Professor Sang-Kwon Lee's team (Department of Semiconductor Science and Technology) has developed a 'Circulating Tumor Cell Separation Chip' that can determine early cancer metastasis using only a small amount of blood, attracting attention.

This result is an advancement from last April's development of a 'cell separation chip' that could separate immune cells by dropping a small amount of blood onto a kit. The work was published in the online edition of the world-renowned journal Nano Letters (impact factor 12.186) on May 31.

Last April, the team that published nanoscale research succeeded in extracting immune cells from a mouse spleen and selectively isolating specific CD4 T cells, which are important in disease and immunology.

This result is significant because the team succeeded in isolating tumor cells from the blood of actual cancer patients. The team artificially introduced 5–10 lung cancer cells (Lung cancer cells, A549) into the blood of two cancer patients and two healthy individuals and succeeded in isolating nearly 70% of the tumor cells.

In particular, the study is significant in that it enables a simple diagnosis of metastasis using only a small blood sample in a short time of 40 minutes.

The Circulating Tumor Cells (CTC) used in this study are trace amounts of cancer cells present in the blood of patients with metastatic cancer. These cells travel through the bloodstream to other tissues, where they adhere to new tissues and develop into different tumor types.

These CTCs normally exist at extremely low levels—about 1–100 cells per billion normal cells—making them practically difficult to detect and isolate accurately.

However, through research applying nanostructures to biomedical applications, the team verified that nanostructures can isolate more than 95% of CTCs present at trace levels in blood. Based on this, they succeeded in developing the diagnostic chip.

They also found that this diagnostic chip, based on quartz nanopillars, demonstrated a separation efficiency four times higher than that of conventional glass-based diagnostic chips.

Professor Sang-Kwon Lee said, 'Because nine out of ten cancer patients die from metastasis, if the public, not only hospitals, could easily detect circulating tumor cells at home, mortality could be dramatically reduced. We plan to file a patent for these findings, and based on this we will pursue the development of a multipurpose portable cancer metastasis diagnostic chip capable of diagnosing various metastatic cancers from a small blood sample.'

Meanwhile, the study involved Professor Sang-Kwon Lee; postdoctoral researcher Dr. Gil-Seong Kim; PhD candidates Dong-ju Kim, Jeong-hwan Hyeong, and Jin-kyung Seol; and researchers from the Yale School of Medicine, where Professor Lee is currently on sabbatical. The work was conducted with support from the National Research Foundation of Korea's Support Program for Basic Research Laboratories and Major Research Centers Program.