Optical spectroscopy of colon tissue and a breast cancer cell line : potential for cancer detection

Abstract

Two forms of cancer affecting a large number of individuals are breast cancer and colon cancer. In 2003, it was projected that approximately 21000 Canadians would be diagnosed with breast cancer and another 18000 would be diagnosed with colorectal cancer (Canadian Cancer Society 2003a, Canadian Cancer Society 2003b). Optical spectroscopy techniques for discerning biochemical and morphological properties have been investigated for potential in detecting these two types of cancer. Techniques based on absorption and fluorescence spectroscopy were developed and preliminary data were obtained using cancerous and normal colon tissue, and using living Actin and H1 GFP tagged MCF-7 breast cancer cells. Analysis of absorption spectra for normal and cancerous colon tissue samples revealed a shift between the two, which may suggest a potential method to distinguish between the two tissue types. Fluorescence spectroscopy and imaging were also performed on the colon tissue samples. Analysis of the spectroscopic data revealed potential methods for differentiating between tissues. Fluorescence measurements were performed with living Actin and HI GFP tagged MCF-7 breast cancer cells to investigate the value of imaging and spectroscopy under identical conditions. Various stages of mitosis and cellular movement were observed. As an extrapolation of this study some cells were irradiated with 5 Gy of Cobalt-60 gamma rays, but no differences between irradiated and non-irradiated samples were noted. These preliminary results reveal a potential application for optical diagnostic techniques, although further investigations are required.