Nanoparticles as a Hedgehog signaling inhibitor for the suppression of cancer growth and metastasis.

Nanoparticles (NPs) have been intensively explored for the treatment of tumors during the past decade, yet little information has been provided on the NPs' inherent therapeutic activity against cancers. With this goal in mind, we reveal that biocompatible silicon (Si) NPs (SiNPs) feature excellent anti-growth and anti-metastasis activities against prostate cancer cells that show aberrant activation of the Hedgehog (HH) signaling pathway. Without activation by the Sonic hedgehog (Shh)-agonist, mouse embryonic fibroblast (NIH3T3) cells show no response to SiNP exposure. The distinct inhibitory effect of SiNPs on the HH signaling pathway leads to significant suppression of the proliferation, migration, and invasion of human prostate cancer cells. Crucially, in two mouse tumor models, the growth and metastasis of prostate cancer cells are also efficiently inhibited by SiNPs.