Association of HER2 ECD and t-PSA serum levels for possible breast cancer diagnosis

Because of the high heterogeneity of breast cancer (BC), BC subtype-specific biomarker panel might be useful for diagnostic BC or becomes an adjunct assay to improve the accuracy of current screening methods. In this study, we measured the protein levels of human epidermal receptor-2 extracellular domain (HER2 ECD) and total prostate-specific antigen (t-PSA) in the serum from 14 BC patients and 8 healthy controls by utilizing our previously developed high-throughput metal-enhanced fluorescence biosensor. The experimental results showed that the summation of HER2 ECD and t-PSA serum levels is proposed in this study. We found that AUC >0.9 of better ability to distinguish HER2+ group from HER2- and healthy groups. In the mean time, if taking the ratio of t-PSA and HER2 ECD serum levels, it is very useful able to differentiate HER2- group from HER2+ and healthy groups at value of AUC >0.8. To our best knowledge, this is for the first time to integrate serum levels of HER2 ECD and t-PSA levels potentially suggested in the screening BC patients for further improving the specificity by using our developed high-throughput metal-enhanced fluorescence biosensor.