A study of the effect of papaverine in neuroblastoma using the experimental C1300 murine system

The effect of papaverine on transplantable C1300 murine neuroblastoma model was evaluated. Subcutaneous inoculation of A/J mice with 10(6) C1300 cells resulted in predictable tumor growth and animal death in 36 +/- 5 days. In 33% of control animals, lung and liver metastases were observed. Subcutaneous injections of papaverine prior to tumor inoculation and during the tumor growth failed to show any detectable effect on local growth of the tumor. Benign transformation of the primary tumor was not observed. However, papaverine injection 21 days after tumor inoculation was associated with only 9% incidence of metastatic development. Papaverine treatment, when started one day prior to tumor inoculation or 10 days after tumor implant, resulted in complete prevention of all detectable metastatic growth, while having no apparent effect on local tumor growth. Further study of papaverine effect in the neuroblastoma murine model is indicated.