Commercialized biomarkers: new horizons in prostate cancer diagnostics

Abstract

Limitations with current clinical tools available for diagnosis and prognosis of prostate cancer have resulted in over-diagnosis and costly overtreatment which is impacting on the outcomes and quality of life of men. The biotech industry is investing significant resources into developing more specific biomarkers for prostate cancer detection and patient stratification which would greatly advance the decision-making processes behind prostate cancer management and treatment. In this review we focus on those biomarkers which have been translated into commercial tests available to clinicians. Since these tests aim to fill specific gaps during the decision-making process of prostate cancer management, we have grouped them based on the clinical question they claim to address i.e. improved prostate cancer screening, false negative biopsy dilemma, prognostic tests following a positive biopsy and tests predicting relapse/metastases after surgery. We evaluate each test with respect to its development, platform, clinical validation, biomatrix, regulatory approval status and cost.

Endosomal gene expression: a new indicator for prostate cancer patient prognosis?

“…Our recent discovery of altered endosome biogenesis in prostate cancer [ 14 ] suggests that the biologically relevant changes associated with these endosomal genes have the potential to improve the clinical decision-making process. There are an increasing number of commercial tests for biomarkers that complement the use of PSA (reviewed by Sartori & Chan 2014 [ 9 , 24 ]), but these tests still do not adequately provide an early accurate prognosis for prostate cancer; and coincidentally, have been discovered anecdotally or through biomarker screening rather than by association with a cell biological process. Gene expression may also be altered throughout the course of the cancer growth and differentiation; for example, α methylacyl CoA racemase is an androgen-regulated gene and exhibits variable expression upon androgen-deprivation therapies or androgen-independent disease progression [ 8 ], requiring continued monitoring of these changes.…”

Advances and Perspectives in Prostate Cancer Biomarker Discovery in the Last 5 Years through Tissue and Urine Metabolomics

“…Despite the controversy around the ideal cut-off for the levels of this biomarker, this test obtained FDA approval for men with high PSA levels and/or positive DRE and/or previous negative PB [15,16]. Prostarix test, which is also performed in urine after DRE, was developed using metabolomic approaches and detects four amino acids [17], namely sarcosine, glycine, alanine, and glutamate [13,16]. This test has not yet obtained FDA approval [13], but it is commercially available and is recommended for men with persistent PSA increase and previously negative PB [13,17].…”

Identification and Validation of Leucine-rich α-2-glycoprotein 1 as a Noninvasive Biomarker for Improved Precision in Prostate Cancer Risk Stratification

“…Biological fluids, on the contrary, are easily collected, allow for repeated sampling, and can function as an unbiased source of biomarkers to mirror the complexity of PCa. Unfortunately, the collection of biological samples has been an underfunded effort in many institutional environments; thus, paraffin-embedded prostate specimens have been the primary source of cancer biomarker research so far, which is also reflected in the types of tests approved [8] . Although valuable information can be conveyed from tissue-based tests, these are vulnerable for sampling biases, and consequently utility has been most promising in a postprostatectomy setting [4] .…”