Applications of magnetic resonance in model systems: Tumor biology and physiology

A solid tumor presents a unique challenge as a system in which the dynamics of the relationship between vascularization, the physiological environment and metabolism are continually changing with growth and following treatmen t. Magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MR S) studies have demonstrated quantifiable linkages between the physiologica l environment, angiogenesis, vascularization and metabolism of tumors. The dynamics between these parameters continually change with tumor aggressiven ess, tumor growth and during therapy and each of these can be monitored lon gitudinally, quantitatively and non-invasively with MRI and MRS. An importa nt aspect of MRI and MRS studies is that techniques and findings are easily translated between systems. Hence, pre-clinical studies using cultured cel ls or experimental animals have a high connectivity to potential clinical u tility. In the following review, leaders in the field of MR studies of basi c tumor physiology using pre-clinical models have contributed individual se ctions according to their expertise and outlook. The following review is a cogent and timely overview of the current capabilities and state-of-the-art of MRI and MRS as applied to experimental cancers. A companion review deal s with the application of MR methods to anticancer therapy.