The Detection of Apoptosis Levels in 5-FU treated Cholangiocarcinoma Tissues using Fourier Transform Infrared (FTIR) Microspectroscopy

Abstract

Cholangiocarcinoma (CCA) is an epithelial bile duct cancer which is found mostly in the northeast of Thailand. CCA patients have a low rate of survival due to delayed diagnosis and poor responses to chemotherapeutic drugs. Thus, drug response screening is expected to improve the clinical outcome. Recently, Fourier Transform Infrared (FTIR) microspectroscopy is a potential tool for molecular changed detection in cells and tissues. Therefore, this study aimed to classify the chemotherapeutic responses in 8 CCA tissues by using Conventional-FTIR microspectroscopy. Tissue biopsies from CCA patients were cultured with 200 µM of 5-FU. Samples were paraffin embedded and sectioned into two pieces for, first, TUNEL staining to count apoptotic cells and calculate drug response as a % inhibitory index (%II) and, second, FTIR measurement. Principal Component Analysis (PCA) was performed after FTIR experiment to classify the group of apoptotic levels. The results showed that FTIR microspectroscopy could distinguish resistant samples from a set of sensitive samples. In particular, we observed changes of bands at 1621 cm^-1 in resistant samples shift to 1639 cm^-1 in sensitive samples which is associated to the process of cell apoptosis. This approach is proposed as a rapid method for the apoptotic cell detection in chemotherapeutic response of CCA tissues before treatment. The correlation between the IR spectral signature and various % II should be evaluated in more samples in further study.