Surface-enhanced Raman spectroscopy in liquid biopsy for breast cancer

Despite current large-scale mammography screening programmes, breast cancer is still the leading cause of cancer death in women in the vast majority of countries. It is recognizable that cancer deaths could be prevented through earlier diagnosis and adequate treatment. Therefore, new vigilant diagnostic tools that could provide an earlier diagnostic should be developed. The progress regarding sensitive, robust, fast, and cost-effective biosensors is a very active research field. Surface-enhanced Raman scattering (SERS) spectroscopy is a powerful technique for ultrasensitive label-free analysis of chemical and biological samples with wide applicability, vastly demonstrated for cancer. Nevertheless, translation of SERS to the clinics and industry is limited due to the lack of reproducible substrates and automation routines to analyze complex spectra. Liquid biopsy is the most commonly used practice for clinical preliminary disease screening. Some groups have already shown noteworthy work addressing the potential of SERS in blood plasma and urine, making it suitable for rapid and minimally invasive cancer diagnosis. SERS can be applied to sense subtle changes in composition and structure of biomolecules in plasma/urine from cancer subjects. Allied to this, discriminant analysis models (DAM) have been applied to SERS. These studies demonstrate that a powerful diagnostic system can be built for cancer screening with very high specificity and sensitivity.The main objective of SIREN is the development of a liquid biopsy test on which highly sensitive solid SERS substrates will detect changes in biomolecular profile between cancer and no cancer samples. Blood plasma and serum, and urine will be used in a label-free detection. Combining with new developed clinical decision-support systems based on SERS spectral analysis the project will provide a classification system for early diagnosis progression and breast cancer in patients.