title: Cancer immunotherapy: the role regulatory T cells play and what can be done to overcome their inhibitory effects.
abstract: Since multiple lines of experimental and clinical data clearly identified regulatory T cells as an integral part of the immune response, these cells have become a major focus of investigation in tumor immunology. Regulatory T cells are in place to dampen ongoing immune responses and to prevent autoimmunity, but they also have profound effects in blocking therapeutic anti-tumor activity. Therefore regulatory T cells are seen as a major hurdle that must be overcome in order for cancer immunotherapy to reach its therapeutic potential. Regulatory T cells are heterogeneous with sub-populations that exhibit distinct functional features. Here we will review the individual sub-populations in regards to their mode of action and their potential impact on blocking anti-tumor immunity. Approaches to measure function and frequency of regulatory T cells in model systems and clinical trails will be discussed. Finally, we will describe possible ways to interfere with regulatory T cell-mediated immune suppression with the focus on recent pre-clinical and clinical findings.
authors.affiliation: Robert W. Franz Cancer Research Center, Earle. A. Chiles Research Institute, 4805 NE Glisan Street, Portland, OR 97213, USA.
authors.forename: Ulf
authors.initials: U
authors.lastname: Petrausch
authors.forename: Christian H
authors.initials: CH
authors.lastname: Poehlein
authors.forename: Shawn M
authors.initials: SM
authors.lastname: Jensen
authors.forename: Chris
authors.initials: C
authors.lastname: Twitty
authors.forename: James A
authors.initials: JA
authors.lastname: Thompson
authors.forename: Ilka
authors.initials: I
authors.lastname: Assmann
authors.forename: Sachin
authors.initials: S
authors.lastname: Puri
authors.forename: Michael G
authors.initials: MG
authors.lastname: LaCelle
authors.forename: Tarsem
authors.initials: T
authors.lastname: Moudgil
authors.forename: Levi
authors.initials: L
authors.lastname: Maston
authors.forename: Kevin
authors.initials: K
authors.lastname: Friedman
authors.forename: Sarah
authors.initials: S
authors.lastname: Church
authors.forename: Elisa
authors.initials: E
authors.lastname: Cardenas
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Haley
authors.forename: Edwin B
authors.initials: EB
authors.lastname: Walker
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Akporiaye
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Weinberg
authors.forename: Sidney
authors.initials: S
authors.lastname: Rosenheim
authors.forename: Todd S
authors.initials: TS
authors.lastname: Crocenzi
authors.forename: Hong-Ming
authors.initials: HM
authors.lastname: Hu
authors.forename: Brendan D
authors.initials: BD
authors.lastname: Curti
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Urba
authors.forename: Bernard A
authors.initials: BA
authors.lastname: Fox
mesh_terms: D000818:Animals; D019496:Cancer Vaccines / Q000276:immunology; D002986:Clinical Trials as Topic; D006801:Humans; D007108:Immune Tolerance; D007167:Immunotherapy; D009369:Neoplasms / Q000276:immunology* / Q000628:therapy*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D019496:Cancer Vaccines
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