AbstractRapid advances in cancer gene therapy are driven by an explosive development of gene transfer technology and a strong demand for seeking alternatives to unsatisfactory conventional cancer therapies. Discovery of the genetic basis of cancer has indicated that cancer is a disease of genes. Among a variety of approaches to gene therapy of cancer, antisense oncogene and tumor suppressor gene therapy of cancer are the two strategies that aim at correcting genetic disorders of cancer through suppression of the abnormal expression of the proliferative genes. The potential effectiveness of these approaches is promised by their precise targeting at the mechanisms of the disease. Examples of several preclinical studies of these types of approaches that led to the approval of clinical trials are reviewed. Limitation and future development of these approaches are also discussed.