Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Studies investigating the role of thromboxane A2 and prostacyclin in cancer of the female breast and genital tract are reviewed. Whereas thromboxane A2 was found to promote the tumour growth and metastasis, prostacyclin exerted a protective effect in maintaining vascular and platelet homeostasis. Thus, monitoring of prostacyclin and thromboxane levels in plasma and urine of cancer patients may be essential for the evaluation of tumour growth and metastasis. Of all modulators of thromboxane and prostacyclin biosynthesis, nafazatrom was found to exhibit promising results for the treatment of advanced breast cancer, although its use in the routine therapy is questionable at this stage.
Cancer Metastasis Rev 1992 Nov
PMID:Clinical significance of prostacyclin and thromboxane in cancer of the female breast and genital tract. 142 25

Prostaglandins and other eicosanoids have been studied extensively in their physical, biochemical, biophysical and pharmacological aspects. However, studies on their role in tumor progression, especially metastases are relatively recent. Following a brief overview of the history of discovery and metabolism of eicosanoids and other fatty acids, we discuss the functions of these fatty acids (with emphasis on prostacyclin, thromboxane A2, 12-hydroxyeicosatetraenoic acid and 13-hydroxyoctadecadienoic acid) in cell transformation, tumor promotion and particularly in tumor cell metastasis. The relation between these monohydroxy fatty acids and tumor cell metastasis is discussed from three different perspectives, i.e., their effects on tumor cells, on platelets and on endothelial cells. The mechanism of these effects are then addressed at cell adhesion molecule, motility, protease, cell cytoskeleton, protein kinase and eicosanoid receptor levels. Finally, regulation of three key enzymes which generate eicosanoids (phospholipase, prostaglandin endoperoxide synthase and lipoxygenase) is explored.
Cancer Metastasis Rev 1992 Nov
PMID:Fatty acid modulation of tumor cell-platelet-vessel wall interaction. 142 24

Investigations on mechanisms of metastatic tumour spread revealed a role for compounds that inhibit tumour dissemination at the time of hematogenous dissemination. The platelet aggregation inhibitor prostacyclin and its stable analogues were shown to inhibit tumour-cell-induced platelet interaction as well as tumour cell adhesive mechanisms. This study concentrates on the effect of the stable prostacyclin analogue cicaprost: 5-[(E)-(1S,5S,6S,7R)-7-hydroxy-6-[(3S,4S)-3-hydroxy-4-methylnona-1 ,6- diinyl]-bicyclo[3,3,0]octan-3-ylidene]-3-oxapentanoic acid (Schering AG), as cyclodextrin clathrate, on spontaneous tumour metastases of two different carcinomas of the rat. In Cop rats bearing spontaneously metastasizing R 3327 MAT Lu prostate carcinomas, cicaprost (1.0 mg/kg p.o. daily) inhibited the number of lung metastases by about 80%, whereas the lower doses (0.1 and 0.5 mg/kg) exhibited borderline efficacy. In female Wistar-Furth rats bearing s.c. implanted SMT 2A mammary carcinomas, spontaneously metastasizing into regional lymph nodes and lungs, cicaprost (0.1, 0.5 and 1 mg/kg) p.o. daily exhibited a dose-dependent inhibition of the number of lung metastases. Five out of ten animals treated by 1 mg/kg were free of visible lung metastases. The weight of the axillary lymph node was significantly reduced by the 1 mg/kg dose of cicaprost, whereas lower doses had no effect on the weight of the lymph nodes. The growth of the primary tumour was not influenced by cicaprost in the R 3327 MAT Lu prostate carcinoma nor in the SMT 2A mammary carcinoma in the dose range tested. In conclusion, the stable prostacyclin analogue cicaprost exhibits a strong antimetastatic action in two metastasizing tumours of the rat and interferes with the steps not only of haematogenous, but also of lymphogenous metastasis.
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PMID:The prostacyclin analogue cicaprost inhibits metastasis of tumours of R 3327 MAT Lu prostate carcinoma and SMT 2A mammary carcinoma. 162 41

