H-1-NMR SPECTROSCOPIC CHARACTERIZATION OF PERCHLORIC-ACID EXTRACTS FROM BREAST CARCINOMAS AND NONINVOLVED BREAST-TISSUE

High-resolution H-1 NMR spectra were obtained from perchloric acid ext racts of breast tumor specimens and adjacent non-involved tissue. Two- dimensional shift-correlated and homonuclear J-resolved spectroscopy w ere used to identify coupled resonances in the spectra. Chemical shift s, multiplicities and spin-spin coupling constants of several non-reso lved resonances in the one-dimensional spectra could be determined by the two-dimensional methods. Several differences in the metabolite con tent of the two types of extracts were established. The spectra of ext racts from non-involved tissue were dominated by signals from glucose and other carbohydrates, while most of the tumors had very low or no d etectable levels of glucose. High concentrations of lactate, taurine a nd succinate, an increase of the phosphocholine level, and a very low phosphocreatine level were characteristic findings in the H-1 spectra of tumor extracts. The variation in the level of myo-inositol follows the variation in glucose for the two types of tissue. Scyllo-inositol was for the first time observed in the NMR spectra from breast tissue. Uridine 5'-diphospho-N-acetylglucosamine and uridine 5'-diphospho-N-a cetylgalactosamine have been identified and there is an increased leve l of these two hexoses in the tumor tissue. These results provide insi ght into breast tumor metabolism, by simultaneously detecting a large number of metabolites and demonstrate the potential for using H-1 NMR spectroscopy for studying different metabolic pathways in breast tumor s. At the same time they provide useful information for interpretation of in vivo H-1 NMR spectra of breast tumors.