The Five Steps to miRNA Profiling

MicroRNAs (miRNAs) are small, non-coding RNAs that play a role in regulating cancer by acting as both tumor suppressors and oncogenes. Ranging in size from 18–25 nucleotides, miRNAs function in feedback mechanisms to regulate many cellular processes including cell proliferation, apoptosis, cell signaling and tumorigenesis (1).

Not surprisingly, dysregulation of miRNA expression can have serious repercussions. For example, miRNAs are dysregulated in almost all human cancers (1). Because of the potential to influence cancer growth and development, there is growing interest in miRNA profiling to identify possible biomarkers for cancer diagnosis or prognosis, as well as potential therapeutic targets (1).

Growing interest in miRNAs as both biomarkers of disease and therapeutic targets drives the need for fast and effective methods for miRNA profiling. Profiling miRNA targets follows a relatively simple workflow: sample selection, RNA extraction, RNA QC and quantitation, RNA profiling and data analysis (2,3). So what happens at each step?

Five steps of miRNA profiling

The Five Steps of miRNA Profiling

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The Search for Biomarkers: Beyond the Norm

Protein biomarker discovery is an area of considerable current interest in biology and medicine.
The implementation of proteomics technology in the field of protein biomarker discovery has expanded in the past few years to enable the identification of biomarkers from a variety of biological samples including cell lysates, tissue samples, serum, plasma and urine (for a review refer to Gao, J. et al. (2005) Methods. 35, 291-302).

One method utilized for the discovery of protein markers includes the use of trypsin digestion of target proteins followed by the analysis of the resulting peptide fragments by mass spectrometry. Continue reading