Much attention has recently focused on the role of tumor cell-platelet interaction in the metastatic cascade. Prostacyclin and stable prostacyclin analogues have been shown to inhibit specifically the formation of metastases in experimental tumor models. This action is based on their ability to reduce the attachment of tumor cells to platelets and to inhibit adhesion of tumor cells-platelet aggregates to the endothelial lining. To investigate the antimetastatic potential of two prostacyclin analogues (Iloprost and Eptaloprost, Schering AG), we have tested these compounds in the spontaneously metastasizing R 3327 MAT Lu prostate carcinoma of the Cop rat in two types of experiments. Treatment was performed for 33 days, starting one day before s.c. implantation of the tumor. The primary s.c.-implanted tumor remained in situ throughout the experiment. In the first test, Iloprost (0.3 micrograms/kg/min) and Eptaloprost (0.1 micrograms/kg/min) were administered via Alzet mini pumps s.c.. There was a considerable reduction of the number of visible lung metastases by Eptaloprost. In the second test, Eptaloprost was administered p.o. in doses of 0.1 and 0.5 mg/kg daily. The number of lung metastases was significantly reduced. Both compounds had no effect on the growth of the primary tumor in the first as well as in the second test. These data show that the prostacyclin analogue Eptaloprost has a significant antimetastatic activity in a spontaneously metastasizing tumor model and thus merits further investigation.
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PMID:Effects of prostacyclin analogues in in vivo tumor models. 170 84

Since an involvement of platelet aggregation in the metastatic process has been found, platelet activation inhibitors were investigated for their potential to reduce tumor metastases. Recent in-vitro and in-vivo investigations showed an antimetastatic effect of prostacyclin (PGI2) and stable prostacyclin analogues. This study concentrates on the effect of the stable prostacyclin analogue Cicaprost (Schering AG) on tumor metastases in two metastasizing tumors of rodents. C57BL/6 mice bearing s.c.-implanted M5076 reticulum sarcoma were treated with Cicaprost in doses of 0.1-1.0 mg/kg throughout the experiment. Cicaprost in all doses tested reduced the number of liver metastases in a statistically significant manner. The 1.0 mg/kg dose, which decreases the median number of liver metastases to more than 93% compared to the control, was most effective. Cicaprost in the 0.5 mg/kg dose reduced the number of liver metastases in mice bearing i.v.-implanted M5076 reticulum sarcoma. In Cop-Fisher rats bearing s.c.-implanted spontaneously metastasizing R3327 MAT Lu prostate carcinoma, Cicaprost in a dose of 1.0 mg/kg p.o. daily strongly reduced the number of lung metastases. These results indicate that Cicaprost is a potent inhibitor of tumor metastases in different tumor models in rodents.
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PMID:Cicaprost inhibits metastases of animal tumors. 176 1

Adhesion of tumor cells to vascular endothelial surfaces is one of the key steps in metastatic dissemination. Several factors are believed to be implicated in the regulation of the adhesive properties of tumor cells. We show that the adhesion of five different tumor cell lines, all of them of human origin, to human umbilical vascular endothelial cells (ECs) significantly increases following pretreatment of ECs with the cytokines interleukin-1 and tumor necrosis factor, whereas tumor cell/EC interactions remained unchanged after incubation with interferon-gamma. Significant augmentation in tumor cell adhesion was also observed when ECs were treated with the lipoxygenase inhibitors salicylate and the compound BW755C. In all cases, increased tumor cell adhesion was concomitant with significant decreases in the EC levels of linoleic acid, lipoxygenase-derived metabolite 13-hydroxy-octadecadienoic acid (13-HODE). On the contrary, pretreatment of the EC monolayers with aspirin did not result in any changes towards tumor cell adhesion. These results suggest that tumor cell/EC interaction is modulated, at least in part, by intracellular levels of 13-HODE and is independent of prostacyclin (PGI2) production by the ECs.
Invasion Metastasis 1991
PMID:Effects of endothelial cell treatment on 13-HODE and prostacyclin synthesis and its correlation with tumor cell-vascular endothelial cell adhesion. 180 Apr 51

