PURPOSE: We have shown previously that tumor infiltration by FOXP3+ regulatory T cells (Treg) is associated with increased relapse and shorter survival of patients with both in situ and invasive breast cancer. Because estrogen regulates Treg numbers in mice and promotes the proliferation of human Tregs, we hypothesized that blocking estrogen receptor-alpha signaling would abrogate Tregs and be associated with response to hormonal therapy and increased survival. EXPERIMENTAL DESIGN: FOXP3+ Tregs were quantified in tumor samples collected at baseline by incisional biopsy and after 6 months at definitive surgery in 83 elderly breast cancer patients (T2-4 N0-1) enrolled in a randomized phase II trial based on 6 months of primary letrozole (2.5 mg/d) or 6 months of letrozole plus oral "metronomic" cyclophosphamide (50 mg/d). RESULTS: Treg number ranged from 0 to 380 (median, 30) before treatment and from 0 to 300 (median, 8) after treatment. There was a significant reduction in Tregs in letrozole and letrozole-cyclophosphamide patients (P < 0.0001 and P < 0.002, respectively) after treatment. Treg number at residual histology was inversely related with response (P < 0.03 and P = 0.50, respectively) and a greater Treg reduction was observed in responding patients (P < 0.03). CONCLUSION: This study suggests that aromatase inhibitors may have an indirect antitumor mechanism of action through reducing Tregs in breast tumors and may be of use in estrogen receptor-alpha-negative tumors in combination with immunotherapy approaches.
PURPOSE: We have shown previously that tumor infiltration by FOXP3+ regulatory T cells (Treg) is associated with increased relapse and shorter survival of patients with both in situ and invasive breast cancer. Because estrogen regulates Treg numbers in mice and promotes the proliferation of human Tregs, we hypothesized that blocking estrogen receptor-alpha signaling would abrogate Tregs and be associated with response to hormonal therapy and increased survival. EXPERIMENTAL DESIGN:FOXP3+ Tregs were quantified in tumor samples collected at baseline by incisional biopsy and after 6 months at definitive surgery in 83 elderly breast cancerpatients (T2-4 N0-1) enrolled in a randomized phase II trial based on 6 months of primary letrozole (2.5 mg/d) or 6 months of letrozole plus oral "metronomic" cyclophosphamide (50 mg/d). RESULTS: Treg number ranged from 0 to 380 (median, 30) before treatment and from 0 to 300 (median, 8) after treatment. There was a significant reduction in Tregs in letrozole and letrozole-cyclophosphamidepatients (P < 0.0001 and P < 0.002, respectively) after treatment. Treg number at residual histology was inversely related with response (P < 0.03 and P = 0.50, respectively) and a greater Treg reduction was observed in responding patients (P < 0.03). CONCLUSION: This study suggests that aromatase inhibitors may have an indirect antitumor mechanism of action through reducing Tregs in breast tumors and may be of use in estrogen receptor-alpha-negative tumors in combination with immunotherapy approaches.
Authors: Gaoping Zhao; Daniel J Moore; James I Kim; Kang Mi Lee; Matthew R O'Connor; Patrick E Duff; Maozhu Yang; Ji Lei; James F Markmann; Shaoping Deng Journal: Sci Transl Med Date: 2011-06-15 Impact factor: 17.956
Authors: Shona Hendry; Roberto Salgado; Thomas Gevaert; Prudence A Russell; Tom John; Bibhusal Thapa; Michael Christie; Koen van de Vijver; M V Estrada; Paula I Gonzalez-Ericsson; Melinda Sanders; Benjamin Solomon; Cinzia Solinas; Gert G G M Van den Eynden; Yves Allory; Matthias Preusser; Johannes Hainfellner; Giancarlo Pruneri; Andrea Vingiani; Sandra Demaria; Fraser Symmans; Paolo Nuciforo; Laura Comerma; E A Thompson; Sunil Lakhani; Seong-Rim Kim; Stuart Schnitt; Cecile Colpaert; Christos Sotiriou; Stefan J Scherer; Michail Ignatiadis; Sunil Badve; Robert H Pierce; Giuseppe Viale; Nicolas Sirtaine; Frederique Penault-Llorca; Tomohagu Sugie; Susan Fineberg; Soonmyung Paik; Ashok Srinivasan; Andrea Richardson; Yihong Wang; Ewa Chmielik; Jane Brock; Douglas B Johnson; Justin Balko; Stephan Wienert; Veerle Bossuyt; Stefan Michiels; Nils Ternes; Nicole Burchardi; Stephen J Luen; Peter Savas; Frederick Klauschen; Peter H Watson; Brad H Nelson; Carmen Criscitiello; Sandra O'Toole; Denis Larsimont; Roland de Wind; Giuseppe Curigliano; Fabrice André; Magali Lacroix-Triki; Mark van de Vijver; Federico Rojo; Giuseppe Floris; Shahinaz Bedri; Joseph Sparano; David Rimm; Torsten Nielsen; Zuzana Kos; Stephen Hewitt; Baljit Singh; Gelareh Farshid; Sibylle Loibl; Kimberly H Allison; Nadine Tung; Sylvia Adams; Karen Willard-Gallo; Hugo M Horlings; Leena Gandhi; Andre Moreira; Fred Hirsch; Maria V Dieci; Maria Urbanowicz; Iva Brcic; Konstanty Korski; Fabien Gaire; Hartmut Koeppen; Amy Lo; Jennifer Giltnane; Marlon C Rebelatto; Keith E Steele; Jiping Zha; Kenneth Emancipator; Jonathan W Juco; Carsten Denkert; Jorge Reis-Filho; Sherene Loi; Stephen B Fox Journal: Adv Anat Pathol Date: 2017-09 Impact factor: 3.875