CD62L Protein As a Potential Biomarker for Bladder Cancer

Wednesday, 4 October 2017: 17:10
Chesapeake L (Gaylord National Resort and Convention Center)
G. S. Phadke, J. E. Satterwhite (University of Connecticut), D. Choudhary, J. A. Taylor III (University of Connecticut Health Center), and J. F. Rusling (National University of Ireland Galway, Ireland)
Early detection of bladder cancer is crucial for improved patient outcomes, as patients see a sharp decline in 5-year survival rate from 80% to < 35%, at early or late stage diagnosis of the disease respectively. Gene expression studies indicated L-selectin (CD62L) as a potential protein biomarker indicative of metastatic bladder cancer. Here, a quantitative bead-based microfluidic immunoarray for CD62L expression in human serum is described. Sandwich immunoassay is established by surface binding of primary antibody on an 8-electrode carbon array and magnetic beads decorated with multiple detection antibodies and horseradish peroxidase enzyme-labels. Electrochemical detection is conducted by injecting a hydroquinone/hydrogen peroxide activator/mediator mixture for amperometric signal detection. Our analysis of 40 patient samples shows an overall increase in CD62L concentration with progression of disease stage. A drop-off in soluble CD62L is seen for late stage, high-grade metastatic tumors. In-depth statistical analysis is conducted to examine the comparative performance of traditional immunoassay and our modified immunoarray for CD62L.