Targeting Prostate Cancer with a Combination of WNT Inhibitors and a Bi-functional Peptide

AIM: Advanced renal cancer has still a very poor prognosis. We combined wingless-related integration site (WNT) inhibitors with a bi-functional peptide, as previous research has proven their individual efficacy in cancer therapy. Each targets cancer cells differently. We wanted to determine whether they have an additive effect. MATERIALS AND METHODS: Our bi-functional peptide consists of a target domain (LTVSPWY) and a lytic domain (KLAKLAK)2. We used three WNT inhibitors: Ethacrinic acid, ciclopirox olamine, piroctone olamine and combined each with the bi-functional peptide. They were tested on three different renal cancer cell lines using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium-bromide (MTT) assay. RESULTS: We demonstrated a synergistic effect of WNT inhibitors with the bi-functional peptide. The vitality of cancer cells was reduced significantly (p<0.05), while healthy cells were mostly unaffected. CONCLUSION: The combination of WNT inhibitor and the bi-functional peptide may lead to new treatment options as toxic side-effects can be reduced due to the lower doses of agent required.