Novel NanoVelcro Chip Isolates Intact Circulating Tumor Cells for Diagnostic Testing

An international team of bioengineers has developed a novel "nanoVelcro" device that removes circulating tumor cells (CTCs) from the blood without damaging them.

Samples of CTCs are regarded as the “liquid biopsy” of a tumor, providing convenient access to all disease sites, including primary tumor and fatal metastases. A method that preserves the integrity of CTCs allows molecular and functional analyses that can guide proper therapeutic intervention.

Investigators at the University of California, Los Angeles (USA) and colleagues at RIKEN Advanced Science Institute (Japan) recently described a novel "nanoVelcro" chip that selectively removes CTCs from the blood. The NanoVelcro Chip is about the size of a postage stamp and is composed of nanowires coated with antibodies that recognize CTCs. When two milliliters of blood are passed through the chip, the tumor cells adhere to the nanowires like Velcro. Efficiency of CTC binding ranges from 40% to 70%. The cancer cells are retained by tiny temperature-responsive polymer brushes inside the device. At 37 degrees Celsius, these polymer brushes stick to the tumor cells, but when cooled to four degrees Celsius, they release them, allowing analysis of the cells.

The investigators were able to successfully demonstrate culture expansion and mutational analysis of CTCs isolated by this purification system. In addition, they adopted the combined use of the Thermoresponsive NanoVelcro system with downstream mutational analysis to monitor the disease evolution of an index non-small-cell lung cancer (NSCLC) patient, highlighting its translational value in managing NSCLC.

“With our new system, we can control the blood’s temperature—the way coffeehouses would with an espresso machine—to capture and then release the cancer cells in great purity,” said senior author Dr. Hsian-Rong Tseng, professor of molecular and medical pharmacology at the University of California, Los Angeles. “We combined the thermoresponsive system with downstream mutational analysis to successfully monitor the disease evolution of a lung cancer patient. This shows the translational value of our device in managing non-small-cell lung cancer with underlying mutations.”

A detailed description of the NanoVelcro Chip was published in the December 13, 2014, online edition of the journal ACS Nano.

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University of California, Los Angeles
RIKEN Advanced Science Institute