Growth inhibition of human malignant melanoma transfected with the human interferon-beta gene by means of cationic liposomes

Among the various types of human interferons, human interferon-beta (HuIFN beta) has the strongest anti-proliferative activity against human melanoma cell lines. Therefore, we investigated the growth inhibitory effect of a ca tionic liposome containing the HuIFN beta gene on human melanoma cell lines in vitro and in vivo. After transfection with liposomes containing the HuI FN-beta gene, human melanoma cell lines produced HuIFN beta in the culture medium at levels ranging from 67 to 3.8 IU/ml on day 6, and growth of the c ells was inhibited by 71-92%. Moreover, six injections of liposomes contain ing the HulFN beta gene completely eradicated human melanoma nodules transp lanted onto the backs of nude mice 40 days after the first injection. Histo logical analysis of the injected nodules revealed that the HuIFN beta gene transfection induced apoptosis of the human melanoma cells. These data sugg est that transfection of the HuIFNP gene using cationic liposomes is a prom ising candidate for gene therapy of human melanoma, (C) 2001 Lippincott Wil liams & Wilkins.