Corporate Banner
Satellite Banner
Scientific Community
Become a Member | Sign in
Home>News>This Article

Droplet Digital PCR Enables Measurement of Potential Cancer Survival Biomarker

Published: Tuesday, December 10, 2013
Last Updated: Tuesday, December 10, 2013
Bookmark and Share
Study paves the way for further research into the role of TIL quantification in immunotherapy and as a cancer survival predictor.

Researchers at Fred Hutchinson Cancer Research Center have used Droplet Digital PCR (ddPCR™) to demonstrate for the first time the quantification of a special class of tumor-attacking immune cell known to improve cancer survival, a subpopulation of T-cells called tumor-infiltrating T-lymphocytes or TILs. The study, led by Dr. Jason Bielas, Associate Member of the Public Health Sciences Division at Fred Hutch, paves the way for further study of the role of TIL quantification in immunotherapy and as a cancer survival predictor.

"Now that we have the sensitivity and ability to reproducibly count TILs in tumors, we may be able to stratify and more effectively treat patients based on tumor TIL count, especially with immunotherapeutics coming to market," said Dr. Bielas, one of the lead authors of a paper reporting the TIL quantification results in Science Translational Medicine.

Quantifying TILs Using ddPCR
TILs directly attack tumor cells in a variety of cancer types. While the presence and quantity of TILs strongly correlate with increased patient survival, current tests are semiquantitative at best. As a result, TILs cannot be used for clinical decision making.

According to Dr. Bielas, TILs have a "genomic signature that can be digitally exploited." This signature, which exhibits a vast amount of diversity, determines the genetic identity, or clonality, of the T-cell receptors (TCR) expressed on the surface of each TIL. With the advent of digital PCR – and the generation of tens of thousands of data points produced by Droplet Digital PCR – it is now possible to quantify these signatures, enabling the determination of the number of TILs.

"There's no way you could do this with any method other than digital PCR because of the numerous primer pairs and probes that we have (45 forward primers, 13 reverse primers, and 30 probes)," said Dr. Bielas. "Digital PCR partitions all the reactions so you can amplify these targets independently of PCR efficiency without any competing side reactions."

Fred Hutch researchers developed the Droplet Digital PCR-based "QuanTILfy" assay using Bio-Rad Laboratories' QX100 ddPCR system. They then used QuanTILfy to count TILs, determine their frequency, and develop a grouping system to classify "clonality," which might be a marker of druggable targets.

Study Results
Fred Hutch researchers performed the QuanTILfy assay on primary tumors from 30 ovarian carcinoma patients with known survival outcomes, ranging from 1 to 122 months. TIL frequency was approximately threefold higher in patients with a survival rate of more than five years compared with patients with survival rates of less than two years. These results show that higher TIL levels correlate positively with patient survival, consistent with the hypothesis that TILs play an active role in suppressing tumor formation.

The researchers also demonstrated that QuanTILfy can be used to accurately and reproducibly characterize T-cell clonality in patients with T-cell acute lymphoblastic leukemia. In each case, they saw a single QuanTILfy assay subgroup, indicative of clonal T-cell expansion. This finding was confirmed by deep sequencing.

The QuanTILfy assay proved to be both sensitive and accurate. In a mixture of human T-cells purified from blood and normal human lung fibroblasts, the assay demonstrated the ability to detect a single TCR rearrangement among 10,000 tumor cells. Importantly, it also demonstrated the ability of ddPCR technology to quantify a large number of markers simultaneously in a single reaction through multiplexing.

Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,800+ scientific posters on ePosters
  • More than 4,000+ scientific videos on LabTube
  • 35 community eNewsletters

Sign In

Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Awards for Bio-Rad's Protein Expression Products and Genomic Workflow Solutions
BioInformatics LLC has recognized Bio-Rad with two prestigious Life Science Industry Awards for “Best Protein Expression & Analysis Products” and “Best Workflow Solutions — Genomics.”
Monday, January 19, 2015
A Brief RT-qPCR “Field Guide” for MIQE Adherence
Bio-Rad’s Sean Taylor and Eli Mrkusich have published a practical guide for MIQE compliance.
Monday, December 09, 2013
Accurate Detection of Extremely Rare Mitochondrial DNA Deletions Associated with Aging
The study published in Aging Cell identifies a new tool to accurately analyze extremely rare mitochondrial DNA deletions associated with a range of diseases and disorders as well as aging.
Thursday, September 05, 2013
Bio-Rad Announces Mini-Protean Tetra Cell Users Website
The new online social networking site is created for current and new Bio-Rad Mini-PROTEAN® system users.
Wednesday, August 20, 2008
Bio-Rad Launches new Website for Researchers Transfecting Mammalian Cells
Bio-Rad adds ‘Gene Transfer Protocols’ to its Gene Expression Gateway Web-site, dedicated to researchers working with mammalian cells.
Friday, June 27, 2008
Testing Results of the BioOdyssey Calligrapher MiniArrayer for Clinical Research Available
Bio-Rad announces the availability of a technical bulletin describing results of the testing of the BioOdyssey™ Calligrapher™ MiniArrayer.
Thursday, November 08, 2007
Scientific News
New Tech Vastly Improves CRISPR/Cas9 Accuracy
A new CRISPR/Cas9 technology developed by scientists at UMass Medical School is precise enough to surgically edit DNA at nearly any genomic location, while avoiding potentially harmful off-target changes typically seen in standard CRISPR gene editing techniques.
New Class of RNA Tumor Suppressors Identified
Two short, “housekeeping” RNA molecules block cancer growth by binding to an important cancer-associated protein called KRAS. More than a quarter of all human cancers are missing these RNAs.
Biologists Induce Flatworms to Grow Heads and Brains of Other Species
Findings shed light on role of a new kind of epigenetic signaling in evolution, could yield clues for understanding birth defects and regeneration.
Turning up the Tap on Microbes Leads to Better Protein Patenting
Mining millions of proteins could become faster and easier with a new technique that may also transform the enzyme-catalyst industry, according to University of California, Davis, researchers.
Mathematical Model Forecasts the Path of Breast Cancer
Chances of survival depend on which organs breast cancer tumors colonize first.
Exploring the Causes of Cancer
Queen's research to understand the regulation of a cell surface protein involved in cancer.
Ancient Viral Molecules Essential for Human Development
Genetic material from ancient viral infections is critical to human development, according to researchers at the Stanford University School of Medicine.
Tardigrade's Are DNA Master Thieves
Tardigrades, nearly microscopic animals that can survive the harshest of environments, including outer space, hold the record for the animal that has the most foreign DNA.
The Secret Behind the Power of Bacterial Sex
Migration between different communities of bacteria is the key to the type of gene transfer that can lead to the spread of traits such as antibiotic resistance, according to researchers at Oxford University.
Farming’s in Their DNA
Ancient genomes reveal natural selection in action.
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,800+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,000+ scientific videos