Role of exosomal proteins in cancer diagnosis

Abstract

Exosomes are emerging as a new type of cancer biomarkers. Exosome is a bilayered nano-sized vesicle secreted by various living cells in all body fluids. Based on the expanding albeit incomplete knowledge of their biogenesis, secretion by cells and cancer cell-specific molecular and genetic contents, exosomes are viewed as promising, clinically-relevant surrogates of cancer progression and response to therapy. Preliminary proteomic, genetic and functional profiling of cancer cell-derived or cancer plasma-derived exosomes confirms their unique characteristics. Alterations in protein or nucleic acid profiles of exosomes in plasma correlate with pathological processes of many diseases including cancer. However, previous studies on exosome application in cancer diagnosis and treatment mainly focussed on miRNAs. With the development of rapid large-scale production, purification, extraction and screening of exosomal contents, exosomal protein application can be explored for early stage cancer diagnosis, monitoring and prognosis evaluation. Here, we summarized the recent developments in application of exosomal proteins for cancer diagnosis.

Cholangiocyte‐Derived Exosomal Long Noncoding RNA H19 Promotes Hepatic Stellate Cell Activation and Cholestatic Liver Fibrosis

“…Recently, exosomes have drawn significant attention as essential mediators of intercellular communication under both physiological and pathological conditions . Recent studies suggested that serum, saliva, or urine exosomal cargos can be used as potential biomarkers for low‐invasive diagnoses of cancers . Diagnosis of chronic liver disease at an early stage instead of irreversible and life‐threatening advanced stages is challenging because of the lack of noninvasive or low‐invasive approaches and long asymptomatic disease progression.…”

Identification of LEA, a podocalyxin‐like glycoprotein, as a predictor for the progression of colorectal cancer

“…There are increasing evidences that cancer‐derived exosomes may contribute to tumorigenesis and metastasis and served as a potential biomarker . Meanwhile, due to their presence in most body fluids, exosomes might sever as noninvasive clinical biomarkers . Accordingly, we extracted exosomes from CL187 cell supernatant and CRC patient peripheral blood, and demonstrated that LEA/PODXL highly accumulated in the exosomes using ND‐1‐probed western blotting assay.…”

“…58,59 Meanwhile, due to their presence in most body fluids, exosomes might sever as noninvasive clinical biomarkers. 60 Accordingly, we extracted exosomes from CL187 cell supernatant and CRC patient peripheral blood, and demonstrated that LEA/PODXL highly accumulated in the exosomes using ND-1-probed western blotting assay. To our best knowledge, it is the first time to find the LEA/PODXL expression in cancer cell-derived exosomes.…”

Lipid Nanovesicles by Microfluidics: Manipulation, Synthesis, and Drug Delivery

“…One of the most prevalent strategies is to integrate immunoaffinity isolation of exosomes into the microfluidic device. The capture antibodies, such as exosome‐associated tetraspanins (e.g., CD9, CD63, and CD81), or cancer‐associated proteins (e.g., EpCAM and GPC‐1), can be immobilized onto the surfaces of microchannels or microstructures. For example, PDMS micropillar arrays functionalized with multiwall carbon nanotubes (MWCNTs) have been used for rapid exosome isolation with >80% recovery under an optimized sample flow rate of 1 mL h −1 ( Figure a) .…”