Immunosurveillance of Tumors
Tumor immunosurveillance is defined as an extrinsic tumor-suppressive mechanism whereby the immune system identifies and eliminates cancerous and/or precancerous cells.
Development of the Cancer Immunosurveillance Theory
The concept of cancer immunosurveillance was first proposed by Frank Macfarlane Burnet and Lewis Thomas in 1957 who speculated that lymphocytes acted as sentinels in recognizing and eliminating continuously arising, nascent-transformed cells before they manifested disease. However, this theory had been under a long-standing debate due to the absence of strong experimental data illustrating immunological eradication of cancerous lesions in vivo until late 1990s. Then, key findings from the first sets of experiments using mice with genetically defined mutations demonstrated that deficiencies in critical components of the immune system (effector molecules such as IFN-gamma and perforin; cellular compartments such as lymphocytes) increased the development of...