Role of RBP2-Induced ER and IGF1R-ErbB Signaling in Tamoxifen Resistance in Breast Canceropen access
- Authors
- Choi, Hee-Joo; Joo, Hyeong-Seok; Won, Hee-Young; Min, Kyueng-Whan; Kim, Hyung-Yong; Son, Taekwon; Oh, Young-Ha; Lee, Jeong-Yeon; Kong, Gu
- Issue Date
- Apr-2018
- Publisher
- OXFORD UNIV PRESS INC
- Citation
- JNCI-JOURNAL OF THE NATIONAL CANCER INSTITUTE, v.110, no.4, pp.400 - 410
- Indexed
- SCIE
SCOPUS
- Journal Title
- JNCI-JOURNAL OF THE NATIONAL CANCER INSTITUTE
- Volume
- 110
- Number
- 4
- Start Page
- 400
- End Page
- 410
- URI
- https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/150321
- DOI
- 10.1093/jnci/djx207
- ISSN
- 0027-8874
- Abstract
- Background: Despite the benefit of endocrine therapy, acquired resistance during or after treatment still remains a major challenge in estrogen receptor (ER)-positive breast cancer. We investigated the potential role of histone demethylase retinoblastoma-binding protein 2 (RBP2) in endocrine therapy resistance of breast cancer. Methods: Survival of breast cancer patients according to RBP2 expression was analyzed in three different breast cancer cohorts including METABRIC (n = 1980) and KM plotter (n = 1764). RBP2-mediated tamoxifen resistance was confirmed by in vitro sulforhodamine B (SRB) colorimetric, colony-forming assays, and in vivo xenograft models (n = 8 per group). RNA-seq analysis and receptor tyrosine kinase assay were performed to identify the tamoxifen resistance mechanism by RBP2. All statistical tests were two-sided. Results: RBP2 was associated with poor prognosis to tamoxifen therapy in ER-positive breast cancer (P = .04 in HYU cohort, P = .02 in KM plotter, P = .007 in METABRIC, log-rank test). Furthermore, RBP2 expression was elevated in patients with tamoxifen-resistant breast cancer (P = .04, chi-square test). Knockdown of RBP2 conferred tamoxifen sensitivity, whereas overexpression of RBP2 induced tamoxifen resistance in vitro and in vivo (MCF7 xenograft: tamoxifen-treated control, mean [SD] tumor volume = 70.8 [27.9] mm(3), vs tamoxifen-treated RBP2, mean [SD] tumor volume = 387.9 [85.1] mm(3), P < .001). Mechanistically, RBP2 cooperated with ER co-activators and corepressors and regulated several tamoxifen resistance-associated genes, including NRIP1, CCND1, and IGFBP4 and IGFBP5. Furthermore, epigenetic silencing of IGFBP4/5 by RBP2-ER-NRIP1- HDAC1 complex led to insulin-like growth factor-1 receptor (IGF1R) activation. RBP2 also increased IGF1R-ErbB crosstalk and subsequent PI3K-AKT activation via demethylase activity-independent ErbB protein stabilization. Combinational treatment with tamoxifen and PI3K inhibitor could overcome RBP2-mediated tamoxifen resistance (RBP2-overexpressing cells: % cell viability [SD], tamoxifen = 89.0 [3.8]%, vs tamoxifen with BKM120 = 41.3 [5.6]%, P < .001). Conclusions: RBP2 activates ER-IGF1R-ErbB signaling cascade in multiple ways to induce tamoxifen resistance, suggesting that RBP2 is a potential therapeutic target for ER-driven cancer.
- Files in This Item
-
Go to Link
- Appears in
Collections - 서울 의과대학 > 서울 병리학교실 > 1. Journal Articles
![qrcode](https://api.qrserver.com/v1/create-qr-code/?size=55x55&data=https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/150321)
Items in ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.