Capturing Metastatic Cancer Cells
A novel instrument for detecting cancer cells in the blood could lead to individualized cancer treatments for patients suffering metastasis. Developed by a Massachusetts General Hospital team led by Daniel Haber, M.D., Ph.D., a renowned cancer scientists supported by the National Foundation for Cancer Research since 2003, the business card-sized CTC-iChip captures circulating tumor cells—referenced in the name of the device— “simply” by running blood from a cancer patient across its surface.
Studded with microposts coated, or “functionalized,” with antibodies designed to seize CTCs in mid-flow, the captured cells can not only be confirmed as tumor-related, but also counted and further analyzed in a variety of ways including molecular characterization. From there, clinicians can decide on the proper treatment or develop new ones. Genetic testing on captured CTCs may give doctors a way to more effectively treat tumors or stop them from spreading.
“Tumors evolve in response to treatment,” said Haber. “They often acquire new genetic features that make them resistant to drugs. If we can monitor those changes in real time, we stand a better chance of matching the right treatments with the right patients against those new changes in their tumors.”
Circulating tumor cells are tumor cells that have become detached from the primary tumor and enter blood circulation. While CTCs occur once in a billion cells, and therefore are extremely rare, they nevertheless may hold a key to metastasis—the stage responsible for the vast majority of cancer deaths.
While still in trial stages, the CTC-iChip could prove to be a powerful tool in managing metastatic cancer care on several fronts. Because it is utilized via a simple blood sample, the need for biopsies and their associated pain and healing period is eliminated. Moreover, CTC monitoring on the spot allows the response of any applied treatments to be monitored in real time, as well as any resistance to them. Additionally, the CTC-iChip captures circulating tumor cells when they are still viable—dead cells are not useful for long-term analysis. The device could dramatically improve treatment and diagnosis for many different types of metastatic cancers, including metastatic breast cancer and glioblastoma.
The CTC-iChip is already responsible for some fundamental discoveries in cancer research. Through experimentation in the lab, the researchers have found a unique and dynamic interconversion of HER2 gene expression: ER+/HER2- cells could spontaneously become ER+/HER2+ and convert back to ER+/HER2-. Because the HER2 gene expression oscillates between “on” and “off” spontaneously in these tumors, researchers reason that the two separate signaling pathways may need to be simultaneously turned off to halt either cell group from repopulating one another and beginning new abnormal growth.
While more research is needed, it is an exciting start to CTC-iChip technology. Dr. Haber and his team are now focused on optimizing CTC culture conditions, improving efficiency, bringing down costs and meeting the remaining challenges to bring individualized therapy into the clinic. And NFCR remains committed to lending its support to these exciting and potentially life-saving efforts.