H-1-MRS lipid signal modulation and morphological and ultrastructural changes related to tumor cell proliferation

Changes in signal intensity of H-1-MRS mobile lipids, mostly triglycerides, have been observed in cultured HeLa cells during exponential growth. Signa ls were intense in the first days after seeding and almost disappeared afte r a few days in culture. Choline-based metabolites were not affected by gro wth. Treatment with the antitumor drug lonidamine, which blocks cell prolif eration and cell progression through cycle, increased lipid signal intensit y. Morphological changes in the organization of the cell surface were detec ted by scanning electron microscopy during exponential growth, and were con firmed by freeze fracture analysis. The observed metabolic and structural m odifications during cell growth were correlated to cell cycle progression o f HeLa cells, as high-intensity lipid signals were typical of cells with a high percentage of S- and G(2) + M-phases, while cells with a high frequenc y in G(1)-phase were characterized by mobile lipid signals of very low inte nsity. Magn Reson Med 42:248-257, 1999. (C) 1999 Wiley-Liss, Inc.