Prostate cancer (PCa) is the second most frequently diagnosed
cancer in men worldwide. Dialyzed Leukocyte Extracts (DLEs) are heterogeneous mixtures of low-molecular-weight
peptides that improve clinical responses in various diseases. Here, we analyzed the effects of TransferonTM, a commercial DLE with characterized active pharmaceutical ingredient and proven batch-to-batch reproducibility, in preclinical models of PCa. We employed v-Src-transformed murine prostate epithelial (PEC-Src) cells, which recapitulate the transcriptional profiles in human PCa, can be grown in immunocompetent mice, and consistently form bone and
brain metastases. In vitro, TransferonTM did not induce cytotoxicity nor alterations in migration /invasion of PEC-Src cells. In vivo, TransferonTM reduced metastatic dissemination after intracardiac injection of PEC-Src and inhibited
tumor growth of subcutaneous isotransplants. The
antineoplastic effect of TransferonTM correlated with changes in
tumor infiltration, increased serum concentrations of
IL-12 and CXCL1, and reduced levels of
VEGF. Our results suggest that the
antineoplastic effect produced by TransferonTM is due to its immunomodulatory activity and not by a direct effect on
cancer cells, and indicate that TransferonTM could be beneficial as adjuvant
therapy in PCa patients.