Gestational choriocarcinoma metastasizes rapidly, in which process the vasoactive prostanoids may be significant. We therefore compared the urinary excretion of prostacyclin and thromboxane A2 (TxA2) metabolites in 19 women with gestational choriocarcinoma and 20 healthy age-matched women by assessing spot urine samples for 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) and 2,3-dinor-6-keto-prostaglandin F1 alpha (2,3-dinor-6-keto-PGF1 alpha) (degradation products of prostacyclin) as well as for thromboxane B2 (TxB2) and 2,3-dinor-TxB2 (degradation products of TxA2) by high-pressure liquid chromatography, followed by radioimmunoassay; the data were related to urinary creatinine concentration. The urinary output of 6-keto-PGF1 alpha [29.56 +/- 7.0 versus 25.08 +/- 3.91 ng/mmol creatinine (SE)] in patients with choriocarcinoma was normal, but that of 2,3-dinor-6-keto-PGF1 alpha in cancer patients was higher than in controls (24.44 +/- 5.20 versus 14.84 +/- 1.94, P less than 0.02), as was that of TxB2 (22.72 +/- 4.69 versus 9.69 +/- 1.52, P less than 0.001) and 2,3-dinor-TxB2 (114.21 +/- 30.81 versus 51.81 +/- 10.40, P less than 0.01). The ratio of net prostacyclin output (6-keto-PGF1 alpha plus 2,3-dinor-6-keto-PGF1 alpha) to the net TxA2 output (TxB2 plus 2,3-dinor-TxB2) in cancer patients [0.52 +/- 0.1 (SE)] was lower (P less than 0.03) than in the controls (0.83 +/- 0.1), and in an inverse relation (r = -0.54, P less than 0.05) to the scoring index of poor prognosis for the disease. We conclude that the prostanoid excess in gestational trophoblastic disease, as evidenced for the first time in this study, may originate from choriocarcinoma cells, or may be a paraneoplastic phenomenon, and we conclude also that TxA2 excess may contribute to the tumor growth and/or formation of metastases.
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PMID:Urinary excretion of degradation products of prostacyclin and thromboxane is increased in patients with gestational choriocarcinoma. 186 36

Prostaglandins (PGs) have been shown to inhibit tumour metastases in experimental animal systems. Nafazatrom is a pyrazolinone derivative that increases endogenous prostacyclin (PGI2) and has experimental anti-cancer activity. In the present study, nafazatrom was given to 47 women with advanced breast cancer; objective remission of metastases was seen in 2 patients and stabilisation of disease in 1 case. Nafazatrom was safe and well tolerated.
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PMID:A clinical study of nafazatrom in advanced human breast cancer. 199 90

Human pancreatic cancer is an aggressive malignancy, with systemic metastases ultimately accounting for its grave prognosis. Arachidonic acid metabolites known to affect platelet function also interfere with tumor growth and metastases. We evaluated the effect of prostacyclin on the hepatic metastases of a human pancreatic cancer in a nude mouse model. The mean surface area of tumor on the liver was significantly reduced in all treatment groups. In the control group 485 mm2 of tumor was present on the liver surface. Animals treated with 200 micrograms of prostacyclin 0.5 hr prior to the injection of tumor cells had 21 mm2 of tumor present on the liver surface (P = 0.004). Similarly, 400 micrograms of prostacyclin caused a reduction of tumor surface area to 20 mm2 (P = 0.004). The maximal reduction of tumor surface area, 11 mm2, was observed when 200 micrograms of prostacyclin was given 0.5 hr prior to and 4.0 hr after the injection of tumor cells (P = 0.003). For the group given 200 micrograms of prostacyclin 4.0 hr after the injection of tumor, the surface area of tumor was 85 mm2 (P = 0.017). The number of tumor colonies on the liver surface was significantly reduced from 20 to 11 when 200 micrograms of prostacyclin was administered intraperitoneally 0.5 hr before and 4.0 hr after the injection of tumor cells (P = 0.047). These results indicate that prostacyclin has antimetastatic activity on hepatic metastases from a human pancreatic adenocarcinoma in the nude mouse.
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PMID:Effects of prostacyclin on hepatic metastases from human pancreatic cancer in the nude mouse. 211 65

Metastasis is a multistep phenomenon in which platelets appear to play an important role. This study examined several compounds for their effects on experimental hepatic metastasis and on human pancreatic tumor cell-platelet interactions. Prostacyclin (PGI2) and forskolin (stimulators of platelet adenylate cyclase) and ketoconazole (inhibitor of lipoxygenese and thromboxane synthetase) were used in order to investigate their effects on hepatic metastases from a human pancreatic tumor cell (RWP-2) in the nude mouse. The tumor cells were injected intrasplenically and the animals were divided into control, prostacyclin (PGI2 200 micrograms), forskolin (150 micrograms), and ketoconazole (180 micrograms) groups. All three drugs were administered intraperitoneally 30 minutes before and 24 hours after the tumor cell injections. Statistically significant differences were observed between control and treated groups in tumor surface area (P less than 0.001), percentage of liver surface area occupied by tumor (P less than 0.001), and number of tumor colonies (P less than 0.004 for prostacyclin, P less than 0.005 for forskolin, and P less than 0.001 for ketoconazole). These agents also strongly inhibited RWP-2-induced platelet aggregation in human platelet-rich plasma.
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PMID:Inhibition of hepatic metastasis from a human pancreatic adenocarcinoma (RWP-2) in the nude mouse by prostacyclin, forskolin, and ketoconazole. 240 57


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