Common Raman Spectral Markers among Different Tissues for Cancer Detection

Abstract

Introduction <br/>Raman spectroscopy is a vibrational spectroscopic technique, based on inelastic scattering of monochromatic light. This technique can provide valuable information about biomolecular changes, associated with neoplastic transformation. The purpose of this study was to find Raman spectral markers for distinguishing normal samples from cancerous ones in different tissues. <br/>Materials and Methods <br/>Ten tissue samples from the breast, colon, pancreas, and thyroid were collected. A Raman system was used for Raman spectroscopic measurement of tissues at 532 nm laser excitation. Five to six Raman spectra were acquired from each sample (a total of 52 spectra). Raman spectra were investigated in important bands associated with Amid1, CH2 (scissoring), Amid3, d(NH), n(C-C), and d_as (CH3) in both normal and cancerous groups. In addition, common spectral markers, which discriminated between normal and cancerous samples in the above tissues, were investigated. <br/>Results <br/>Common spectral markers among different tissues included intensities of Amid3 and CH2 (scissoring) and intensity ratios of I(Amid1)/I(CH2), I(n(C-C))/I(CH2), and I(d(NH))/I(CH2). This study showed that Amid1-, n(C-C)-, and d(NH)-to-CH₂ intensity ratios can discriminate between normal and cancerous samples, with an accuracy of 84.6%, 82.7%, and 82.7% in all studied tissues, respectively. <br/>Conclusion <br/>This study demonstrates the presence of common spectral markers, associated with neoplastic changes, among different tissues.