CICAPROST DOES NOT AFFECT TUMOR INHIBITORY POTENTIAL OF CYTOSTATIC DRUGS

Cicaprost, a stable prostacyclin analogue with antimetastatic potentia l, was investigated as regards its effect on the tumor inhibitory pote ntial of cytostatic drugs exhibiting different modes of action in the MXT-OVEX mouse mammary carcinoma. Cicaprost itself in doses of 0. 5 mg /Kg and 1.0 mg/Kg po. daily had no effect on the growth of the sc. -im planted tumor cis-Platinum at a dose of 1.5 mg/Kg sc. strongly inhibit ed tumor growth, while at a dose of 0. 75 mg/Kg only a weak effect was seen. The efficacy of both treatments was not altered by cicaprost (0 .5 mg/Kg; po.) administered in two different schedules. Whereas cyclop hosphamide (400 mg/Kg; sc.) completely inhibited the growth of the MXT -OVEX tumor, doxorubicin (2.5 mg/Kg; sc.) and 5-FU (10 mg/Kg; sc.) had only a weak effect. The combination of cicaprost with either cyclopho sphamide, doxorubicin or 5-FU did not alter the inhibition of tumor gr owth. On the basis of these data, we anticipate that the antimetastati c agent cicaprost can be used in combination with cytostatic regimens without interfering with their clinical effectiveness.