Urinary exosomal proteins as (pan‐)cancer biomarkers: insights from the proteome

Abstract

Exosomes are extracellular vesicles (EVs) released from cells under both physiological and pathological conditions, and may, thus, be present in biofluids. Urine is one of the most accessible biofluids implemented in clinical diagnostics. Recent mass spectrometry (MS)‐based proteomic analyses have enabled high‐throughput, deep proteome profiling of urinary EVs for the discovery, quantification and characterization of cancer‐specific exosome biomarkers. The protein cargo of urine exosomes is emerging as an attractive source for biomarkers, not only for urological cancers, such as prostate, bladder and kidney cancer, but potentially also for nonurological cancers, including gastric, lung, oesophageal and colorectal cancer. More recently, exosome proteomics dissected protein cargo in the lumen and at the surface of EVs, and unexpectedly indicated that RNA‐ and DNA‐binding proteins might also be present on vesicular surfaces. Here, we analyse MS‐based proteomic data on urinary exosomes from cancer patients, and discuss the potential of urinary exosome‐derived biomarkers in cancer.

Proteomics of Extracellular Vesicles: Update on Their Composition, Biological Roles and Potential Use as Diagnostic Tools in Atherosclerotic Cardiovascular Diseases

“…Numerous studies have made it possible to strengthen the knowledge of the exosome proteome in cancers and immunological diseases (e.g., [ 145 , 146 , 147 ]), while the characterization of the cardiovascular exosome proteome is still in development. Several methodologies are available to isolate exosome from other factors such as cell fragments, larger vesicles, or soluble molecules, but the choice of analytical method for exosome purification is critical due to the differences in the protein identifications that have been reported in many studies (e.g., [ 89 , 148 ]).…”

Urinary Extracellular Vesicles and Salt-Losing Tubulopathies: A Proteomic Approach

“…This is demonstrated by only partial overlapping of the identified proteins in several studies of the same models and as well as in uEV from healthy subjects, and these differences depend mainly upon the sample preparation and analysis protocols [24,25]. A recent study compared the uEV proteomes published in 4 different papers: each dataset contained between 1000 and 3500 identified proteins, yet only a minority of the proteins (238 proteins) were common to all studies [32].…”

Exosomes in Prostate Cancer Diagnosis, Prognosis and Therapy

“…Furthermore, the serum exosomes of prostate cancer patients undergoing radiotherapy had increased levels of HSP72, which plays a key role in the stimulation of pro-inflammatory immune responses [68]. Additionally, urinary exosomes are a promising non-invasive biomarker, with a potential use in the diagnosis, prognosis and monitoring of prostate cancer [69].…”