Evaluation of several methodological challenges in circulating miRNA qPCR studies in patients with head and neck cancer

Standardizing methods for collecting circulating microRNAs (ci-miRNAs) could help develop useful biomarkers for cancer. Certain ci-miRNAs, short non-coding RNA sequences, become more abundant when tumors develop. These molecules are attractive biomarkers because they can be measured in blood samples, which are minimally invasive to collect; however, results have shown poor reproducibility between studies. Dennis Poel and co-workers at the VU University Medical Center in Amsterdam, The Netherlands, investigated why the markers show so much variability. Analysis of blood samples from healthy individuals and patients with head and neck cancer showed consistent ci-miRNA levels for each patient over time, with differences in collection and analysis methods causing most of the inconsistency. Among other recommendations for standardization, the researchers recommend using a non-human miRNA as a control, and processing samples within four hours of collection.