Related Experiment Videos
Role of vasoactive amines in the antitumor activity of endotoxin
Abstract:
To estimate a possible role of vasoamines in the antitumor action of endotoxin, effects of isoproterenol, serotonin and adrenaline on subcutaneously transplanted murine Meth A sarcoma and the capacity of these agents to elicit antitumor factors were studied. Macroscopically all agents induced tumor necrosis and a temporal tumor growth stop, but only endotoxin was capable of induction of complete tumor regression. Histology showed that all agents induced hyperemia by 4 h and hemorrhagic necrosis by 24 h. The latter was located superficially at the outside of tumors. Only serotonin and especially endotoxin induced substantial non-hemorrhagic necrosis in the remaining part of the tumors. Endotoxin induced a profound inhibition of the mitotic activity within the tumor, the effect of other agents was considerably less. Only endotoxin induced high levels of tumor necrosis factor, heat stable cytostatic factors and interferon in the circulation of mice treated with Corynebacterium parvum 14 days earlier. It is concluded that these and other data provide indirect but circumstantial evidence for a role of vasoamines in the induction of hyperemia and hemorrhagic necrosis by endotoxin. The latter two effects are probably causally related. It is suggested that non-toxic vasoamines may be useful adjuvants to other treatments of cancer.
Insights
Vasoamines like serotonin contribute to endotoxin
Area of Science:
- Immunology
- Pharmacology
- Oncology
Background:
- Vasoamines are endogenous compounds that can influence physiological processes.
- Endotoxins are known to possess antitumor properties.
- The specific role of vasoamines in endotoxin-mediated antitumor effects requires elucidation.
Purpose of the Study:
- To investigate the role of vasoamines in the antitumor activity of endotoxin.
- To assess the effects of isoproterenol, serotonin, and adrenaline on Meth A sarcoma.
- To determine the capacity of these agents to induce antitumor factors.
Main Methods:
- Subcutaneous transplantation of murine Meth A sarcoma.
- Administration of isoproterenol, serotonin, adrenaline, and endotoxin.
- Macroscopic and histological tumor analysis.
- Measurement of circulating antitumor factors (tumor necrosis factor, cytostatic factors, interferon).
Main Results:
- All tested agents induced tumor necrosis and temporary growth arrest.
- Endotoxin was the only agent to induce complete tumor regression.
- Histology revealed hyperemia and superficial hemorrhagic necrosis induced by all agents.
- Serotonin and endotoxin caused significant non-hemorrhagic necrosis.
- Endotoxin profoundly inhibited tumor cell mitotic activity.
- Endotoxin elevated antitumor factors in mice pre-treated with Corynebacterium parvum.
Conclusions:
- Vasoamines likely play a role in endotoxin-induced hyperemia and hemorrhagic necrosis.
- These vascular effects are possibly causally linked to antitumor activity.
- Non-toxic vasoamines may serve as potential adjuvants in cancer therapy.