Reductive Effect of Aspirin Treatment on Primary Tumor Growth and Metastasis of Implanted Fibrosarcoma in Rats2

Abstract

For suppression of primary tumor growth and metastatic spread, aspirin and theophylline, either alone or combined, were given daily to inbred female BN rats after sc implantation of a syngeneic nonimmunogenic tumor. Treatment with 200 mg aspirin/kg (body wt) resulted in a statistically significant regression of tumor growth as well as of the number of metastases in the lungs. Aspirin given in a lower dose (20 mg/kg) did not show significant difference from the vehicle group. Theophylline (75 mg/kg) significantly increased primary tumor growth as well as lung metastases. Inhibition of in vitro platelet aggregation, determined in whole blood taken from non-tumor-bearing animals treated with the same therapeutic regimen, was most pronounced in those groups in which tumor growth and spread were significantly retarded. However, this positive correlation between inhibition of tumor spread and platelet aggregation was not associated with a favorable balance of prostacyclin and thromboxane A2 in these animals.

A Review of Thrombosis and Antithrombotic Therapy in Microvascular Surgery

“…The time of aspirin administration is important. Kort et al [40] observed that when administered 30 min prior to surgery aspirin had no antithrombotic effect, while other authors describe a significant increase in vessel patency when administered 10 h preoperatively [41]. Low-dose (5 mg/kg) aspirin has been shown to be sufficient to irreversibly block platelet thromboxane production while at the same time preserving endothelial prostaglandin I 2 and other antithrombotic prostaglandin synthesis [42].…”

Treatment with a non-steroidal anti-inflammatory agent delays the growth of spontaneous pulmonary metastases of a mammary adenocarcinoma of non-detected immunogenicity

“…Only a few studies, however, addressed the role of these agents in the control of metastases (Kort et al, 1986;Fisher et al, 1989;Fulton et al, 1991). In this report, we showed that oral treatment of mice with piroxicam delays the growth of spontaneous pulmonary metastases of a mammary adenocarcinoma of nondetected immunogenicity, upon surgical removal of the primary tumour.…”

Quercetin enhances tumorigenicity induced by N-ethyl-N′-nitro-N-nitrosoguanidine in the duodenum of mice

“…Another inhibitor of cyclo-oxygenase, aspirin, also shows pleiotropic effects on tumorigenesis. Aspirin increases the incidence of rat gastric tumors induced by MNNG 31) , although aspirin reduces the growth of colon tumors and fibrosarcomas in rodents 32,33) . Moreover, aspirin is not a carcinogen alone 31) , similar to quercetin.…”