Susanna Fletcher Greer, Chief Scientific Officer at the V Foundation, shared a post on LinkedIn about a paper by Sara Cavallaro et al. published in the Journal of Extracellular Vesicles:
“Liquid biopsies promise a simple way to track cancer through a blood sample, but the signals we need to read are often faint. A team from Harvard Medical School has developed a practical way to make those signals brighter and more stable, both on single circulating tumor cells and on single extracellular vesicles from patient blood. The team is led by Shannon Stott of Mass General, a V Foundation grantee, and I am proud to see the V Foundation support helping move this work forward.
When a tumor grows, cancer cells and nanosized ‘packages’ they release, called extracellular vesicles, circulate through the bloodstream. Those vesicles carry bits of genetic material and proteins that can reveal what’s happening inside a tumor at that very moment, almost like live text messages from the cancer itself. But these signals are usually dim and rare, making them easy to miss.
By developing a method that makes those markers shine brighter and stay visible longer, Shannon Stott’s team has made it possible to more confidently identify which cells and vesicles truly come from the tumor, track changes over time, and compare results between patients.
Shannon Stott team refined a staining method that works a bit like turning up the brightness on a flashlight. Antibodies find the tumor protein, then an attached enzyme deposits many fluorescent ‘tags’ nearby, creating a stronger light signal without requiring special instruments or complex chemistry.
The new approach produced signals more than six times stronger and far more stable than conventional methods. In a pilot study with patients who had glioblastoma, the team detected circulating tumor cells in nearly 60 percent of patients before surgery, and in none of the healthy controls. On average, there were about six tumor cells per milliliter of blood. That may not sound like much, but for a disease as difficult to monitor as glioblastoma, those few cells could provide a window into tumor activity without needing invasive procedures.
The method also worked on extracellular vesicles, the microscopic messengers tumors send into circulation. Shannon Stott showed it’s possible to see multiple tumor markers on a single vesicle, opening the door to tracking how cancers evolve or respond to therapy with just a blood draw.
This is an early but important step toward more precise, patient-friendly cancer monitoring. Next, Shannon Stott plans to expand to more tumor markers and cancer types, test larger patient groups, and adapt the approach for faster, automated systems used in clinical labs.
If successful, this technology could help doctors track treatment response, catch recurrence sooner, and guide more personalized care, simply by reading the blood.
Read this incredible research at ‘Signal Amplification for Fluorescent Staining of Single Particles in Liquid Biopsies: Circulating Tumour Cells and Extracellular Vesicles’ – Cavallaro – 2025 – Journal of Extracellular Vesicles – Wiley Online Library and find the Stott lab here.”
Title: Signal Amplification for Fluorescent Staining of Single Particles in Liquid Biopsies: Circulating Tumour Cells and Extracellular Vesicles
Authors: Sara Cavallaro, Sara I. Veiga, Raheel Ahmad, Berent Aldikacti, Mollie Bienstock, Diane Capen, Daniel C. Rabe, Uyen Ho, Dasol Lee, Daniel A. Ruiz-Torres, Hiroaki Wakimoto, Jorg Dietrich, Brian V. Nahed, Shannon L. Stott
Read The Full Article in Journal of Extracellular Vesicles.
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