The aim of this study was to investigate the anti-tumor effects of molluscan hemocyanins (Hcs) isolated from the marine snail Rapana venosa (RvH) and the garden snail Helix lucorum (HlH) on human bladder cancer cell lines. The antitumor effect of the native molecules of the above-mentioned Hcs and their subunits were examined in comparison to keyhole limpet hemocyanin (KLH), which is the most thoroughly studied Hc. The experiments were conducted using 2 human bladder cancer cell lines: CAL-29 and T-24. Doxorubicin hydrochloride (DOX) and mitomycin-C (MIT-C), which are routinely used in clinical practice to treat bladder cancer, were used for comparison. The viability of the 2 bladder cancer cell lines, used at a concentration of 20,000 cells/well, was measured by WST-1 assay at 24, 48 and 72 h after treatment with the above-mentioned Hcs and their isoforms at a concentration ranging from 0.8 to 500 μg/ml. A direct growth inhibitory effect on the tumor cells was observed mainly after treatment with the native molecule of HlH and the structural subunit, RvH1, at a concentration of 500 μg/ml. The native molecule of RvH exhibited an efficacy similar to that of KLH. However, the observed growth inhibitory effect of HlH was superior to that observed for KLH and RvH, when used at the same concentration. These findings demonstrate the antitumor effect of other Hcs, apart from KLH. Our data suggest that the native molecule of HlH and the subunit, RvH1, are alternative candidates for the treatment of human superficial bladder cancer.
Keywords: bladder cancer; cell line; hemocyanin; therapy.