Phospholipid and energy metabolism of cancer cells monitored by 31P magnetic resonance spectroscopy: possible clinical significance.

31P magnetic resonance spectroscopy (MRS) has been established as an excellent noninvasive procedure for studying metabolism in cancer cells. For a full understanding of the results of in vivo MRS studies of metabolism, it is necessary to be able to conduct controlled experiments on the same intact functioning cells in a perfusion apparatus. The specific techniques used for this purpose are described, and the applications to cancer cell bioenergetics and phospholipid metabolism in drug-resistant and drug-sensitive breast cancer cells are illustrated. Spectra of the same cell line grown in a "model tumor" in natural basement membrane gel and in nude mice in vivo are compared. The results indicate a potential for the use of 31P MRS in a clinical setting for monitoring therapy and for diagnosis.