Because Flt3L expression by cancer cells themselves might differentially regulate immune cell infiltration as soon as tumors become different in size, we performed gene therapy based on the hydrodynamic administration of a secreted Flt3L-encoding plasmid (FL), which results in liver production of the growth factor,7 to separately test its effect in parental B16F10 growth. This evidence concerns the gene FLT3LG and cancer.