Development of a Novel c-MET-Based CTC Detection Platform.

Area of Science:

• Oncology
• Molecular Biology
• Biotechnology

Background:

• MET oncogene amplification correlates with poor prognosis and drug resistance in various cancers.
• Circulating tumor cells (CTCs) are valuable biomarkers for cancer detection and monitoring.
• Targeting c-MET is a potential therapeutic strategy for MET-amplified malignancies.

Purpose of the Study:

• To develop and validate a novel assay for capturing and characterizing c-MET-expressing CTCs.
• To assess the sensitivity and specificity of the assay for detecting MET-amplified and c-MET-overexpressed cells.
• To evaluate the clinical applicability of the c-MET CTC assay in patients with metastatic carcinomas.

Main Methods:

• Development of a ferromagnetic antibody-based method for capturing c-MET+ CTCs.
• Immunofluorescence staining for c-MET, DAPI, and pan-CK, with exclusion of leukocytes (CD45+).
• Validation using cell line controls and analysis of peripheral blood from healthy volunteers and cancer patients; DNA FISH for MET amplification.

Main Results:

• The assay demonstrated high sensitivity (80%) for MET-amplified cells and good sensitivity (40%-80%) for c-MET-overexpressed cells.
• Specificity was 100% for c-MET-negative cells and in healthy volunteers.
• c-MET CTCs were detected in 6% of metastatic cancer patients (gastric, colorectal, RCC), with MET amplification confirmed by FISH.

Conclusions:

• The c-MET CTC assay is a rapid, noninvasive, sensitive, and specific method for detecting MET-amplified tumor cells.
• The assay successfully identified CTCs with MET amplification in patients with gastric, colorectal, and renal cell carcinoma.
• Further investigation is warranted to determine the clinical utility of this novel c-MET CTC assay.