Background: Cationic liposomes containing the human interferon beta (HuIFNbeta) gene (IAB-1) was used for the clinical trial for glioma patients. HuIFNbeta gene therapy showed much higher anti-tumor activity compared with the administration of HuIFNbeta protein for melanoma. These results suggest that HuIFNbeta gene therapy is an attractive strategy for the treatment of melanoma.
Methods: Stage IV or III melanoma patients with cutaneous or subcutaneous metastatic lesions were enrolled in this pilot study. IAB-1 was dissolved by sterile PBS at a concentration of 30 microg DNA/ml and was injected into cutaneous or subcutaneous metastatic nodules three times a week for 2 weeks and the effect on the injected and non-injected metastatic lesions was evaluated.
Results: Clinical responses were as follows (five patients): mixed response (MR) and no change in each one patient, and progressive disease in three patients. In the MR patient, the IAB-1 injected lesion disappeared clinically and histopathologically and one-half of IAB-1 non-injected skin metastases were transiently inflamed and mostly regressed. In the responded non-injected lesions of this patient, histopathologically, infiltration of CD4 positive T cells was observed around the melanoma cells in the dermis, which expressed the HLA-Class II antigen. Adverse events due to this gene therapy were not recognized in any of the patients.
Conclusions: The efficacy of this gene therapy was generally insufficient; however, some immunological responses were recognized in one patient. No adverse events were observed. HuIFNbeta gene therapy could be an attractive strategy for treatment of a variety of malignancies, including melanoma, though some modifications should be required.