The new device uses a small worm to detect lung cancer cells

Dogs can take advantage of their incredible odor sensation to sniff out different forms of cancer in human respiratory, blood, and urine samples.Similarly, in the laboratory, a much simpler organism, the roundworm C. Elegance, Wriggle towards cancer cells by following the traces of odor. Today, scientists are reporting devices that use small worms to detect lung cancer cells. This “worm-on-chip” may one day help doctors diagnose cancer early and non-invasively.

Researchers will present their results today at the American Chemical Society (ACS) Spring Conference. ACS Spring 2022 is a virtual direct hybrid conference from March 20th to 24th with on-demand access from March 21st to April 8th. The conference will feature over 12,000 presentations on a wide range of scientific topics.

Early diagnosis of cancer is important for effective treatment and survival, says graduate student Nari Chan, who is presenting her work at the conference. Therefore, cancer screening methods should be quick, easy, economical and non-invasive. Currently, doctors diagnose lung cancer by imaging and biopsy, but these methods often do not detect tumors in the early stages. Dogs can be trained to sniff out human cancer, but keeping them in the lab is not practical. Therefore, the project’s principal researchers, Jang and Shin Sik Choi, Ph.D., used a small (about 1 mm long), easy-to-grow in the laboratory, and an abnormal sense of smell, called a nematode. I decided to do it. Develop non-invasive cancer diagnostic tests.

“Lung cancer cells produce a different set of odor molecules than normal cells,” says Choi at Meiji University in South Korea. “The nematodes that live in the soil C. EleganceOther researchers placed the nematodes in a Petri dish, added a drop of human urine, and observed that the nematodes preferentially crawl. Urine sample of a cancer patient. Jang and Choi wanted to create an accurate and easy-to-measure format test.

So the team created a chip from a polydimethylsiloxane elastomer with wells connected to the central chamber with channels at both ends. The researchers placed the chips on an agar plate. A drop of medium from lung cancer cells was added to one end of the chip, and medium from normal lung fibroblasts was added to the other end. They placed the worms in the central chamber and after 1 hour observed more worms crawling towards the lung cancer medium than normal medium.In contrast, worms with mutated olfactory receptor genes odr-3 Did not show this preferred behavior.

Based on these tests, researchers estimated that the device was about 70% effective in detecting cancer cells in diluted cell culture medium. They hope to improve both the accuracy and sensitivity of the method by using worms that have a “memory” of cancer-specific odor molecules because they were previously exposed to cancer cell media. .. Once the team has optimized the worm-on-chip to detect cultured lung cancer cells, they plan to move on to testing urine, saliva, and even breath from people.

We work with doctors to find out if our method can be detected Patient’s lung cancer In the early stages”

ShinSik Choi, Ph.D., Principal Investigator of the project

They also plan to test the device with multiple forms of cancer.

In other studies using worm-on-chips, researchers identified specific odor molecules that attracted them. C. Elegance For lung cancer cells containing a volatile organic compound called 2-ethyl-1-hexanol, which has a floral scent. “I do not know why C. Elegance It’s attracted to lung cancer tissue and 2-ethyl-1-hexanol, but I think the smell is similar to the smell of their favorite food, “says Chan.