The Role of Interleukin 1β in the Pathogenesis of Lung Cancer

INTRODUCTION: Chronic inflammation is associated with an increased risk of several diseases, including cancer. A complex tumor microenvironment created and maintained by a range of cell types promotes tumor growth, angiogenesis, and metastasis. Inflammasomes, multicomplex cytosolic proteins, generate much of this inflammation, including the activation of the cytokine interleukin (IL)-1β. Inflammation generated by IL-1β is present in several disease states, including atherosclerosis, diabetes, and arthritis. IL-1β is activated when a specific inflammasome, nucleotide-binding domain–like receptor protein 3, induces cleavage of pro–IL-1β into its active form. Nucleotide-binding domain–like receptor protein 3 is up-regulated in lung cancer; IL-1β binds to its receptor and activates signaling pathways, including the MAPK, cyclooxygenase, and nuclear factor–κB pathways, leading to macrophage activation, intratumoral accumulation of immunosuppressive myeloid cells, and tumor growth, invasiveness, metastasis, and angiogenesis. Evidence suggests a role for IL-1β and some of its downstream effectors (e.g., IL-6, IL-8, C-reactive protein, cyclooxygenase-2) as prognostic markers in many malignancies, including lung cancer. METHODS: A phase III cardiovascular study of canakinumab, a human immunoglobulin Gk monoclonal antibody with high affinity and specificity for IL-1β, was conducted in patients who had a myocardial infarction. RESULTS: A subanalysis of this study found that treatment with canakinumab substantially reduced incident lung cancer and lung cancer mortality in a dose-dependent manner. CONCLUSIONS: A phase III trial is currently recruiting participants to evaluate canakinumab as adjuvant treatment versus placebo in patients with lung cancer. Other studies are investigating combinations of established antineoplastic agents and canakinumab in both early- and advanced-stage NSCLC.