Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lovastatin, an inhibitor of 3-hydroxy-3-methylglutaryl (HMG) CoA reductase, and 6-fluoromevalonate (Fmev), an inhibitor of diphosphomevalonate decarboxylase, blocked the synthesis of downstream mevalonate products, including prenyl-derived lipids, and prevented membrane localization of Ras in the myeloid cell line U-937. In contrast to lovastatin, which induced cytosol localization of Ras in U-937 cells, Fmev failed to increase cytosolic Ras and also completely prevented the proliferation of U-937 cells. Growth of U-937 cells was restored by the addition of lovastatin to Fmev-blocked cells. These results implied that a product of mevalonate metabolism proximal to isopentenyl diphosphate was responsible for the suppression of proliferation. To delineate the action of this endogenous inhibitor of cell proliferation and determine the relationship between its impact on Ras localization and cell proliferation, the effect of Fmev on a variety of leukemia- and lymphoma-derived cells was examined. Whereas Fmev blocked the growth of these cell lines, there were more than 50-fold differences in the concentrations required to inhibit the growth of individual cell lines by 90%. Regardless of its effect on cell proliferation, the biochemical effect of Fmev was similar. Thus, Fmev uniformly prevented the conversion of radiolabeled mevalonate to isopentenyl diphosphate and other downstream products, including synthesis of sterol and nonsterol lipids and prenylation of proteins. A correlation was noted between higher intrinsic rates of mevalonate synthesis by a cell and susceptibility to inhibition by Fmev. Thus, sensitivity of a cell line to inhibition by Fmev was associated with markedly increased rates of HMG CoA reductase activity that were further increased by incubation with Fmev. Whereas Fmev depleted cellular levels of the prenylated protein Ras in the sensitive cell line U-937, there was no depletion of cellular Ras levels in the resistant cell line EL-4, but rather, there was a shift of Ras from membrane to cytosol, as expected for inhibition of prenylation. These results suggest that leukemic cells with increased HMG CoA reductase activity produce increased levels of an endogenous mevalonate-derived inhibitor that leads to Ras depletion and suppression of cell growth. As a result, inhibition of the growth of these transformed cells might be specifically accomplished by Fmev.
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PMID:Regulation of proliferation and Ras localization in transformed cells by products of mevalonate metabolism. 927 19

Two new prenylated flavones, named artoindonesianin A (1) and artoindonesianin B (2), were isolated from the root of Artocarpus champeden, together with a known prenylated flavone, artonin A. The structures of artoindonesianins A and B were determined on the basis of spectral evidence (MS, 1H and 13C NMR) and by comparison with known related compounds. Compounds 1 and 2 exhibited cytotoxic activity against murine leukemia (P-388) cells.
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PMID:Artoindonesianins A and B, two new prenylated flavones from the root of Artocarpus champeden. 1021 22

Eleven known compounds and a new prenylated naphthoquinone, lippsidoquinone (13), were isolated from ethanol extracts of Lippia sidoides. Their structures were established by a combination of 1D and 2D NMR, IR, and EIMS spectral data analysis. The cytotoxic properties of compounds 3--13 were evaluated against HL60, SW1573, and CEM cell lines. Only tectol (6) and lippsidoquinone (13) exhibited significant activity against human leukemia cell lines HL60 and CEM.
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PMID:Chemical constituents from Lippia sidoides and cytotoxic activity. 1142 46

A new prenylated flavone, named artoindonesianin L (1), was isolated from Artocarpus rotunda (Hout) Panzer (Moraceae). Its structure was elucidated as on the basis of spectroscopic evidence. Along with this new compound, four known phenolic compounds were also isolated from this plant and identified as artonins M (2) and E (3), cycloartobiloxanthone (4) and artonin O (5). All these compounds showed significant cytotoxicity against murine P388 leukemia cells.
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PMID:Artoindonesianin L, a new prenylated flavone with cytotoxic activity from Artocarpus rotunda. 1173 Nov 16

G4 and p13(II) are accessory proteins encoded by the X region of bovine leukemia virus and human T-cell leukemia virus type 1 (HTLV-1), respectively. Disruption of the G4 and p13(II) open reading frames interferes with viral spread in animal model systems, indicating that the corresponding proteins play a key role in viral replication. In addition, G4 is oncogenic in primary cell cultures and is absolutely required for efficient onset of leukemogenesis in sheep. To gain insight into the function of these proteins, we utilized the yeast two-hybrid system to identify protein partners of G4. Results revealed that G4 interacts with farnesyl pyrophosphate synthetase (FPPS), a protein involved in the mevalonate/squalene pathway and in synthesis of FPP, a substrate required for prenylation of Ras. The specificity of the interaction was verified by glutathione S-transferase (GST) pull-down assays and by coimmunoprecipitation experiments. Furthermore, confocal microscopy showed that the subcellular localization of G4 was profoundly affected by FPPS. The G4 protein itself was not prenylated, at least in rabbit reticulocyte lysate-based assays. The domain of G4 required for binding to FPPS was restricted to an amphipathic alpha-helix rich in arginine residues. Subtle mutation of this alpha-helix abrogated G4 oncogenic potential in vitro, providing a biological relevance for FPPS-G4 complex formation in cells. Finally, HTLV-1 p13(II) was also found to specifically interact with FPPS (in yeast as well as in GST pull-down assays) and to colocalize with G4 in mitochondria, suggesting a functional analogy between these oncoviral accessory proteins. Identification of FPPS as a molecular partner for p13(II) and G4 accessory proteins opens new prospects for treatment of retrovirus-induced leukemia.
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PMID:Oncoviral bovine leukemia virus G4 and human T-cell leukemia virus type 1 p13(II) accessory proteins interact with farnesyl pyrophosphate synthetase. 1177 14

