H-1 MRS MARKERS OF TUMOR-GROWTH IN INTRASPLENIC TUMOR AND LIVER METASTASIS INDUCED BY INJECTION OF HT-29 CELLS IN NUDE-MICE SPLEEN

We have characterized, by in vitro magnetic resonance spectroscopy (MR S), the metabolite pattern of perchloric acid (PCA) extracts of intras plenic tumours and hepatic metastasis, produced by intra-spleen inject ion of the human colorectal carcinoma cell line HT-29 and its metastat ic variant HT-29 MMM into nude mice. Our aim was to gain further under standing of colorectal tumour metabolism as a basis for future in vivo studies of human colon cancer by H-1 MRS. Metabolite PCA extract anal ysis showed a good reproduction of the spectral pattern observed in hu man primary colon tumours, while they were very different from the spe ctral pattern of the host tissues (spleen and liver). The main differe nces between host and tumour tissues involved taurine, phosphocholine (PC), phosphoethanolamine (PE), creatine, glycogen and glucose. Creati ne is the most promising marker to follow tumour growth because of its practical absence in the nude mice host tissues. Detection of variabl e levels of this compound and of taurine in hepatic foci in man, are s uggested as possible diagnostic markers. No correlation could be found between spectral pattern differences and the different ability to met astasize of the two HT-29 cell lines used. Furthemore, indirect eviden ce for a functional link between taurine and myo-inositol in colon tum our cells is presented. In summary, our data suggest that the nude mic e model may be a suitable system for the MRS study of the changes taki ng place in host tissues upon tumour progression. (C) 1998 John Wiley & Sons, Ltd.