Nanowire Assay System Identifies Brain Tumors from Urine

February 23, 2023 | Histopathology

Techniques to isolate and examine very small quantities of extracellular vesicles (EV) as they are naturally excreted in the urine proved to be complex as it required different types of equipment.

At Nagoya University in Japan, scientists attempted to solve this problem and devised a nanowire assay that could capture and detect extracellular vesicles in a urine sample which can be indicative of brain tumor. This mechanism is based on the concept of extracellular vesicles being shed off by brain tumors towards the bloodstream and ultimately ends up in the urine.

Since extracellular vesicles’ surfaces have an electrical charge, this all-in-one assay’s simple well plate is coated with zinc oxide nanowires that attract these vesicles. In each well, the team can then flag and label tumor-specific extracellular vesicles via fluorescently-labeled antibodies. These vesicles are talebearers of tumor hallmarks, ranging from RNA, DNA, to protein markers.

Brain tumors are usually diagnosed when neurological symptoms have already begun or are at an advanced stage, thereby complicating the treatment and a low survival rate. This non-invasive procedure and early detection of brain tumors could improve health and treatment outcomes.

Takap Yasui, one of the proponents of the study, said that liquid biopsy in terms of urine tests is an effective, simple, and non-invasive method as it contains numerous informative molecules which serve as trackers in the identification of disease.

Moreover, Yasui could see how users in the future can run samples through their assay and how they can modify it to specifically detect membrane proteins to identify other types of cancer. This advance in analysis in terms of the expression levels of membrane proteins in the urine is truly a beneficial platform for oncology.