Multiplex Measurement of Tumor Biomarkers Associated with Colorectal Adenocarcinoma Using Novel Sample Types

Discovering and Validating Tumor Biomarkers with Luminex^® Assays

Discovery of new tumor biomarkers and their roles in cancer progression is an intense research area. Testing strategies that utilize a combination of proteins associated with cancers may improve diagnosis and monitoring chemotherapy in patients.

Multiplex Immunoassays for Detection

Multiplex immunoassays are a valuable tool for investigating potential biomarkers in serum associated with cancer. We report here the use of a 28-plex Luminex performance immunoassay to measure tumor biomarkers in serum, plasma, and tissue lysates. Sera from late-stage colorectal cancer (CRC) patients have several potential tumor biomarkers at higher levels than sera from healthy donors.

Tissue Lysate Validation

Tissue lysates prepared from late-stage CRC and healthy adjacent fresh-frozen tissue were used to measure:

• CEA
• CA19-9
• IL-8
• MIF

The levels of MIF and IL-8 in these tissue lysates were validated using the Jess™ capillary-based automated Western blot system.

Stability Testing and Applications

Stability testing of tumor biomarkers in EDTA, heparin, Streck® Cell-Free BCT®, and Streck Protein Plus plasma samples from healthy donors after 0, 3, and 5 days at room temperature revealed:

• Stabilization of most analyte concentrations using Streck tubes
• Exceptions: ENO-2 and CYFRA21-1

Multiplex immunoassays are a valuable tool for the discovery and development of soluble tumor biomarkers associated with cancer.