Duke University, UCLA and the University of Birmingham (IUK) led a compelling international collaboration leading to a breakthrough in mouth and throat cancer. They team has developed a new non-invasive method that analyzes saliva for the presence of human papilloma virus (HPV)-16, the pathogenic strain associated with oropharyngeal cancers (OPCs). This novel technique detected OPC In whole saliva in 40% of patients tested and 80% of confirmed OPC patients.
Cancers of the throat and back of mouth are difficult to diagnose early on, leaving them undiagnosed until they become advanced. This is, in part, because their location makes them difficult to detect during routine clinical exams. But it represents a more dangerous situation for patients as the disease is now typically more advanced.
With 115,000 worldwide cases of OPC per year, it is one of the fastest growing cancers in Western societies, possibly relating to an increase in HPV-related incidence. This trend appears more pronounced with younger patients. The study team sought to find novel ways to accelerate new surveillance and detection methods to help physicians predict which patients will respond best to radiation therapy or ultimately achieve a lengthier profession-free survival.
Unfortunately, cancers that occur in the back of the mouth and upper throat are often not diagnosed until they become advanced, partly because their location makes them difficult to see during routine clinical exams.
The Intellectual Property
The multi-site team was able to leverage an acoustofluidic platform, which allowed them to separate and isolate salivary exomes. The study results follow below but first we provide an introduction to Exomes.
What are Exomes?
Exosomes are tiny microvesicles originating within cells that are secreted into body fluids. They are believed to play a role in intercellular communication and their numbers are elevated in association with several types of cancers. Acoustofluidics is an advanced technology that fuses acoustics and microfluidics. Fluid samples are analyzed using a tiny acoustofluidic chip developed to isolate salivary exosomes by removing unwanted particles based on size, leaving exosome-rich concentrated samples that make it easier to detect tumor-specific biomarkers.
Published in Elsevier’s the Journal of Molecular Diagnostics, the investigators analyzed saliva samples from 10 patients diagnosed with HPV-OPC using traditional methods. They found that the technique identified the tumor biomarker HPV-16 DNA in 80 percent of the cases when coupled with droplet digit PCR. Since this method is independent of sample variability that arises due to changes in saliva viscosity and collection methods used, it may prove ideal for use in clinical settings.
Dr. Tony Jun Huang, one of the investigators from Duke, highlighted some of the technique’s features, including automated and fast exosome isolation (less than five minutes of processing time compared to approximately eight hours of processing time using benchmark technologies). Analyses can be performed at a relatively low cost and at points of care. Also, it is suitable for repeated and continuous monitoring of tumor progression and treatment, unlike traditional biopsy.
Prof. Hisham Mehanna, Director of the Institute of Head and Neck Studies and Education, University of Birmingham, UK
Tony Jun Huang, PhD, Department of Mechanical Engineering and Materials Science, Duke University