Lower levels of 1H MRS-visible mobile lipids in H-ras transformed tumorigenic fibroblasts with respect to their untransformed parental cells.
High resolution 1H MRS studies report increased mobile neutral lipid (MNL) signals in transformed and malignant as well as in some in vitro cultured embryonic cells. Nature, subcellular localization and biological function of MNL are still under debate. This work was aimed at assessing alterations induced in MNL signals of NIH-3T3 mouse embryo fibroblasts by transformation with human HJ-ras oncogene. Lower MRS-visible MNL levels were unexpectedly detected in ras-transformed, in vivo tumorigenic fibroblasts, with respect to their untransformed and non-tumorigenic parental cells. MRS, gas chromatography and chemical analysis on cells and their lipid extracts indicated that these spectral differences could hardly be attributed to different triacylglycerol, free fatty acids and total cholesterol levels or to changes in the fatty acyl degree of unsaturation and average chain length. Additional, possibly more relevant mechanisms of regulation of MNL mobility may implicate the extensive morphogenetic changes and reorganization of cytoskeleton components (notably actin) associated with ras-transformation.
Knijn
A
A
Laboratory of Cell Biology, Istituto Superiore di Sanità, Roma, Italy.
Ferretti
A
A
Zhang
P J
PJ
Giambenedetti
M
M
Molinari
A
A
Meschini
S
S
Pulciani
S
S
Podo
F
F
D000818:Animals; D002471:Cell Transformation, Neoplastic / Q000235:genetics*; D002784:Cholesterol / Q000032:analysis / Q000737:chemistry; D005227:Fatty Acids / Q000032:analysis / Q000378:metabolism; D005347:Fibroblasts / Q000737:chemistry / Q000378:metabolism / Q000473:pathology; D011905:Genes, ras; D006801:Humans; D050356:Lipid Metabolism; D008055:Lipids / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D051379:Mice; D014280:Triglycerides / Q000032:analysis; D014316:Tritium
D005227:Fatty Acids; D008055:Lipids; D014280:Triglycerides; D014316:Tritium; D002784:Cholesterol