Abstract

Detection of Cancer Related Protease Biomarkers from Blood Spot Cards – “Transition to Viable Companion Diagnostics for Cancer”

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

Proteases represent a large class of enzymes that degrade proteins and have been associated with a wide range of diseases, including cardiovascular; coagulation disorders; inflammatory diseases, diabetes, sepsis; infectious diseases and cancer. While proteases have seen some limited use in disease diagnostics, their full potential has not been exploited. At our UCSD lab we have developed rapid sample to answer protease assays based on fluorescent charge-changing peptide substrates. These liquid biopsy assays can be carried our using small volumes (5ul-10ul) of whole blood, plasma or serum. No sample preparation is required, and the fluorescent peptide products can be detected in about 30 minutes using simple mini-gel electrophoretic formats. We now have significant results showing the elevation of specific proteases (trypsin, chymotrypsin, MMPs and Cathepsins) in pancreatic (PDAC) and other cancers. We also have preliminary results showing protease biomarkers can be detected from samples applied to “Blood Spot Cards.” Use of blood spot cards would represent a paradigm change with major advantages including they require only a small blood sample (5-10ul), are cost $$$ effective (compared to a blood draw tube) and would allow time course studies and companion diagnostics to be carried out (hours, days, weeks).