Impaired IFN-α production and the risk of cancer development

Type I interferons (IFNs) play a pivotal role not only in antiviral immunity but also in the surveillance of cancer development. In order to quantify the critical function of type I IFNs in the suppression of human cancer development, IFN-alpha production in response to Sendai virus stimulation has been compared between healthy control subjects and hepatitis C virus (HCV)-infected patients, the latter being an ideal population for long-term monitoring of cancer development. Data for IFN-alpha production were obtained retrospectively over a 17-year period by examining medical records in a study population of 2315 individuals, of which 112 healthy controls and 20 HCV-infected patients were selected. Sixty percent of the HCV-infected patients had impaired or declining IFN-alpha production, in comparison to 17% in the healthy control group. Mean IFN-alpha levels were lower in patients who developed hepatocellular carcinoma than in the HCV-infected patients who remained cancer free. Our findings suggest that impairment of IFN-alpha production may be linked to an increased cancer risk and that dysfunction of the IFN system is associated with some types of cancer. Therefore, periodic assessment and quantification of IFN-alpha production can be a potential test for the early detection of cancer in humans.