Abnormal cholesterol metabolism in a malignant Ras-mutated rat fibroblast line
| Autor: | Bianca Fuhrman, Efrat Wolfovitz, Irit Maor, J.Gerald Brook |
|---|---|
| Rok vydání: | 1997 |
| Předmět: |
medicine.medical_specialty
Cholesterol Reverse cholesterol transport Biology Pathology and Forensic Medicine chemistry.chemical_compound medicine.anatomical_structure Endocrinology chemistry Downregulation and upregulation Cell culture Physiology (medical) Internal medicine HMG-CoA reductase medicine biology.protein lipids (amino acids peptides and proteins) Liver X receptor Fibroblast Lipoprotein |
| Zdroj: | Pathophysiology. 4:235-240 |
| ISSN: | 0928-4680 |
| DOI: | 10.1016/s0928-4680(97)00025-4 |
| Popis: | Some cancer patients demonstrate low levels of plasma cholesterol. This has been explained as resulting from a defect in the cholesterol feedback control in tumor cells. The objective of this study was to determine the presence of a relationship between cholesterol metabolism and regulation, and between the occurrence of mutated Ras protein activity. Total cholesterol mass in Ras-mutated rat embryo fibroblasts was 2 times less than that in control cells (non-mutated fibroblasts). Low-density lipoprotein (LDL) uptake, as determined by 125 I-labeled LDL degradation was 2-fold higher in the Ras-mutated cells. Downregulation of LDL uptake in both mutated and non-mutated cells was similar. Cholesterol synthesis in the mutated cells was lower by 50–66%, compared with non-mutated cells. There was no change in cholesterol efflux between the two cell lines. Thus, it appears that in these mutated cells, overutilization of the farnesyl pathway results in decreased accumulation of cholesterol in the cells. We suggest that a relationship between mutated Ras protein activity and cholesterol metabolism is present. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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