Prostate Cancer Diagnosis in the Clinic Using an 8-Protein Biomarker Panel

Abstract

The inability to distinguish aggressive from indolent prostate cancer is a longstanding clinical problem. Prostate specific antigen (PSA) tests and digital rectal exams cannot differentiate these forms. Because only ∼10% of diagnosed prostate cancer cases are aggressive, existing practice often results in overtreatment including unnecessary surgeries that degrade patients' quality of life. Here, we describe a fast microfluidic immunoarray optimized to determine 8-proteins simultaneously in 5 μL of blood serum for prostate cancer diagnostics. Using polymeric horseradish peroxidase (poly-HRP, 400 HRPs) labels to provide large signal amplification and limits of detection in the sub-fg mL −1 range, a protocol was devised for the optimization of the fast, accurate assays of 100-fold diluted serum samples. Analysis of 130 prostate cancer patient serum samples revealed that some members of the protein panel can distinguish aggressive from indolent cancers. Logistic regression was used to identify a subset of the panel, combining biomarker proteins ETS-related gene protein (ERG), insulin-like growth factor-1 (IGF-1), pigment epithelial-derived factor (PEDF), and serum monocyte differentiation antigen (CD-14) to predict whether a given patient should be referred for biopsy, which gave a much better predictive accuracy than PSA alone. This represents the first prostate cancer blood test that can predict which patients will have a high biopsy Gleason score, a standard pathology score used to grade tumors.

Microfluidics for Peptidomics, Proteomics, and Cell Analysis

“…In addition, the unobstructed capture chamber enables continuous maintenance of flow rates during the label-free assay process, which is in stark contrast to the frequent flow blockages in the highly congested debris field of the membrane system. Jones et al [ 172 ] developed a microfluidic immunoarray to measure an 8-protein panel in serum that can identify patients with prostate cancer and inform the need for biopsy. This 8-biomarker panel contains both common prostate cancer biomarkers and proteins specific to aggressive and metastatic forms ( Figure 5 ).…”

“…Although the MF–MS combination offers a novel alternative to traditional peptidomics and proteomics analyses, its clinical application is still limited. This is because MF devices still need complex manufacturing processes, require considerable resources and equipment, and are complicated in operation [ 172 , 173 ]. It also requires extensive statistical analysis and cost, making it difficult to integrate seamlessly into clinical practice [ 131 ].…”

Biosensors Designed for Clinical Applications

“…We evaluated an 8-biomarker panel of prostate cancer biomarker proteins including some specific for aggressive cancers [34]. These are PSA, vascular endothelial growth factor-D (VEGF-D) [35], gene fusion proteins ETS related gene (ERG) [36], Golgi membrane protein 1 (GOLM-1) [37], pigment epithelial derived factor (PEDF) [33], insulin-like growth factor-1 (IGF-1) [38], insulin-like growth factor binding protein 3 (IGFPB-3) [35,39], and serum monocyte differentiation antigen CD-14 (CD-14) [40].…”

“…Proteins were grouped into models using stepwise selection, and individuals with low significance were removed [41]. Models were PSA alone (model 1), PSA + log(VEGFD) + log(ERG) + log(IGF1) + PEDF +log(CD14) (model 2), and log(VEGFD) + log(IGF1) + PEDF + log(CD14) (model 3) [34].…”

Fascin-1 and Its Role As a Serological Marker in Prostate Cancer: a Prospective case–control Study

“…serum-based biomarkers used for diagnosis of PCa, such as the US FDA approved tests (PSA, fPSA, Prostate Health Index) [7][8][9][10], or clinical laboratory improvement amendments (CLIA)-approved biomarkers (4Kscore) [11][12][13][14], and also test pending approval, such as STHLM3 and STHLM3MRI [15][16][17][18][19] have been developed in recent years. These panels could provide an early detection of PCa, leading to better oncological outcomes and decreasing PCa mortality [20]. However, to date, no blood biomarkers have been able to establish a diagnosis of PCa.…”