A team of engineers and physicians at the University of Michigan has developed a prototype portable device that can continuously collect live cancer cells directly from a patient's blood. "Wearable", which has already been tested on animal models, could be an alternative to biopsy and help diagnose and treat cancer more effectively.
Tumors can release more than 1,000 cancer cells into the bloodstream in a single minute. Current methods for capturing blood cancer cells are based on patient samples. Some blood samples return without cancer cells, even in patients with advanced cancer, and a typical sample does not contain more than 10 cancer cells.
For a few hours in the hospital, the new device could continually capture cancer cells directly from the vein, examining much larger volumes of a patient's blood. In animal tests, the cell capture chip in the handheld device captured 3.5 times more cancer cells per milliliter of blood than the current samples collected by blood collection.
"It's the difference between having a security camera that takes a snapshot of a port every five minutes or making a video," explains the device's director of development, Dr. Sunitha Nagrath, associate professor of chemical engineering at the University of Michigan. on the relevancy of this & # 39; wearable & # 39;
Research shows that most cancer cells can not survive in the bloodstream, but those that are most likely to start a new tumor. Usually, these are satellite tumors, called metastases, which are deadly instead of the original tumor. This means that the cancer cells captured in the blood could provide better information to plan treatments than those of a conventional biopsy.
"If we could get enough cancer cells from the blood, we could use them to learn about the biology of the tumor and the direct care of the patients," said Daniel F. "This is the thrill of why we are doing this." Hayes, the lead author of the paper, was published in the journal Nature Communications.
The team tested the new device on dogs at the Flint Animal Cancer Center at Colorado State University (United States). They injected human cancer cells into healthy adult animals, which are eliminated by the dog's immune system within a few hours with no lasting effects.
During the first two hours after the injection, the dogs received a sedative and connected to the device, which examined between 1 and 2 percent of the blood. At the same time, blood was collected every 20 minutes, and the cancer cells in those samples were collected using a chip of the same design.
The device "shrinks" a machine that is usually the size of a furnace to something that can be used on the wrist and connected to an arm vein. It has protocols for blending blood with heparin, a coagulation-preventing drug, and sterilization methods that kill bacteria without damaging immune markers or chip antibodies. It also contains some of the smaller medical pumps in a 3D printed case with the electronics and the cancer cell capture chip.
In the next steps of the device, the team hopes to increase the rate of blood processing. Then they will use the system optimized to capture the cancer cells of the pet dogs that arrive at the center as patients. Now they are developing protein-directed chips on the surfaces of canine breast cancer cells.
The researchers estimate that the device could start testing in humans in three to five years. It would be used to help optimize treatments for human cancers by allowing doctors to see if the cancer cells are producing the molecules that serve as targets for many of the newer anticancer drugs.