The HB-Chip also can process larger-volume blood samples, increasing the ability to find rare CTCs. The microchip is mounted on a standard glass slide, which allows the use of standard pathology tests to identify cancer cells; and the device can be easily opened, giving access to CTCs for additional testing and growth in culture. Experiments comparing the HB-Chip to the CTC-chip found the new device captured more than 90 percent of cancer cells introduced into blood samples – a 25 percent improvement over the CTC-chip. Tests of samples from cancer patients found the redesigned device at least as effective as the original.
The HB-Chip also captured clusters of 4 to 12 CTCs from several patient samples but not from samples to which cancer cells had been added. No previous technology for capturing CTCs has ever found such clumps of tumor cells. "These clusters may have broken off from the original tumor, or they might represent proliferation of CTCs within the circulation," says Mehmet Toner, PhD, director of the BioMicroElectroMechanical Systems Resource Center in the MGH Center for Engineering in Medicine, the paper's senior author. "Further study of these clusters could provide valuable insight in the metastatic process."
Daniel Haber MD PhD, director of the MGH Cancer Center and a co-author of the study, says, "This new technology is a powerful platform that will enable increasingly sophisticated analyses of metastasis and support clinical research in targeted cancer therapies."
While the MGH has filed a patent for the HB-Chip, the research team will continue to develop the technology before potential licensing is explored. The study was supported by grants from Stand Up to Cancer, the Prostate Cancer Foundation, the National Institute for Biomedical Imaging and Bioengineering, the National Cancer Institute and the American Cancer Society, along with several additional funders.
Rotating image of circulating tumor cell cluster isolated from the blood of a patient with metastatic prostate cancer using the HB-Chip.
(Photo Credit: Proceedings of the National Academy of Sciences)
The herringbone pattern of interior surfaces in the HB-Chip brings more circulating tumor cells into contact with the antibody-coated capture surfaces. The inset shows the uniform blood flow through the device.
(Photo Credit: Proceedings of the National Academy of Sciences)
Source: Massachusetts General Hospital