The Saliva Test to Detect Mouth and Throat Cancer
A new non-invasive method to detect the presence of human papilloma virus (HPV)-16 in saliva has been successfully used in a collaboration between Duke University, UCLA, and University of Birmingham. HPV-16 is a high-risk virus known to be an etiologic agent for the development of head and neck cancers, specifically with oropharyngeal caners (OPCs). Cancers in these regions often do not get diagnosed until they become advanced, which is mainly due to their location making it difficult to see during routine clinical exams.
Published in the Journal of Molecular Diagnostics, the researchers used a technique called acoustofluidic exome isolation to detect HPV-16 in saliva which could provide faster and more accurate methods for detection.
HPV-16 driven oropharyngeal cancers are one of the fastest-rising cancers in Western countries, especially in younger patients, with 115,000 cases per year worldwide. This cancer usually responds well to treatment with a disease-free survival rate of 85-90%, however early detection is difficult.
The new technology uses acoustofluidics, a method that fuses acoustics and microfluidics, that can separate biological targets with acoustic waves ranging from tens of nanometres to several hundred micrometres in size. It detects exomes that are packaged with HPV-associated biomarkers and isolates them from the saliva. It’s analysed using a tiny acoustofluidic chip (the size of a 2p coin) and filters all the particles by size, leaving exome-rich concentrated samples to allow detection of biomarkers easily.
The saliva of 10 patients already diagnosed with HPV-driven OPC using traditional methods was used. The researchers found that the acoustofluidic chip detected HPV-16 DNA in 80% of the cases when coupled together with droplet digit PCR at a speed of five minutes. As well as being very fast, the method can also be run at low cost and points of care, and is suitable to continuously monitor tumour progression in patients, unlike traditional invasive biopsy.
The researchers believe this technique is ideal for clinical settings because the technology is independent of sample variability between patients, such as saliva viscosity and collection methods used.
This technology is not only limited to saliva, and can be used to analyse other biofluids such as blood, urine, and plasma. Acoustofluidic technology has the potential to aid in the discovery of new tumour biomarkers and exceed current industry standards, as well as detecting HPV-driven cancers before they become too advanced.