title: CD73 on tumor cells impairs antitumor T-cell responses: a novel mechanism of tumor-induced immune suppression.
abstract: CD73, originally defined as a lymphocyte differentiation antigen, is thought to function as a cosignaling molecule on T lymphocytes and an adhesion molecule that is required for lymphocyte binding to endothelium. We show here that CD73 is widely expressed on many tumor cell lines and is upregulated in cancerous tissues. Because the ecto-5'-nucleotidase activity of CD73 catalyzes AMP breakdown to immunosuppressive adenosine, we hypothesized that CD73-generated adenosine prevents tumor destruction by inhibiting antitumor immunity. We confirmed this hypothesis by showing that combining tumor CD73 knockdown and tumor-specific T-cell transfer cured all tumor-bearing mice. In striking contrast, there was no therapeutic benefit of adoptive T-cell immunotherapy in mice bearing tumors without CD73 knockdown. Moreover, blockade of the A2A adenosine receptor with a selective antagonist also augmented the efficacy of adoptive T-cell therapy. These findings identify a potential mechanism for CD73-mediated tumor immune evasion and point to a novel cancer immunotherapy strategy by targeting the enzymatic activity of tumor CD73.
authors.affiliation: Cancer Therapy and Research Center, Department of Medicine, University of Texas Health Science Center, San Antonio, Texas 78229, USA.
authors.forename: Dachuan
authors.initials: D
authors.lastname: Jin
authors.forename: Jie
authors.initials: J
authors.lastname: Fan
authors.forename: Long
authors.initials: L
authors.lastname: Wang
authors.forename: Linda F
authors.initials: LF
authors.lastname: Thompson
authors.forename: Aijie
authors.initials: A
authors.lastname: Liu
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Daniel
authors.forename: Tahiro
authors.initials: T
authors.lastname: Shin
authors.forename: Tyler J
authors.initials: TJ
authors.lastname: Curiel
authors.forename: Bin
authors.initials: B
authors.lastname: Zhang
mesh_terms: D015720:5'-Nucleotidase / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D000241:Adenosine / Q000037:antagonists & inhibitors / Q000276:immunology; D058917:Adenosine A2 Receptor Antagonists; D000818:Animals; D017209:Apoptosis / Q000276:immunology; D005260:Female; D005434:Flow Cytometry; D016219:Immunotherapy, Adoptive / Q000379:methods; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010051:Ovarian Neoplasms / Q000276:immunology* / Q000473:pathology / Q000628:therapy; D011743:Pyrimidines / Q000494:pharmacology; D034741:RNA, Small Interfering / Q000235:genetics; D043705:Receptor, Adenosine A2A / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D014230:Triazoles / Q000494:pharmacology
chemical_list: C098657:5-amino-7-(2-phenylethyl)-2-(2-furyl)pyrazolo(4,3-e)-1,2,4-triazolo(1,5-c)pyrimidine; D058917:Adenosine A2 Receptor Antagonists; D011743:Pyrimidines; D034741:RNA, Small Interfering; D043705:Receptor, Adenosine A2A; D014230:Triazoles; D015720:5'-Nucleotidase; D000241:Adenosine