Nanostructured Integrated Circuits detect Type and Severity of Cancer

The analysis of panels of nucleic acid biomarkers offers valuable diagnostic and prognostic information for cancer management. Scientists at University of Toronto published a recent article in ACSNano where they reported a chip onto which they integrated novel nanostructured microelectrodes and with which direct detection of cancer biomarkers in heterogeneous biological samples—both cell extracts and tumor tissues is possible. Coarse photolithographic microfabrication defines a multiplexed sensing array; bottom-up fabrication of nanostructured microelectrodes then provides sensing elements. They have analyzed a panel of mRNA samples for prostate cancer related gene fusions using the chip. Gene fusions were identified which can correlate with aggressive prostate cancer and distinguished these from fusions associated with slower-progressing forms of the disease.

The multiplexed nanostructured microelectrode integrated circuit reported provides direct, amplification-free, sample-to-answer in under 1 h using the 10 ng of mRNA readily available in biopsy samples. The detection platform described in this research is not only specific, sensitive, and robust, but it is also practical and scalable. The reproducible fabrication method chosen is amenable to the production of probe-modified chips using the same photolithographic technologies in widespread use in consumer electronics microchip fabrication, and only simple, inexpensive instrumentation is needed for readout. Microfluidics are not required for automated analysis, as hybridization can be performed and read out in a single reaction vessel. This system represents an attractive alternative to PCR-based methods that are sensitive but difficult to automate in a clinical setting.

In summary, the new multiplexed electrode platform suggested in the paper is the first to read directly a panel of cancer biomarkers in clinically relevant samples using electronic signals. The array enabling these measurements features microelectrodes that possess controllable and versatile nanotexturing essential for sensitivity. The system combines these nanotextured electrodes with rapid catalytic readout to achieve a long-standing goal: the multiplexed analysis of cancer biomarkers using an inexpensive and practical platform.