Normal and Malignant Human Colonic Tissues Investigated by Pressure-Tuning FT-IR Spectroscopy

Infrared spectra of the epithelial, the connective, the mucosa, and the malignant tissues of the human colon have been measured as a function of pressure. Infrared spectra of collagen proteins have also been measured and compared with the connective tissue. The infrared spectra of different types of colon tissues exhibit significantly different patterns. With these specific infrared patterns, the tissue types of the colon can be differentiated unambiguously. Many structural changes at the molecular level from normal epithelium to malignant tumor have been derived from the spectral features of these two related tissues. These structural changes in carcinogenesis of the colon are comparable with those in other human cancers. The present results suggest that determination of these infrared spectra may be applied to the rapid identification of normal tissue types of the colon and evaluation of colon cancer.