gms | German Medical Science

Although therapy for head and neck cancer has made remarkable progress in the last years, still there is an urgent need for drugs with a new active principle, which selectively kills cancer cells. Many animal cationic antimicrobial peptides (AMP) with a strong affinity to negative charged cell membranes have a higher sensitivity to cancer cells and therefore an antitumoral activity. But to date only few is known on antitumoral activity of human AMP. Therefore the aim of this study was to investigate the in vitro antitumoral activity of human LL-37. Cytotoxicity was measured in a commercially available assay as a function of LDH concentration within the supernatants of adherent cells using an ELISA. LL-37 activity was investigated in a dose- and time-dependent manner on squamous hypopharyngeal cancer cell line HTB-43 and a benign epithelial control cell line HaCat. The LD50 in HTB-43 was 13µg/ml LL-37. LL-37 didn’t show any cytotoxicity in the benign controls at that concentration. Only at the highest used concentration of 50 µg/ml LL-37 a cytotoxic activity of 39 % was evident in the benign control compared to 100 % in the squamous cancer cells. The LD50 in HTB-43 was already reached after 3 hours. Thus, LL-37 seems to have a predominant selective antiumoral activity. The therapeutic capability of LL-37 for the development of new drugs for adjuvant therapy of head and neck cancer remains to be seen.

This investigation was supported by a Research Grant of the Christian-Albrechts-University.