Analysis of Human Colon by Raman Spectroscopy and Imaging-Elucidation of Biochemical Changes in Carcinogenesis

• Published in: International journal of molecular sciences Vol. 20; no. 14; p. 3398
• Main Authors: Brozek-Pluska, Beata, Musial, Jacek, Kordek, Radzislaw, Abramczyk, Halina
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 10.07.2019; MDPI
• Subjects: Biomarkers; Carcinogenesis; Carcinogens; Change detection; Cholesterol; Cluster analysis; Collagen (type I); Colon; Colon - diagnostic imaging; Colon - metabolism; Colon cancer; Colonic Neoplasms - diagnosis; Colonic Neoplasms - etiology; Colonic Neoplasms - metabolism; Colorectal cancer; Conformation; Diagnosis; Endoscopy; Esters; Fatty acids; Human tissues; Humans; Image Processing, Computer-Assisted - methods; Invasiveness; Laparoscopy; Lipids; Medical diagnosis; Medical imaging; Mortality; Mucosa; Neoplasm Staging; Nucleic acids; Patients; Phosphodiesters; Polyps; Protein structure; Proteins; Raman imaging; Raman spectra; Raman spectroscopy; Real time; spectroscopic diagnostics; Spectrum analysis; Spectrum Analysis, Raman - methods; Structural proteins; Surgery; Tumors; Raman spectroscopy; spectroscopic diagnostics; Raman imaging; biomarkers; colon cancer
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms20143398

Noninvasive Raman imaging of non-fixed and unstained human colon tissues based on vibrational properties of noncancerous and cancerous samples can effectively enable the differentiation between noncancerous and tumor tissues. This work aimed to evaluate the biochemical characteristics of colon cancer and the clinical merits of multivariate Raman image and spectroscopy analysis. Tissue samples were collected during routine surgery. The non-fixed, fresh samples were used to prepare micrometer sections from the tumor mass and the tissue from the safety margins outside of the tumor mass. Adjacent sections were used for typical histological analysis. We have found that the chemical composition identified by Raman spectroscopy of the cancerous and the noncancerous colon samples is sufficiently different to distinguish pathologically changed tissue from noncancerous tissue. We present a detailed analysis of Raman spectra for the human noncancerous and cancerous colon tissue. The multivariate analysis of the intensities of lipids/proteins/carotenoids Raman peaks shows that these classes of compounds can statistically divide analyzed samples into noncancerous and pathological groups, reaffirming that Raman imaging is a powerful technique for the histochemical analysis of human tissues. Raman biomarkers based on ratios for lipids/proteins/carotenoids content were found to be the most useful biomarkers in spectroscopic diagnostics.