title: Macrophage polarization at the crossroad between HIV-1 infection and cancer development.
abstract: Mononuclear phagocytes play a fundamental role in the tissue homeostasis and innate defenses against viruses and other microbial pathogens. In addition, they are likely involved in several steps of cancer development. Circulating monocytes and tissue macrophages are target cells of viral infections, including human cytomegalovirus, human herpes virus 8, and the HIV, and alterations of their functional and phenotypic properties are likely involved in many tissue-degenerative diseases, including atherosclerosis and cancer. Different tissue microenvironments as well as their pathological alterations can profoundly affect the polarization state of macrophages toward the extreme phenotypes conventionally termed M1 and M2. Thus, targeting disease-associated macrophages is considered a potential approach particularly in the context of cancer-associated tumor-associated macrophages, supporting malignant cell growth and progression toward a metastatic phenotype. Of note is the fact that tumor-associated macrophages isolated from established tumors display phenotypic and functional features similar to those of in vitro-derived M2-polarized cells. Concerning HIV-1 infection, viral eradication strategies in the context of combination antiretroviral therapy should also consider the possibility to deplete, at least transiently, certain mononuclear phagocytes subsets, although the possibility of distinguishing those that are either infected or pathogenically altered remains a goal of future research. In the present review, we will focus on the recent literature concerning the role of human macrophage polarization in viral infections and cancer.
authors.affiliation: AIDS Immunopathogenesis Unit, Division of Immunology, Transplantation and Infectious Diseases, San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Alfano
authors.forename: Francesca
authors.initials: F
authors.lastname: Graziano
authors.forename: Luca
authors.initials: L
authors.lastname: Genovese
authors.forename: Guido
authors.initials: G
authors.lastname: Poli
mesh_terms: D056704:Adaptive Immunity / Q000276:immunology / Q000502:physiology; D000818:Animals; D016764:Cell Polarity / Q000276:immunology* / Q000502:physiology; D018450:Disease Progression; D015658:HIV Infections / Q000276:immunology* / Q000503:physiopathology; D015497:HIV-1 / Q000276:immunology; D006801:Humans; D007113:Immunity, Innate / Q000276:immunology / Q000502:physiology; D008262:Macrophage Activation / Q000276:immunology*; D008264:Macrophages / Q000166:cytology* / Q000276:immunology; D051379:Mice; D009369:Neoplasms / Q000276:immunology* / Q000503:physiopathology; D010641:Phenotype; D012680:Sensitivity and Specificity
keywords: HIV; M1; M2; cancer; human cytomegalovirus; human herpes virus 8; macrophage; polarization