Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0677930 (primary tumor)
 20,210 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In this preliminary report, evaluation of nontraditional agents has been used to evaluate control of metastasis. This androgen-sensitive rate prostatic adenocarcinoma has been subject to the treatments of heparin, indocin, and castration, as well as combinations of castration, heparin, indocin, and cyclophosphamide. Tumor volume, metastasis, and determination of regression of primary tumor have been evaluated. Heparin and indocin both reduced metastasis without affecting tumor volume in this study. The combination of castration and cyclophosphamide was most effective in reducing tumor volume when compared to the other groups.
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PMID:Nb rat prostate adenocarcinoma model androgen-sensitive tumor: metastasis control. 688 34

The effect of low-dose heparin on spontaneous metastasis formation was studied with the PA-III rat prostate adenocarcinoma cell line model system. In LW rats given heparin iv at a dose of 1,000 U/kg body weight (three times/wk), the metastatic spread of implanted PA-III cells from the footpad through ipsilateral lymphatics to the lungs was enhanced. The weights of the draining lymph nodes (popliteal, inguinal, and axillary) and the number of lung tumor colonies were significantly increased compared with those in the saline-treated control tumor-bearing rats. The growth of the primary tumor was also enhanced. Heparin alone did not induce enlarged lymph nodes in rats nor did it change the growth pattern of PA-III cells in vitro. The accelerated metastatic spread of the PA-III cells was possibly related to the destruction of the oncolytic activity of the very low-density lipoprotein by the lipoprotein lipases induced by the iv administration of heparin. However, the possibility that other mechanisms could be operative in this phenomenon has not been ruled out.
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PMID:Metastasis-enhancing effect of heparin and its relationship to a lipoprotein factor. 692 14

Classic studies indicate that the formation of tumor cell-platelet complexes in the blood stream is important in facilitating the metastatic process. Metastasis in animal models can be inhibited by heparin, and retrospective analyses of heparin use in human cancer have shown promise. However, most follow-up human studies using vitamin K antagonists have failed, and conclusive proof for other previously proposed mechanisms of heparin action is lacking. Carcinoma progression and metastasis are associated with overexpression of sialylated fucosylated mucins. Structurally similar molecules happen to be natural ligands for vascular adhesion molecules called the selectins. Heparin also happens to be a good inhibitor of P-selectin, which is expressed on activated platelets or endothelial cells. We have found that heparin blocks P-selectin-mediated interactions of endogenous platelets with sialylated fucosylated mucins on circulating carcinoma cells and that this reduces tumor cell survival. The use of more specific and selective P-selectin inhibitors will some day help to dissect the relative importance of this mechanism of heparin action in cancer. Meanwhile, we suggest that the failure of vitamin K antagonists to improve cancer prognosis should be ignored and that heparin therapy should be immediately revisited under this new paradigm. Unlike the suggestions in most previous studies, we propose that heparin use should be reexplored specifically during the interval from initial visualization of a primary tumor until just after its definitive surgical removal. A suggested clinical trial is outlined.
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PMID:Heparin inhibition of selectin-mediated interactions during the hematogenous phase of carcinoma metastasis: rationale for clinical studies in humans. 1188 26

Heparin treatment, at human equivalent doses, modulates coagulation parameters in mice similarly to the human situation. Heparins were tested in various melanoma metastasis models for their antimetastatic activity. Heparins were active against melanoma metastasis without influencing the primary tumor. Tumor cell-induced platelet aggregation was not the primary target of heparins, since melanoma cells were not active in this respect. Our results support the notion that heparins have antimetastatic activity.
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PMID:[Heparin inhibits metastatization of experimental melanoma]. 1552 Aug 74

Heparin and its derivatives are known to attenuate cancer metastasis in preclinical models, but have not been used clinically due to adverse bleeding effects. This study compared the efficacy of S-NACH (a sulfated non-anticoagulant heparin) versus tinzaparin (a low molecular weight heparin) in inhibiting metastasis of a growing primary tumor and following surgical excision of primary tumor in a pancreatic cancer mouse model. The efficacy of S-NACH versus tinzaparin on metastasis of the primary tumor was evaluated in each experiment using IVIS imaging. Athymic female mice were treated with S-NACH or tinzaparin, and 30 min later luciferase-transfected pancreatic cancer cells (Mpanc96) were implanted into the spleen; treatment was continued daily until termination. Next we studied the effect of S-NACH versus tinzaparin on metastasis after surgical excision of the primary tumor after 3 weeks of daily treatment with S-NACH or tinzaparin. S-NACH reduced surgically induced metastasis (p<0.01) and tumor recurrence (p<0.05) relative to control. Histopathological studies demonstrated significant increase in tumor necrosis mediated by S-NACH and to lesser extent by tinzaparin as compared to control group. Furthermore, either S-NACH or tinzaparin upregulated the expression of the junctional adhesion molecule E-cadherin in pancreatic cancer cells where its low expression enhances cancer cell migration and invasion. In terms of bleeding time (BT), S-NACH did not affect BT as compared to tinzaparin, which doubled BT. These data suggest that S-NACH is an effective and safe anti-metastatic agent and warrants further clinical evaluation.
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PMID:Anti-metastasis efficacy and safety of non-anticoagulant heparin derivative versus low molecular weight heparin in surgical pancreatic cancer models. 2553 18