Keyhole limpet hemocyanin: an effective adjunct against melanoma in vivo

BackgroundWe have previously demonstrated the potent in vitro antiproliferative effects of keyhole limpet hemocyanin (KLH) against melanoma. Our prior studies directed us to hypothesize that KLH would be effective in vivo against melanoma, alone and in combination with conventional immunotherapy.MethodsMice were inoculated with 2 × 107 HTB68 cells and randomized to 6 groups. Treatment groups consisted of control, KLH 200 μg, alpha interferon (AIFN) 1000 IU, interleukin-2 (IL-2) 5000 IU, KLH + AIFN, and KLH + IL-2.ResultsKLH + IL-2 exhibited the greatest reduction in tumor volume (30%) as compared to control (P = .014), followed by KLH + AIFN (28%, P = .031). Singly treated animals had less tumor inhibition: IL-2 (30%, P = .022), KLH (18%, not significant), and AIFN (16%, not significant).ConclusionsKLH augments the effects of AIFN, one of the standard immunotherapeutic agents against melanoma in vivo. Further in vivo and early clinical studies into the effects of KLH as both a single and combined agent are warranted.