2018/04/20
Keio University School of Medicine
Japan Agency for Medical Research and Development
Japan Science and Technology Agency
A research group led by Guest Professor Makoto Suematsu of Keio University (also President of the Japan Agency for Medical Research and Development) and Senior Lecturer Takehiro Yamamoto of the university's Department of Biochemistry, School of Medicine, has successfully and automatically visualized the location of cancer in a label-free and stain-free manner. In a joint study with Researcher Mami Shiota and Research Manager Masayuki Naya of the Advanced Core Technology Laboratories, FUJIFILM Corporation, the team used Surface-enhanced Raman Spectroscopy imaging (hereinafter SERS imaging) to conduct metabolic profiling analysis of cancerous and non-cancerous regions in frozen mouse pathological tissue sections and statistically analyzed the differences between them.
SERS imaging is an advanced technology that utilizes near-field light (spots of strongly enhanced electromagnetic fields), generated by irradiating a special substrate randomly coated with gold nanoparticles with a near-infrared laser beam. This process enhances the Raman scattered light, which reflects the interatomic vibrations of various metabolites within a biological sample on the substrate, and detects it as a two-dimensional image of these metabolites.
Cancer cells are rich in functional molecules containing sulfur atoms, which are involved in regulating cell proliferation and cell death. By interacting with gold nanoparticles, these molecules generate Raman scattered light that reflects their unique interatomic vibrations. Imaging this Raman scattered light makes it possible to visualize the two-dimensional location of these functional molecules within a biological sample. Previously, pathological diagnosis was performed through tissue staining that focused on the morphology and nuclear characteristics of cancer cells. However, factors such as oxidation during specimen processing made accurate analysis difficult. By using SERS imaging on cancerous and non-cancerous regions, the research group has enabled the detection of cancerous areas in label-free, unstained frozen tissue.
This analytical technique, which matches the diagnostic findings of pathologists with the profiling findings from Raman scattered light, has paved the way for the realization of automated qualitative pathological diagnosis of cancer.
The results of this research were published in the online edition of the British scientific journal "Nature Communications" on April 19, 2018, at 19:00 JST (12:00 PM BST).
For the full press release, please see below.