All Cancer Cells Off at Exit 12!

Metastasis is one of the scariest terms one can hear in regards to cancer. It means that the cancer cells have detached from the original tumor and have started to spread through the lymph and/or blood vessels of the body to later reattach in a new location to start a new tumor. Once cancer metastasizes, it become much harder to treat.

Metastasis
Image Credit: National Cancer Institute

A new device from Tony Jun Huang's lab may help us better understand Metastasis and provide a more effective way to study the phenomenon, as well as allow doctors to better screen cancer patients  to see how they are reacting to treatment.

The device is about the size of two pennies, and allows a quicker and more efficient way to sort cancer cells from blood samples. 

The image over is a mock-up of what happens inside the device. From the top, an unsorted sample flows down to the bottom. As it goes, acoustic waves from either side push white blood cells to one side, while pushing the circulating tumor cells to the other side. This method has proven to have a successful separation rate of more than 83%. 

This method has significant improvements over existing cell separation methods. One method employs tumor-specific antibodies that bind with the cancer cells to flag them, but to use this method the right kind of antibodies must be known ahead of time, which significantly limits the effectiveness of the method. A second method is pretty much a centrifuge with can separate the cells based on size, but these devices can cost anywhere from $200,000 to $1,000,000 and reduce cell viability by up to 99%. In a lot of research, the cells need to be alive in order for anything useful to be gathered from them. 

The new device that relies on acoustics has the potential to solve all of these issues. A continuous sample can be flowed through the device, aiding in speed. The device is about the size of two pennies, a far cry smaller than a huge centrifuge type device. The small and simple size of the device also means that it is rather cheap, and could be disposable, a trait that is very important when dealing with medical tests (no one wants their blood getting mixed up with someone else's in a device that might tell them how well their treatment is going). Further, because the acoustic waves are around the same energy level as the waves used in ultrasonic imagery, they do not damage the cells, and can be used in a clinical setting.

The acoustic separation device
Image Credit: Tony Jun Huang, Penn State

"Looking for circulating tumor cells in a blood sample is like looking for a needle in a haystack," said Professor Huang, and this new cell sorter is like getting a giant electromagnet to place over the haystack in that it makes it so much easier and so much faster. The technology is going to help future research into cancer, as well as be there for doctors to use for diagnosis, prognosis, and treatment check-ups. Cancer is becoming ever-more treatable, and this device is one good step towards making it so.

If you'd like to learn more about the use of standing acoustic waves to sort microparticles, you can read this article published in the journal Lab on a Chip.