A new prenylated flavone, named artoindonesianin P (1), was isolated from the tree bark of Artocarpus lanceifolius, together with three known related compounds, artobiloxanthone (2), cycloartobiloxanthone (3) and artonol B (4). The structure of artoindonesianin P 1 was determined on the basis of spectral evidence (MS, 1H and 13C NMR) and by comparison with known related compounds. Compounds 1-4 exhibited significant cytotoxicity against murine P388 leukemia cells.
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PMID:Artoindonesianin P, a new prenylated flavone with cytotoxic activity from Artocarpus lanceifolius. 1249 Feb 27

The knowledge that Ras was readily prenylated by protein FTase and that the inhibition of this reaction has the ability to revert the transformed phenotype, provided the rationale for the development of FTIs as anticancer drugs. Studies have shown that farnesylation of Ras is the first, obligatory first step in a series of post-translational modifications leading to membrane association, which, in turn, determines the switch from an inactive to an active Ras-GTP bound form. Based on the theorical assumption that preventing Ras farnesylation might result in the inhibition of Ras functions, a range of FTIs have been synthesized. Their biology is fascinating since after substantial investigation and their use in several phase II studies and at least two phase III trials, the exact mechanism of action remains unclear. FTIs can block the farnesylation of several additional proteins, such as RhoB, prelamins A and B, centromere proteins (CENP-E, CENP-F), etc. While the FTIs clearly do not or only partly target Ras, these agents appear to have clinical activity in leukemia and in some solid tumors regardless of their Ras mutational status. Although inhibition of FTase by these compounds has been well documented also in normal tissues, their toxic effects seem to be manageable. However, preliminary results of early Phase II-III studies suggest that the activity of FTIs, as a single-agent, is modest and generally lower than that obtained by standard cytotoxic drugs. Ongoing clinical studies are assessing the role of FTIs for early stage disease or in combination with cytotoxic agents or with other molecular targeted therapies for advanced stage tumors. Further insights in the molecular mechanism of action of FTIs might help in better define their optimal use in combination with standard therapies in the treatment of cancer patients.
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PMID:Farnesylated proteins as anticancer drug targets: from laboratory to the clinic. 1503 18

Opopanax chironium is a rich source of furano- and dihydrofuranocoumarins, whose accumulation in all plant parts and especially the roots is presumably responsible for the poisonous properties of the species. The presence of two distinct chemotypes was evidenced, with the one from Sicily affording the new dihydrofuranocoumarins 5d and 5e, while extracts from the Sardinian chemotype showed powerful apoptotic activity, which was traced to the prenylated furanocoumarins heraclenin (2a) and imperatorin (2b). Despite a close structural similarity, compounds 2a and 2b induced apoptosis in Jurkat leukemia cells in mechanistically different ways.
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PMID:Coumarins from Opopanax chironium. New dihydrofuranocoumarins and differential induction of apoptosis by imperatorin and heraclenin. 1510 79

Extracts of the plant St John's wort, Hyperforin perforatum L., have been used for centuries in traditional medicine, notably for the treatment of depression. One of their main lipophilic components, a natural prenylated phloroglucinol termed hyperforin (HF), has been identified as the major molecule responsible for the antidepressant effects of this plant. Within the last few years, a number of studies have demonstrated that HF displays, in addition, several other biological properties of potential pharmacological interest. They include an antibacterial capacity and inhibitory effects on inflammatory mediators. It is worth noting that HF also promotes apoptosis of various cancer cells from solid tumors and hematological malignancies, including B-cell chronic lymphocytic leukemia. In addition, HF inhibits the capacity of migration and invasion of different tumor cells, as well as exhibiting antiangiogenic effects. Altogether, these properties qualify HF as a lead structure for the development of new therapeutic molecules in the treatment of various diseases, including some malignant tumors.
Leukemia 2006 Sep
PMID:Hyperforin, a new lead compound against the progression of cancer and leukemia? 1679 Dec 62

We have isolated a new prenylated chalcone from the roots of Sophora flavescens (Leguminosae). We determined that structure of this compound is 7,9,2',4'-tetrahydroxy-8-isopentenyl-5-methoxychalcone (1) on the basis of spectroscopic analysis (1D and 2D NMR data). Compound 1 exhibited potent cytotoxicity against human acute promyelocytic (HL60), mouse lymphocytic (L1210) and human histiocytic (U937) leukemia cells.
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PMID:A new cytotoxic prenylated chalcone from Sophora flavescens. 1748 54


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