Correlation of cellular differentiation in human colorectal carcinoma and adenoma cell lines with metabolite profiles determined by ¹H magnetic resonance spectroscopy

Abstract

The aim was to determine whether proton magnetic resonance spectroscopy (MRS) could grade human colorectal cells of differing malignant potential. A cell model of tumour development and progression comprising 2 non-tumorigenic adenoma lines and 4 carcinoma lines of increasing tumorigenicity was chosen. A gradual reduction in cellular differentiation and an accumulation of genetic alterations from adenoma to carcinoma characterized the selected cell lines. One-dimensional and 2-dimensional MRS showed that reduced differentiation in the cell model correlated with an increase in the levels of lipid, metabolites, the glycosylation intermediate uridine diphospho-N-acetylglucosamine and cell-surface fucosylation. Mutations involving the K-ras, APC and DCC genes are present both in adenoma- and in carcinoma-derived lines in this model, but the first evidence of an abnormality in the p53 gene was concomitant with the cells' ability to grow as a tumour in athymic nude mice. This genetic change coincided with the detection, by MRS, of UDP-hexose (ribose moiety, 2D MRS cross peak between H2 at 4.38 ppm and HI at 5.99 ppm) and the appearance of an additional fucosyl resonance (cross peak between-CH3 at 1.41 and H5 at 4.30 ppm) in the least tumorigenic of the carcinoma cell lines. An increase in complexity of the fucosylation spectral pattern was observed with further cellular de-differentiation and increased tumorigenicity. Collectively these data support the existence of an adenoma-carcinoma sequence.

Metabolomics by Proton Nuclear Magnetic Resonance Spectroscopy of the Response to Chloroethylnitrosourea Reveals Drug Efficacy and Tumor Adaptive Metabolic Pathways

“…The used differential metabolomics technique involving quantitative two-dimensional proton NMR spectroscopy was innovative among the other proposed quantification procedures (6,7,13,17,25,26). Because correlation signals in two-dimensional proton NMR spectroscopy are all variably related to concentration (19) and because no standardization of the signal has emerged, it remains a major aim in metabolomics to develop novel quantitative procedures.…”

“…Both cross-peaks were broad signals, wider than those of fatty acid correlations and those of fucose (17). The lysyl resonance is frequent in one-dimensional NMR…”

1H-NMR detectable fatty acyl chain unsaturation in excised leiomyosarcoma correlate with grade and mitotic activity.

“…Resonance assignments were based on previously published chemical shift values and spin-spin coupling patterns (20) and TOCSY spectra of phosphocholine, glycerophosphocholine, choline, phosphoethanolmine, N -acetylgalactosamine, galactose, triolein, and fatty acids recorded by us at 600 MHz. The cross-peaks assigned to C and D in our TOCSY spectra of linoleic, linolenic and arachidonic acid in chloroform all possess the same chemical shifts.…”

Quantitative HRMAS proton total correlation spectroscopy applied to cultured melanoma cells treated by chloroethyl nitrosourea: Demonstration of phospholipid metabolism alterations

“…In the field of cancer, and among homonuclear 2D spectroscopy sequences, proton COSY had enabled the quantification of relative concentrations of some Plp derivatives and other species from perchloric acid extracts of colon carcinoma (19). COSY has also been used to obtain fucose:Cho ratios in several cancer cell lines (20). However, most authors acknowledge the superiority of TOCSY as applied to heterogeneous biological material, because of its increased sensitivity, ability to elicit long-range correlations, and pure absorption mode of cross-peaks (21,22).…”