Methotrexate induced apoptotic and necrotic chromatin changes in rat myeloid leukemia cells.

Objective: It was tested as to why low-dose methotrexate (MTX) effective against rheumatoid arthritis poses considerable health risk at higher doses.

Methods: The tumorigenic potential of My1/De blast cells was followed by cytology and by the kinetics of (18)FDG uptake. The toxicity of MTX on chromatin condensation was compared to predictive normal intermediates of chromosome condensation in control cells.

Metastatic hepatocarcinoma he/de tumor model in rat.

Unlabelled: The aim of this study is to select among potential tumor models that could be suitable to follow the metastatic spead of tumor cells. (18)FDG-PET tumor diagnostic test has been adapted to investigate tumor growth in vivo in local and metastatic rat models. Materials and Methods.

Fluvastatin-induced alterations of skeletal muscle function in hypercholesterolaemic rats.

Although statins, the most widely used drugs in the treatment of hyperlipidaemia, are generally accepted as efficient and safe drugs their side-effects on skeletal muscle have been reported with increasing frequency. The lack of an animal model in which these side effects would consistently be observed is one of the important drawbacks in studying statin associated myopathy. To overcome this and enable the studying of the effects of fluvastatin on skeletal muscles an animal model with high blood cholesterol levels was developed.

Incomplete chromatin condensation in enlarged rat myelocytic leukemia cells.

The distinguishable morphologic features of nuclei of acute myelogenous leukemia cells with enlarged size and finely distributed nuclear chromatin indicate incomplete chromosome condensation that can be related to elevated gene expression. To confirm this, interphase chromosome structures were studied in exponentially growing rat myelomonocytic leukemia 1 cells isolated at the University of Debrecen (My1/De cells). This cell line was established from primary rat leukemia chemically induced by 7,12-dimethylbenz[a]anthracene treatment.

Comparison of the tumorigenic potential of liver and kidney tumors induced by N-nitrosodimethylamine.

The aim of the study was to determine the tumorigenic potential of two cell lines established from N-nitrosodimethylamine induced rat hepatocarcinoma (HeDe) and mesenchymal renal tumors (NeDe). The basis of the distinction is that human cancers are known to overexpress facilitative GLUT transporters and TGF-beta1 protein. These proteins are linked to the increased metabolic energy consumption indicating uncontrolled growth and proliferation.

Lymphatic spread of mesenchymal renal tumor to metastatic parathymic lymph nodes in rat.

Rat mesenchymal renal tumor cells (NeDe) transplanted under the kidney capsule of F344 rats resulted in metastases in the parathymic lymph nodes. Tumor cells were isolated from these tumor-bearing lymph nodes and 106 cells were implanted under the kidney capsule. Tumor growth after this implantation could be traced within six days.

Renal capsule-parathymic lymph node complex: a new in vivo metastatic model in rats.

Background: The ultimate cause of cancer death is, in most cases, the appearance of metastases. The aim of the present study was to contribute to animal experimental investigations of metastatic tumor development.

Materials And Methods: Rat hepatocarcinoma (He/De), mesoblastic nephroma (Ne/De) cells, and in other cases tumor-bearing lymph nodes were transplanted under the renal capsule of F344 rats.

Fungal siderophores function as protective agents of LDL oxidation and are promising anti-atherosclerotic metabolites in functional food.

Iron-mediated oxidation of low-density lipoprotein has been implicated in the pathogenesis of vascular disorders such as atherosclerosis. The present investigations were performed to test whether hydrophobic fungal siderophores - hexadentate trihydroxamates desferricoprogen, desferrichrome, desferrirubin, and desferrichrysin - might suppress heme-catalyzed LDL oxidation and the toxic effects of heme-treated LDL on vascular endothelium. Indeed, two of these - desferricoprogen and desferrichrome - markedly increased the resistance of LDL to heme-catalyzed oxidation.

Chemically induced carcinogenesis affecting chromatin structure in rat hepatocarcinoma cells.

A new, chemically induced animal tumor cell line (HeDe) was established and characterized by its property of causing aggressively growing tumors in specific strain of rats and changes in the chromatin structure. Results show that (1) the nuclear material in nuclei of normal resting (G0) hepatocytes consists mainly of decondensed veil-like chromatin, chromosomes being clustered in six lobular domains; (2) nuclei of HeDe cells contain primarily supercoiled chromatin; or (3) the nuclear material of tumor cells undergoes apoptosis seen as apoptotic bodies. Heterogeneity of chromatin structures was expressed as contour/area ratio and was nine times higher in apoptotic cells and two times higher in tumor cells compared to resting cells.

Different anticancer effects of fluvastatin on primary hepatocellular tumors and metastases in rats.

Rats (FLF1) were pretreated with 2 and 20 mg/kg/day fluvastatin (Flu), and after 6 weeks, hepatocellular tumor cells were inoculated under the left renal capsule. At different times, growth and pyruvate kinase (PK) activity of the primary tumors and lymph node metastases were determined. Flu had a dose-dependent inhibitory effect on primary and metastatic tumors, and the inhibitory effect on growth and PK activity in metastases were higher than in primary tumors.

HMG CoA reductase inhibitor fluvastatin arrests the development of implanted hepatocarcinoma in rats.

Background: Fluvastain (Flu) is widely accepted to have anticancer effect although its in vivo chemopreventive ability in cancer has not been studied. The therapeutic and chemopreventive effects of Flu were compared in vivo in the present study.

Materials And Methods: Under the left renal capsule of FLF1 hybrid rats 10(6) hepatocarcinoma cells were implanted (He/De14) on sponge disc.