Differences in sugar phosphate bands between normal bladder mucosa and tumoral tissue detected by Fourier transform infrared (FTIR) microreflectance spectroscopy

摘要

Fourier transform infrared spectroscopy (FTIRS) is used in cancer research, involving normal and malignant cell cultures and tissue samples. Preliminary studies have been made by some of us using ATR technique with the aid of silver halide MIR fibers. In the present work parallel preliminary results are presented concerning microreflectance technique. We studied bladder tissue in three patients. Cell clusters were obtained by mechanical apposition on an AgCl window of surgical samples of two patients. Cancer tissue and normal mucosa specimens obtained from the third patient were sliced by a scalpel and immediately relied upon ZnSe window. Diagnosis was checked on a sample counterpart. A Bio-Rad FTS 40 spectrometer and attached microscope were used. We discuss only phosphate stretching bands (PSB) which have been proposed to be `cancer sensitive.' Our results show: (1) apposition samples give fairly reproducible spectra shape and PSB peak frequencies (symmetrical: 1084.6 $POM 1.9(SD) vs. 1085.1 $POM 0.6; asymmetrical: 1240.6 $POM 1.4 vs. 1242.2 $POM 1.0; all cm$+$MIN@1$/ units); (2) spectra of thick tissue slices are more complex and irregular due to the presence of occasionally strong confounding bands (in normal mucosa), and apparently shifted in frequency; (3) tissue slices exhibit a significant (p $LS 0.02) difference in the distribution of energy within the window (running Wilkoxon test) - from roughly 1080 cm$+$MIN@1$/ to 1170 cm$+$MIN@1$/ it is greater in malignant samples and vice versa from 1230 cm$+$MIN@1$/ to 1310 cm$+$MIN@1$/.