategies.
- Circulating tumor cells (CTCs) offer a promising noninvasive source for molecular profiling due to abundant, well-preserved RNA.
Purpose of the Study:
- To develop and validate a novel assay for noninvasive detection of the EGFR T790M mutation in NSCLC.
- To evaluate the efficacy of a NanoVelcro Chip-based CTC enrichment combined with reverse-transcription droplet digital PCR (RT-ddPCR).
- To compare T790M detection in peripheral arterial versus venous blood samples.
Main Methods:
- Development of a CTC-based digital assay integrating NanoVelcro Chips for NSCLC CTC enrichment.
- Quantification of T790M transcripts in enriched CTCs using RT-ddPCR.
- Analysis of 46 peripheral arterial and venous blood samples from 27 advanced NSCLC patients.
Main Results:
- The CTC-based digital assay demonstrated concordance with tissue-based diagnostic methods for T790M mutational status.
- Higher copy numbers of T790M transcripts were detected in peripheral arterial blood compared to matched peripheral venous blood.
- The assay showed potential for noninvasive T790M mutation detection in NSCLC.
Conclusions:
- The NanoVelcro CTC-digital assay is a viable tool for noninvasive T790M mutation detection in NSCLC.
- Peripheral arterial blood sampling may yield a more substantial CTC yield than venous sampling in advanced NSCLC.
- This approach facilitates personalized treatment decisions for NSCLC patients with acquired resistance to EGFR TKIs.
