title: Macrophages, Inflammation, and Lung Cancer.
abstract: Lung cancer is the leading cause of cancer mortality worldwide, and at only 18%, it has one of the lowest 5-year survival rates of all malignancies. With its highly complex mutational landscape, treatment strategies against lung cancer have proved largely ineffective. However with the recent success of immunotherapy trials in lung cancer, there is renewed enthusiasm in targeting the immune component of tumors. Macrophages make up the majority of the immune infiltrate in tumors and are a key cell type linking inflammation and cancer. Although the mechanisms through which inflammation promotes cancer are not fully understood, two connected hypotheses have emerged: an intrinsic pathway, driven by genetic alterations that lead to neoplasia and inflammation, and an extrinsic pathway, driven by inflammatory conditions that increase cancer risk. Here, we discuss the contribution of macrophages to these pathways and subsequently their roles in established tumors. We highlight studies investigating the association of macrophages with lung cancer prognosis and discuss emerging therapeutic strategies for targeting macrophages in the tumor microenvironment.
authors.affiliation: Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada.
authors.forename: Emma M
authors.initials: EM
authors.lastname: Conway
authors.affiliation: Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada.
authors.forename: Larissa A
authors.initials: LA
authors.lastname: Pikor
authors.affiliation: Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada.
authors.forename: Sonia H Y
authors.initials: SH
authors.lastname: Kung
authors.affiliation: Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada.
authors.forename: Melisa J
authors.initials: MJ
authors.lastname: Hamilton
authors.affiliation: Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada.
authors.forename: Stephen
authors.initials: S
authors.lastname: Lam
authors.affiliation: Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada.
authors.forename: Wan L
authors.initials: WL
authors.lastname: Lam
authors.affiliation: Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada.
authors.forename: Kevin L
authors.initials: KL
authors.lastname: Bennewith
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis; D002986:Clinical Trials as Topic; D018450:Disease Progression; D006801:Humans; D007167:Immunotherapy / Q000379:methods*; D007249:Inflammation / Q000209:etiology*; D008175:Lung Neoplasms / Q000276:immunology / Q000401:mortality / Q000628:therapy*; D008264:Macrophages / Q000276:immunology*; D010641:Phenotype; D011379:Prognosis; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor
keywords: immunosuppression; inflammation; lung cancer; tumor progression; tumor-associated macrophages