title: IL4 limits the efficacy of tumor-targeted antibody therapy in a murine model.
abstract: Tumor-targeted antibody therapy has had a major impact on reducing morbidity and mortality in a wide range of cancers. Antibodies mediate their antitumor activity in part by activating immune effector cells; however, the tumor microenvironment (TME) is enriched with cellular and soluble mediators that actively suppress generation of antitumor immunity. Here, we investigate the potential of prospectively identifying and neutralizing an immunomodulatory soluble mediator within the TME to enhance therapeutic efficacy of the HER2-directed antibody trastuzumab. Using the D5-HER2 cell line and an immunocompetent human HER2 transgenic animal (hmHER2Tg) in which human HER2 is a self-antigen, we determined that IL4 was present in the TME and produced by both tumor and stromal cells. A siRNA-based screening approach identified STAT5A as a novel negative regulator of IL4 production by D5-HER2 tumor cells. Furthermore, IL4 neutralization using the anti-IL4 antibody 11B11 enhanced the efficacy of trastuzumab and modulated the TME. For example, IL4 neutralization resulted in reduced levels of myeloid chemoattractants CCL2, CCL11, and CXCL5 in the TME. Combination therapy with 11B11 and trastuzumab resulted in a reduction of tumor-infiltrating CD11b(+)CD206(+) myeloid cells compared with monotherapy. These data suggest that IL4 neutralization enhances the efficacy of trastuzumab by influencing the phenotype of myeloid cells within the TME and provide further rationale for combining tumor-targeted antibody therapy with agents that neutralize factors in the TME that suppress generation of productive antitumor immune responses.
authors.affiliation: Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, District of Columbia.
authors.forename: Rishi
authors.initials: R
authors.lastname: Surana
authors.affiliation: Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, District of Columbia.
authors.forename: Shangzi
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Pathology, Georgetown University Medical Center, Washington, District of Columbia.
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
authors.affiliation: Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, District of Columbia.
authors.forename: Sandra A
authors.initials: SA
authors.lastname: Jablonski
authors.affiliation: Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, District of Columbia. weinerl@georgetown.edu.
authors.forename: Louis M
authors.initials: LM
authors.lastname: Weiner
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology; D015153:Blotting, Western; D004797:Enzyme-Linked Immunosorbent Assay; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology; D006801:Humans; D007167:Immunotherapy / Q000379:methods; D015847:Interleukin-4 / Q000096:biosynthesis / Q000276:immunology*; D051379:Mice; D008822:Mice, Transgenic; D060888:Real-Time Polymerase Chain Reaction; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000235:genetics; D050799:STAT5 Transcription Factor / Q000276:immunology; D000068878:Trastuzumab; D059016:Tumor Microenvironment / Q000187:drug effects / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D015847:Interleukin-4; D018719:Erb-b2 Receptor Tyrosine Kinases; D050799:STAT5 Transcription Factor; D000068878:Trastuzumab