In a study published recently in the British Journal of Cancer, a team of researchers from Kumamoto University (Kumamoto, Japan), have demonstrated that IL-6 suppresses oxidative stress as a way of controlling resistance to radiation in oral squamous cell carcinoma (OSCC).
The group analyzed the effects of IL-6 on radiosensitivity and DNA damage following X-ray irradiation on two OSCC cell lines and OSCC tissue samples with radioresistant cells. They demonstrated that increased levels of IL-6 resulted in suppressed radiation induced cell death and that blocking IL-6 signalling sensitized tumor cells to radiation.
Overall, the radio-resistant effects of IL-6 were associated with decreased DNA damage following radiation exposure. In addition, the team investigated the role of the Nrf2-antioxidant pathway and highlighted that IL-6 interacts with the Nrf2-antioxidant pathway in order to provide protection from radiation therapy to cancer cells.
One of research group leaders Hideki Nakayama (Kumamoto University) commented: “This interaction and the resulting protection from oxidative damage that we have discovered here is very interesting. We hope new therapies that target IL-6 will give us an advantage over many types of radiation-resistant cancers.”
Although they acknowledge that the in vitro nature of this study is a limitation, their initially promising results indicate that blocking IL-6 signalling in combination with conventional radiotherapy may yield better survival rates and treatment responses in patients with radio-resistant OSCC.
Matsuoka Y, Nakayama H, Yoshida R et al IL-6 controls resistance to radiation by suppressing oxidative stress via the Nrf2-antioxidant pathway in oral squamous cell carcinoma Br. J. Cancer (2016). Eureka press release www.eurekalert.org/pub_releases/2017-01/ku-rtr011317.php