Plasmonic nanobiosensors for detection of microRNA cancer biomarkers in clinical samples.

MicroRNA (miRNA) play an important role in the regulation of biological processes and have demonstrated great promise as biomarkers for the early detection of various diseases, including esophageal adenocarcinoma (EAC) and Barrett’s esophagus (BE), the premalignant metaplasia associated with EAC. Herein, we demonstrate the direct detection of the esophageal cancer biomarker, miR-21, in RNA extracted from 17 endoscopic tissue biopsies using a nanophotonics technology our group has developed, termed inverse molecular sentinel (iMS) nanobiosensor, with surface-enhanced Raman scattering (SERS) detection. The potential of this label-free, homogenous biosensor for cancer diagnosis without the need for target amplification was demonstrated by discriminating esophageal cancer and Barrett’s esophagus from normal tissue with notable diagnostic accuracy. This work establishes the potential of the iMS nanobiosensors for cancer diagnostics via miRNA detection within clinical samples without the need for target amplification, validating the potential of this assay as part of a new diagnostic strategy. Combining miRNA diagnostics with nanophotonics technology will result in a paradigm shift in achieving a general molecular analysis tool that has widespread applicability for cancer research as well as detection of cancer. We anticipate the further development of this technique for future use in point-of-care testing as an alternative to histopathological diagnosis as our method provides a quickly obtained result following RNA isolation, allowing for timely treatment.