Specificity of the Dihydroceramide Desaturase InhibitorN-[(1R,2S)-2-Hydroxy-1-hydroxymethyl-2-(2-tridecyl-1-cyclopropenyl)ethyl]octanamide (GT11) in Primary Cultured Cerebellar Neurons

Triola, Gemma; Fabriás, Gemma; Dragusin, Mihaela; Niederhausen, Lars; Broere, Roland; Llebaría, Amadeu; Echten‐Deckert, Gerhild van

doi:10.1124/mol.104.003681

Cited by 49 publications

(29 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Indeed, short-chain desaturated ceramides undergo cellular uptake, hydrolysis, and reacylation to long-chain ceramides (46), and in breast cancer cell lines [ 14 C]C6-ceramide was shown to be largely converted to glucosyl[ 14 C]C6-ceramide (47). To gain insight into the cytotoxic potential of longchain dihydroceramides, we used GT11, an inhibitor of dihydroceramide desaturase (34), in cells exposed to sphinganine, a dihydroceramide precursor (Fig. 5A and B).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

N-(4-Hydroxyphenyl)retinamide increases dihydroceramide and synergizes with dimethylsphingosine to enhance cancer cell killing

Wang

Maurer

Liu

et al. 2008

Molecular Cancer Therapeutics

108

View full text Add to dashboard Cite

Fenretinide [N-(4-hydroxyphenyl)retinamide (4-HPR)] is cytotoxic in many cancer cell types. Studies have shown that elevation of ceramide species plays a role in 4-HPR cytotoxicity. To determine 4-HPR activity in a multidrug-resistant cancer cell line as well as to study ceramide metabolism, MCF-7/AdrR cells (redesignated NCI/ADR-RES) were treated with 4-HPR and sphingolipids were analyzed. TLC analysis of cells radiolabeled with [ 3 H]palmitic acid showed that 4-HPR elicited a doseresponsive increase in radioactivity migrating in the ceramide region of the chromatogram and a decrease in cell viability. Results from liquid chromatography/ electrospray tandem mass spectrometry revealed large elevations in dihydroceramides (N-acylsphinganines), but not desaturated ceramides, and large increases in complex dihydrosphingolipids (dihydrosphingomyelins, monohexosyldihydroceramides), sphinganine, and sphinganine 1-phosphate. To test the hypothesis that elevation of sphinganine participates in the cytotoxicity of 4-HPR, cells were treated with the sphingosine kinase inhibitor D-erythro-N,N -dimethylsphingosine (DMS), with and without 4-HPR. After 24 h, the 4-HPR/DMS combination caused a 9-fold increase in sphinganine that was sustained through +48 hours, decreased sphinganine 1-phosphate, and increased cytotoxicity. Increased dihydrosphingolipids and sphinganine were also found in HL-60 leukemia cells and HT-29 colon cancer cells treated with 4-HPR. The 4-HPR/DMS combination elicited increased apoptosis in all three cell lines. We propose that a mechanism of 4-HPR -induced cytotoxicity involves increases in dihydrosphingolipids, and that the synergy between 4-HPR and DMS is associated with large increases in cellular sphinganine. These studies suggest that enhanced clinical efficacy of 4-HPR may be realized through regimens containing agents that modulate sphingoid base metabolism. [Mol Cancer Ther 2008;7(9):2967 -76]

show abstract

Section: Discussionmentioning

confidence: 99%

“…1). Interestingly, the addition of GT11, a dihydroceramide desaturase inhibitor (34), which mimicked the effect of 4-HPR on dihydroceramide desaturase, enhanced sphinganine cytotoxicity (Fig. 5A).…”

Section: -Hpr Increases Dihydroceramidementioning

confidence: 95%

N-(4-Hydroxyphenyl)retinamide increases dihydroceramide and synergizes with dimethylsphingosine to enhance cancer cell killing

Wang

Maurer

Liu

et al. 2008

Molecular Cancer Therapeutics

108

View full text Add to dashboard Cite

show abstract

“…Thus, SPL can be considered an emerging target for immunomodulatory therapy. Known SPL inhibitors include FTY720, 2-acetyl-4-tetrahydroxybutylimidazole, pyridoxal phosphate analogs, and the ceramide desaturase inhibitor GT11, but these agents are neither potent nor specific SPL inhibitors, and the identification of better inhibitors would be desirable (7,8,21,31).…”

Section: Discussionmentioning

confidence: 99%

A rapid fluorescence assay for sphingosine-1-phosphate lyase enzyme activity

Bandhuvula¹,

Fyrst²,

Saba³

2007

Journal of Lipid Research

View full text Add to dashboard Cite

Sphingosine-1-phosphate (S1P) lyase (SPL) catalyzes the conversion of S1P to ethanolamine phosphate and hexadecenal. This enzyme plays diverse roles in physiology and disease and, thus, may be useful as a disease marker and/or drug target. Unfortunately, the radioisotope-based assay currently used to quantify SPL activity is suboptimal. We have devised an assay using a commercially available v (7-nitro-2-1,3-benzoxadiazol-4-yl)-D-erythro (NBD)-labeled fluorescent substrate. Alternatively, we provide a method for synthesis of the substrate from NBD-sphingosine. Enzyme activity is determined by following the formation of NBD-aldehyde product, which is isolated from unreacted substrate by lipid extraction and quantified after separation by HPLC using a C18 column. A fluorescent NBD-C18-sphingosine internal standard is used to control for extraction efficiency. The reaction is linear over 20 min and total protein concentrations of 20-200 mg/l. The sensitivity of the fluorescence assay is comparable to or better than that of the radioactive assay, and SPL levels as low as 8 pmol/mg/min were readily detected. Semicarbazide, a nonspecific SPL inhibitor, reduced SPL activity in vitro by ?70% using both standard and fluorescence methods. Product inhibition was not observed using ethanolamine phosphate and a commercially available source of hexadecenal.This method is suitable for quantifying SPL activity in a variety of cell and tissue sources.-Bandhuvula, P., H. Fyrst, and J. D. Saba. A rapid fluorescence assay for sphingosine-1-phosphate lyase enzyme activity. J. Lipid Res.

show abstract

“…At higher concentrations, GT11 loses its specificity where it also inhibits serine palmitoyl transferase in cells but not in vitro. In addition, it inhibits sphingosine lyase activity contributing to sphingosine-1-phosphate accumulation (Triola et al, 2004). Together, these data indicate that the enzyme dihydroceramide desaturase may be a direct target for chemotherapeutic agents and exploring the type of bonds in enzyme-inhibitor complex could be of further interest.…”

Section: Direct Acting Agents: Retinoids and Ceramide Analoguesmentioning

confidence: 98%