[Early Diagnosis of Cancer Using Nematoda C. elegans]

Cancer is the leading cause of death in Japan, and one in two people experience cancer in their lifetime. Early diagnosis of cancer is the most important for increasing survival rate of cancer, which is also expected to contribute to decrease budget impact of cancer, but participation rate of cancer screening is still low in Japan. Currently, people need to take multiple examinations to detect different types of cancer, which increases the cost, time and pain burdens for the examinees. Therefore, it is desirable to develop cheaper, non-invasive, as well as sensitive cancer screening methods that can detect multiple types of cancer at the same time. Most of the existing cancer screening tests including imaging diagnosis depend on artificial devices, which usually require high cost to achieve high sensitivity. We have developed a new technique, N-NOSE, which takes advantage of the good olfaction of nematode C. elegans to detect cancer smell in urine samples. N-NOSEexhibited 95.8% sensitivity and 95.0% specificity on 242 urine samples of 10 cancers types tested including those of early stages. C. elegans is easy to be maintained in a laboratory with low cost. In addition, as C. elegans is a hermaphroditic organism with homogeneous genetic background, they show stable and reproducible behavioral results. Therefore, N-NOSEis expected to offer a reasonable and non-invasive cancer screening method which is suitable for regular health checkup.