Fourier transform infrared spectroscopy for the distinction of MCF-7 cells treated with different concentrations of 5-fluorouracil

Background: In order to provide personalized treatment to patients with breast cancer, an accurate, reliable and cost-efficient analytical technique is needed for drug screening and evaluation of tumor response to chemotherapy. Methods: Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) was used as a tool to assess cancer cell response to chemotherapy. MCF-7 cells (human breast adenocarcinoma cell line) were treated with different concentrations of 5-fluorouracil (5-FU). The inhibition of cell proliferation was monitored by MTT, and apoptosis rates were determined by flow cytometry. Finally, spectra of the cell populations were acquired by ATR-FTIR. Results: The cell response to 5-FU was detectable at different concentrations by ATR-FTIR. First, a band observed at 1741 cm(-1), representing membrane phospholipids, was enhanced with increasing 5-FU concentrations. In addition, the MCF-7 cell spectrum shifted progressively from 1153 to 1170 cm(-1) with increasing drug doses. Finally, the normalized band intensity of 1741 cm(-1)/Amide I was highly correlated with the percentage of apoptotic cells as assessed by partial correlation analysis. Conclusions: These findings suggest that the effects of different concentrations of drugs can be monitored by ATR-FTIR, which may help evaluate the response to chemotherapy and improve treatment strategies.