The main goal using MR Metabolomics is to evaluate the clinical value of HR MAS for different kinds of cancer (breast, brain, prostate, colon and cervix), and by that establish HR MAS for predicting metastatic potential and choice of treatment.
High-resolution magic angle spinning (HR-MAS) MR spectroscopy is an ex vivo technique that can be applied to intact tissue for obtaining a detailed picture of tissue biochemistry (describing the small molecules, metabolites, that are the building-blocks of living organisms). The HR-MAS technique reduces the chemical shift anisotropy and dipole-dipole interaction (causes broad lines) by spinning the sample at a fast rate (typically 5 kHz) and in specific angle (54.7°), resulting in tissue spectra with very narrow lines and more separated peaks.
Figure:Schematic presentation of a MAS rotor (figure by Beathe Sitter) that is fast spinning in an angle of 54.7°, which allow a MR spectrum with very narrow lines. This is an example of a breast cancer spectrum (choline region) obtained by HR-MAS (Sitter et al 2002).
Cancer tissue differs from healthy tissue in several ways, such as increased cell proliferation and degree of cell differentiation, and these processes involve chemical reactions causing an altered metabolism in cancerous tissue. The metabolic alterations in diseased tissue can be observed and quantified by HR-MAS. Our group has specialized in analyzing HR-MAS data with multivariate methods (see data analysis), but is also implementing new quantification methods such as ERETIC (Electronic REference To access In vivo Concentrations). Since HR-MAS is non-destructive to the tissue and the same sample can undergo additional histopathological, genetic or other types of analyses, the important link between pathology, biochemistry and genetics can be obtained.
Breast cancer tissue has in our group been characterized by HR MAS (Sitter et al. 2002), and MR spectroscopic description of breast cancer tissue has been found to correlate to clinical findings (Sitter et al. 2006). These findings suggest that characterization of breast cancer tissue by HR MAS can be a tool in breast cancer diagnosis, treatment regime planning and treatment monitoring. Other types of tissue that has been studied by HR MAS at our lab are cervical cancer tissue (Lyng et al 2006, Sitter et al. 2004), brain tissue (Sitter et al. 2004) and colon tissue. We have ongoing HR MAS studies on all these tissue types.
