Journal Article

Immune response to RB1-regulated senescence limits radiation-induced osteosarcoma formation

Pang, Puiyi, Cullinane, Carleen, Kansara, Maya, Ellul, Jason, Hicks, Rod, Kuijjer, Marieke L, Smyth, Mark J, Leong, Huei San, Haynes, Nicole M, Lin, Dan Mei, Cleton-Jansen, Anne-Marie, Thomas, David M, Popkiss, Sophie, Hinds, Philip W, Garsed, Dale W, Walkley, Carl R

2013

Overview

Ionizing radiation (IR) and germline mutations in the retinoblastoma tumor suppressor gene (RB1) are the strongest risk factors for developing osteosarcoma. Recapitulating the human predisposition, we found that Rb1+/- mice exhibited accelerated development of IR-induced osteosarcoma, with a latency of 39 weeks. Initial exposure of osteoblasts to carcinogenic doses of IR in vitro and in vivo induced RB1-dependent senescence and the expression of a panel of proteins known as senescence-associated secretory phenotype (SASP), dominated by IL-6. RB1 expression closely correlated with that of the SASP cassette in human osteosarcomas, and low expression of both RB1 and the SASP genes was associated with poor prognosis. In vivo, IL-6 was required for IR-induced senescence, which elicited NKT cell infiltration and a host inflammatory response. Mice lacking IL-6 or NKT cells had accelerated development of IR-induced osteosarcomas. These data elucidate an important link between senescence, which is a cell-autonomous tumor suppressor response, and the activation of host-dependent cancer immunosurveillance. Our findings indicate that overcoming the immune response to senescence is a rate-limiting step in the formation of IR-induced osteosarcoma.

• Publisher: American Society for Clinical Investigation
• Subject: Animals / Biomedical research / Bone cancer / Bone Neoplasms - etiology / Bone Neoplasms - genetics / Bone Neoplasms - immunology / Bone Neoplasms - pathology / Calcium Radioisotopes - toxicity / Cellular Senescence - physiology / Cytokines - physiology / Gene expression / Genes, Retinoblastoma / Humans / Immunologic Surveillance / Intercellular Signaling Peptides and Proteins - physiology / Interleukin-6 - deficiency / Interleukin-6 - physiology / Kinases / Mice / Mice, Inbred C57BL / Natural Killer T-Cells - immunology / Neoplasm Proteins - antagonists & inhibitors / Neoplasm Proteins - physiology / Neoplasm Transplantation - immunology / Neoplasms, Radiation-Induced - etiology / Neoplasms, Radiation-Induced - genetics / Neoplasms, Radiation-Induced - immunology / Neoplasms, Radiation-Induced - pathology / Osteoblasts - pathology / Osteosarcoma - etiology / Osteosarcoma - genetics / Osteosarcoma - immunology / Osteosarcoma - pathology / Phenotype / Prognosis / Proteins / Retinoblastoma Protein - antagonists & inhibitors / Retinoblastoma Protein - physiology / RNA Interference / Scholarships & fellowships / Software / Statistical methods / Survival analysis / Tumors