Excellent new paper: Cancer immunotherapy: how low-level ionizing radiation can play a key role

Excellent new paper: Cancer immunotherapy: how low-level ionizing radiation can play a key role

See the new, open-access, review paper, just received (attached).  Includes 222 good references; looks comprehensive and convincing.  Online 2017 Mar 30.

https://www.ncbi.nlm.nih.gov/labs/articles/28361232/

https://link.springer.com/article/10.1007%2Fs00262-017-1993-z

http://download.springer.com/static/pdf/695/art%253A10.1007%252Fs00262-017-1993-z.pdf?originUrl=http%3A%2F%2Flink.springer.com%2Farticle%2F10.1007%2Fs00262-017-1993-z&token2=exp=1491322675~acl=%2Fstatic%2Fpdf%2F695%2Fart%25253A10.1007%25252Fs00262-017-1993-z.pdf%3ForiginUrl%3Dhttp%253A%252F%252Flink.springer.com%252Farticle%252F10.1007%252Fs00262-017-1993-z*~hmac=6b6d1d4a758a5b193aefb3665080678bb2d1ca663ed339fe69deff466d99787d

Cancer immunotherapy: how low-level ionizing radiation can play a key role

By Marek K. Janiak · Marta Wincenciak · Aneta Cheda · Ewa M. Nowosielska · Edward J. Calabrese

Abstract The cancer immunoediting hypothesis assumes that the immune system guards the host against the incipient cancer, but also “edits” the immunogenicity of surviving neoplastic cells and supports remodeling of tumor microenvironment towards an immunosuppressive and pro-neoplastic state. Local irradiation of tumors during standard radiotherapy, by killing neoplastic cells and generating inflammation, stimulates anti-cancer immunity and/or partially reverses cancer-promoting immunosuppression. These effects are induced by moderate (0.1–2.0 Gy) or high (>2 Gy) doses of ionizing radiation which can also harm normal tissues, impede immune functions, and increase the risk of secondary neoplasms. In contrast, such complications do not occur with exposures to low doses (≤0.1 Gy for acute irradiation or ≤0.1 mGy/min dose rate for chronic exposures) of low-LET ionizing radiation. Furthermore, considerable evidence indicates that such low-level radiation (LLR) exposures retard the development of neoplasms in humans and experimental animals. Here, we review immunosuppressive mechanisms induced by growing tumors as well as immunomodulatory effects of LLR evidently or likely associated with cancer-inhibiting outcomes of such exposures. We also offer suggestions how LLR may restore and/or stimulate effective anti-tumor immunity during the more advanced stages of carcinogenesis. We postulate that, based on epidemiological and experimental data amassed over the last few decades, whole- or half-body irradiations with LLR should be systematically examined for its potential to be a viable immunotherapeutic treatment option for patients with systemic cancer.

Keywords Low-level radiation · Carcinogenesis · Immune suppression · Radio-immunotherapy