Regulation of heparin-binding EGF-like growth factor expression by phorbol ester in a human hepatoma-derived cell line

Rationale for clinical trials of coagulation: reactive drugs in hepatocellular carcinoma

Evidence for the regulation of cancer growth by components of the blood coagulation mechanism provides abundant opportunity for the development of novel hypotheses for the experimental treatment of malignancy. Information available on the heterogeneity in mechanisms of interaction between various cancer cell types, and procoagulant and fibrinolytic pathways, platelets, glycosaminoglycan-regulated growth factors and cell-adhesion molecules indicates that insightful clinical trial design may allow targeting of individual cancer cell types with agents capable of intercepting mechanisms of growth control that are relevant to specific tumor types. This paper reviews the evidence that the common anticoagulant, heparin, inhibits hepatocellular carcinoma cell proliferation and hepatocellular carcinoma tumor dissemination in experimental animals. Clinical trials of heparin performed to date have shown increased tumor response rates and survival in other tumor types. Expression of urokinase-type plasminogen activator by hepatocellular carcinoma cells enhances tumor cell proliferation, motility, invasiveness and metastatic dissemination. Inhibition of the urokinase-type plasminogen activator/plasmin system by protease inhibitors such as aprotinin (Trasylol, Bayer) have shown improvement in the clinical course of certain tumor types. These data suggest that drugs that are well-known in the field of vascular medicine may find a role in the treatment of hepatocellular carcinoma, a common tumor type that has resisted containment by other means.

Immobilization stress induces c-Fos accumulation in liver

Acute stress-induced injury in tissues has been revealed by both biochemical markers in plasma and microscopy. However, little is known of the mechanisms by which tissue integrity is restored. Recently, induction of early response genes such as c-fos has been reported in the heart and stomach of immobilized animals. Herein, we show that immobilization stress in mice increased plasma alanine aminotransferase activity, a marker of liver damage. c-Fos protein accumulation in liver was induced by stress after 20 minutes of immobilization and persisted for 3 hours. Immobilization also induced the release of epidermal growth factor (EGF) from submandibular salivary glands and a transient increase in EGF concentration in plasma. Although EGF administration induced a 2.5-fold increase in c-Fos mass in the liver of anesthetized mice, sialoadenectomy (which abolished the effect of immobilization on plasma EGF) did not affect the stress-induced rise in plasma alanine aminotransferase activity or liver c-Fos accumulation. Therefore, we conclude that immobilization stress induces c-Fos accumulation in liver and that this effect is not triggered by the increase in plasma EGF concentration.