Prospects of cancer biotherapy.

Biotherapy became recognized as the fourth modality of cancer treatment applied after surgical treatment, radiotherapy and chemotherapy since the Biological Response Modifier (BRM) theory was proposed by Dr. Oldham in the 1980s (1). Cancer biotherapy is a therapeutic method that could prohibit the growth of tumors through mobilizing the host's immune system or via the effect of biological agents, thereby regulating the body's biological responses (2). Biotherapy is regarded as the most vigorous and promising strategy among the cancer multimodality treatments in this century due to its advantages of high safety and effectiveness as well as low side-effects (2-4). Treatment methods of biotherapy are emerging with the development of such subjects as immunology, cell biology and molecular biology. Currently, the main approaches of biotherapy include molecule targeted therapy, gene therapy and cell therapy.