Targeted dendrimer chemotherapy in an animal model for head and neck squamous cell carcinoma.

PURPOSE: Nanoparticle drug delivery offers a potential solution in the treatment of cancer. Using a heterotopic tumor model for head and neck squamous cell carcinoma (HNSCC), tumors of variable folate binding protein-alpha (FBP-α) have been treated to delineate receptor necessity as well as efficacy and toxicity of folate targeted chemotherapy.
MATERIALS AND METHODS: University of Michigan Squamous Cell Carcinoma (UM-SCC) and American Type Culture Collection (ATCC) cell lines were screened using quantitative real-time polymerase chain reaction for FBP-α expression. Acetylated generation 5 dendrimers conjugated to the targeting moiety folic acid and the therapeutic moiety methotrexate were fabricated and administered to severe combined immunodeficiency (SCID) CB-17 mice inoculated with UM-SCC-1, UM-SCC-17B, and UM-SCC-22B cancer cells. Mice were injected with targeted therapy, free methotrexate, or saline control and monitored for drug efficacy and toxicity.
RESULTS: Targeted therapy was effective relative to receptor level expression. Targeted therapy could be delivered in molar doses 3 times that of free drug. The treatment of a high folate expression tumor cell population was noted to have increased efficacy over saline (P < .01) and free methotrexate (P = .03) as well as decreased systemic toxicity.
CONCLUSIONS: This report represents the first translation of dendrimer-based chemotherapy to HNSCC and underscores its effectiveness as an antitumor agent in human cancer cell lines with lower levels of FBP-α than the in vitro and in vivo models previously reported.