Method prolongs lifespan of blood samples

The researchers compared CTC analysis in preserved blood samples and paired fresh samples from the same patients.

There was 92% agreement in the detection of 12 cancer-specific gene transcripts between the fresh and preserved blood samples.

In addition, there was 100% agreement in the detection of a transcript called AR-V7. Recently published studies showed that the presence of AR-V7 mRNA in prostate cancer CTCs predicts resistance to androgen receptor inhibitors, indicating that chemotherapy may be a better option for such patients.

“The ability to preserve the blood for several days and still be able to pick up this clinically relevant biomarker is remarkable,” said study author David Miyamoto, MD, PhD, of MGH Cancer Center.

“This is very exciting for clinicians because AR-V7 mRNA can only be detected using CTCs and not with circulating tumor DNA or other cell-free assays.”

The researchers highlighted the universal nature of their blood preservation approach by pointing to its compatibility with the microfluidic CTC-iChip device, which isolates tumor cells by rapid removal of blood cells. The team said this suggests the potential impact of this work extends beyond cancer detection.

“With exciting breakthroughs in immunotherapy, stem cell transplantation, and regenerative medicine—in which peripheral blood is often the source of cells for functional assays or ex vivo expansion—the ability to preserve live cells will greatly ease logistical timelines and reduce the cost of complex cell-based assays,” Dr Wong said.