Using a phage–display technique we discovered a 9-amino acid cyclic
peptide named ALOS4 exerting strong anti-cancer properties in vivo and in vitro. Namely, animals with subcutaneous melanoma treated with ALOS4 demonstrated an inhibition of tumor growth and disease progression without any toxicity. While further studying the role of ALOS4 in interferon regulation in malignancy, we found that ALOS4 treatment leads to a decrease of pro-inflammatory cytokines. ALOS4 anti-inflammatory properties are also supported by downregulation of most pro-inflammatory interleukins in the serum of mice subjected to chronic stress and treated with ALOS4. Furthermore, ALOS4 downregulated macrophage
quantity in the adipose tissue of these mice and inhibited murine macrophage
differentiation to proinflammatory M1 in vitro. Using a cell culture system in which synthetic double stranded RNA (dsRNA) and/or LPS simulates the effects of acute infection, we demonstrated that treatment with ALOS4 leads to a dramatic reduction in expression of interferon-response genes and nitric oxide (NO) production, further supporting its anti-inflammatory properties.