Cancer is a polygenic disorder that involves mutations in both tumor suppressor genes and oncogenes. However, a large body of preclinical data suggests that cancer growth can be halted or reversed by treatment with gene transfer vectors carrying a single growth-inhibitory or pro-apoptotic gene or a gene that can recruit anti-tumor immune responses.

Viral vectors recently used in laboratory and clinical uses are based on RNA and DNA viruses that process very different genomic structures and host ranges. Certain viruses have been selected as gene delivery vehicles because of their ability to carry foreign genes and their ability to efficiently deliver these genes associated with effective gene expression.

These are the main reasons why viral vectors derived from retroviruses, adenoviruses, adeno-associated viruses, herpesviruses, and poxviruses are used in more than 70% of clinical gene therapy trials worldwide.

Despite the challenges, gene therapy for cancer with viruses is a promising field in oncology, and several research and clinical trials are currently being conducted to develop and improve this technology. With continued advances in biotechnology, gene therapy is expected to become an available treatment option for more types of cancer in the future.