Minoru Sakairi and Gerald L. Epstein, discussing measurement technology during the 2015 AAAS-Hitachi Lecture on Science and Society on 9 December, 2015. | AAAS/Stephen Waldron
The nose of nematodes holds promise for a simple, urine-based cancer-screening test. With over 1,000 olfactory receptors, nematodes — also known as roundworms — can acutely detect chemical substances like those associated with colorectal and breast cancers.
“We’re seeing great potential in applying nematodes to cancer testing,” said Minoru Sakairi, chief scientist at the Hitachi Center for Exploratory Research at the 9 December AAAS-Hitachi Lecture, held at AAAS headquarters in Washington, D.C. The event also featured Gerald L. Epstein, former director of the AAAS Center for Science, Technology, and Security Policy.
Sakairi has specialized in ultra-sensitive measurement technology development for three decades. His long-term goal for Hitachi’s nematode project is to develop a convenient and inexpensive cancer test. Patients would buy an over-the-counter kit, providing a urine sample at home that they would then send to a laboratory for testing. Using this method, Sakairi believes, patients can avoid hospital procedures such X-rays and endoscopies.
In Sakairi’s research, nematodes (Caenorhabditis elegans) used their sophisticated olfactory system to sniff out substances associated with colorectal and breast cancer in patients. | Hitachi, Ltd.
To test the concept, Sakairi’s team exposed nematodes to urine samples from healthy participants, as well as participants with cancer. Researchers built a device that used image analysis to detect nematode behavior. When the nematode detects a chemical substance, certain olfactory nerves are stimulated, causing the nematode to be either repelled by or attracted to a substance.
When added to a dish containing a urine sample of a healthy person, Sakairi’s team found that nematodes were repelled and avoided the sample. When exposed to a urine sample of a patient with breast cancer, the nematodes were attracted to the sample. The same held true when nematodes were exposed to urine samples from patients with colorectal cancer.
Going forward, Epstein said researchers should focus on the specific interactions taking place between the organism and the urine sample.
“It’s very important to understand the mechanism of what the nematode is actually doing,” he said.
While an at-home cancer test empowers individuals to be more involved in their treatment, Epstein emphasized that researchers will need to understand the product’s margins of error before it can be approved by the U.S. Food and Drug Administration.
“What is the risk if the device says you’re healthy, but you really have cancer?” Epstein asked.
In addition to his cancer detection research, Sakairi highlighted Hitachi’s work in developing a product that detects explosive materials and other substances, including ammonium nitrate and gunpowder.
The group is developing a new form of Explosive Trace Detection , which identifies trace amounts of explosive materials on the hands of people passing through a security gate.
Epstein, who currently works with the U.S. Department of Homeland Security, said that these systems outlined by Sakairi “are not for detecting the bomb, they’re for detecting the bomber.”
Conventional methods involve using a subject’s hands for swab-sampling and can take up to 20 seconds, Sakairi said. The goal of the team’s new auto-sampling method is to shorten that process to under five seconds.
Using this method, each passenger has a card that they touch to a reader on the boarding gate. The card serves the dual purpose of identifying the passenger and allowing the sampler port to remove substances adhering to the card. An air jet attached to the port removes the material and sends it to a mass spectrometer for identification.
The AAAS-Hitachi lecture series began in 2009, and has featured guests such as then-U.S. Senator John Kerry and faculty members from institutions like Stanford University and Massachusetts Institute of Technology.