A recent study by Nagoya University researchers revealed that microRNAs in
urine could be a promising biomarker to diagnose brain tumors. Their
findings, published in the journal ACS Applied Materials & Interfaces,
have indicated that regular urine tests could help early detection and
treatment of brain tumors, possibly leading to improved patient survival.
Early diagnosis of brain tumors is often difficult, partly because most
people undergo a brain CT or MRI scan only after the onset of neurological
deficits, such as immobility of limbs, and incapability of speech. When
brain tumors are detected by CT or MRI, in many cases, they have already
grown too large to be fully removed, which could lower patients’ survival
rate. From this perspective, accurate, easy, and inexpensive methods of
early brain tumor detection are strongly desired.
As a diagnostic biomarker of cancerous tumors, microRNAs (tiny molecules of
nucleic acid) have recently received considerable attention. MicroRNAs are
secreted from various cells, and exist in a stable and undamaged condition
within extracellular vesicles in biological fluids like blood and urine.
Nagoya University researchers focused on microRNAs in urine as a biomarker
of brain tumors. “Urine can be collected easily without putting a burden on
the human body,” says Nagoya University Associate Professor Atsushi Natsume,
a corresponding author of the study.
“Urine-based liquid biopsy hadn’t been fully investigated for patients with
brain tumors, because none of the conventional methodologies can extract
microRNAs from urine efficiently in terms of varieties and quantities. So,
we decided to develop a device capable of doing it.”
The new device they developed is equipped with 100 million zinc oxide
nanowires, which can be sterilized and mass-produced, and is therefore
suitable for actual medical use. The device can extract a significantly
greater variety and quantity of microRNAs from only a milliliter of urine
compared to conventional methods.
Their analysis of microRNAs collected using the device from the urine of
patients with brain tumors and non-cancer individuals revealed that many
microRNAs derived from brain tumors actually exist in urine in a stable
condition.
Next, the researchers examined whether urinary microRNAs can serve as a
biomarker of brain tumors, using their diagnostic model based on the
expression of microRNAs in urine samples from patients with brain tumors and
non-cancer individuals. The results showed that the model can distinguish
the patients from non-cancer individuals at a sensitivity of 100% and a
specificity of 97%, regardless of the malignancy and size of tumors. The
researchers thus concluded that microRNAs in urine is a promising biomarker
of brain tumors.
The researchers hope that their findings will contribute to early diagnosis
of aggressive types of brain cancer, like glioblastomas, as well as other
types of cancer. Dr. Natsume says, “In the future, by a combination of
artificial intelligence and telemedicine, people will be able to know the
presence of cancer, whereas doctors will be able to know the status of
cancer patients just with a small amount of their daily urine.”
Reference:
Urinary MicroRNA-Based Diagnostic Model for Central Nervous System Tumors
Using Nanowire Scaffolds by Yotaro Kitano, Kosuke Aoki, Fumiharu Ohka,
Shintaro Yamazaki, Kazuya Motomura, Kuniaki Tanahashi, Masaki Hirano,
Tsuyoshi Naganawa, Mikiko Iida, Yukihiro Shiraki, Tomohide Nishikawa,
Hiroyuki Shimizu, Junya Yamaguchi, Sachi Maeda, Hidenori Suzuki, Toshihiko
Wakabayashi, Yoshinobu Baba, Takao Yasui and Atsushi Natsume, 1 April 2021,
Applied Materials & Interfaces.
DOI: 10.1021/acsami.1c01754
Tags:
Medical Science