Laser-based single microstructure isolation platform for whole genome sequencing of single circulating tumor cells

Circulating tumor cells (CTCs) are well known for causing metastasis in the cancer patients because the escaped CTCs from the primary tumor site move to the distant organs through the blood vessels. Thus, the genetic information inside the CTCs is exclusively studied to extract out clinical values of them. Because of such values of CTCs, there have been efforts to detect the CTCs from the patient blood. But only few platforms are available to analyze the whole genome of the CTCs with high resolution after the separation of the CTCs. In this study, we applied Laser-induced Isolation of Microstructure On transferrable-chip and sequencing (LIMO-seq) to retrieve the CTCs and sequence the whole genome using next generation sequencing (NGS). With the simple photo-lithography process, we designed the biochip consisting of the separable microstructures and applied LIMO-seq to solve the current limitations of the single CTC genome analysis. Using the chip, we showed that the CTCs captured by the immune-affinity reaction were readily immuno-fluorescently stained and isolated at a single cell level from the chip using LIMO-seq. We analyzed the whole genome sequences of the isolated single cells for the molecular profiling using NGS technology. Furthermore, we isolated molecule-labelled single CTCs from a breast cancer patient's whole blood to demonstrate clinical potential of this platform. The isolation of the captured CTCs with LIMO-seq will enable CTC-based diagnostics for treating and monitoring the cancer patients.