Abstract

Rapid Simultaneous Isolation and Detection of Exosome/EV and cfDNA Biomarkers from Cancer Patient Blood Samples

Michael Heller, Distinguished Scientist - Knight Cancer Institute, Center for Cancer Early Detection and Research (CEDAR), Oregon Health & Science University (OHSU)

Multi-omic approaches using different types of biomarkers will be a viable strategy for liquid biopsy diagnostics and early cancer detection. A novel electrokinetic sample to answer device (ACE chip, Biological Dynamics, San Diego, CA) was used to isolate exosomes, extracellular vesicles (EVs) and cell free (cf) DNA from 20-50 µL of cancer patient plasma samples. Fluorescent detection of the cf-DNA and immunostaining for exosome/EV protein biomarkers could then be rapidly carried out directly on-chip. Subsequently, cf-DNA and exosome/EV entrapped RNA could be eluted from the ACE chip, whereupon PCR and sequencing analysis is conducted to identify cancer-related point mutations. Our results show correlation of immunofluorescent detection of exosome/EV glypican-1 and cf-DNA KRAS mutations (G12V, G12D) determined by digital PCR for a number of patient samples from pancreatic and colorectal cancers, where lung cancer patient samples were used as a negative control. This provides further advancement towards integrating multi-omics analysis as a single, on-chip platform, with an ultimate goal of providing seamless sample-to-answer point-of-care liquid biopsy diagnostics.