研究揭示乳腺癌患者中FOXA1突變的功能
作者:
小柯機器人發布時間:2020/9/4 20:15:15
美國紀念斯隆-凱特琳癌症中心Maurizio Scaltriti和約翰霍普金斯醫學院Eneda Toska小組合作取得一項新突破。他們發現乳腺癌患者中FOXA1突變導致了不同染色質構象並影響對治療的反應。 該項研究成果在線發表在2020年9月3日的《癌細胞》上。
使用臨床基因組隊列以及乳腺癌模型,研究人員發現FOXA1突變與對芳香化酶抑制劑反應較低相關。從機制上講,Wing2突變在雌激素刺激下導致ER位點染色質結合增加,並且在不影響染色質可及性的情況下增強了雌激素受體(ER)介導的轉錄。相比之下,SY242CS可導致新特徵的產生,包括賦予其打開不同染色質區域的能力並激活可變的順反組和轉錄組。
結構建模顯示SY242CS導致構象變化,該構象變化介導與非典型DNA結構域的穩定結合。綜上所述,該研究結果提供了對FOXA1突變如何幹擾其功能以促進癌症進展和對治療反應的見解。
研究人員介紹,先鋒轉錄因子FOXA1的突變是ER+乳腺癌的標誌。在約5000名乳腺癌患者中檢測FOXA1發現了Wing2區的幾個熱點突變,以及位於第三條β鏈的乳腺癌特異性突變SY242CS。
附:英文原文
Title: FOXA1 Mutations Reveal Distinct Chromatin Profiles and Influence Therapeutic Response in Breast Cancer
Author: Amaia Arruabarrena-Aristorena, Jesper L.V. Maag, Srushti Kittane, Yanyan Cai, Wouter R. Karthaus, Erik Ladewig, Jane Park, Srinivasaraghavan Kannan, Lorenzo Ferrando, Emiliano Cocco, Sik Y. Ho, Daisylyn S. Tan, Mirna Sallaku, Fan Wu, Barbara Acevedo, Pier Selenica, Dara S. Ross, Matthew Witkin, Charles L. Sawyers, Jorge S. Reis-Filho, Chandra S. Verma, Ralf Jauch, Richard Koche, José Baselga, Pedram Razavi, Eneda Toska, Maurizio Scaltriti
Issue&Volume: 2020-09-03
Abstract: Mutations in the pioneer transcription factor FOXA1 are a hallmark of estrogen receptor-positive(ER+) breast cancers. Examining FOXA1 in ~5,000 breast cancer patients identifies several hotspot mutations in the Wing2region and a breast cancer-specific mutation SY242CS, located in the third β strand.Using a clinico-genomically curated cohort, together with breast cancer models, wefind that FOXA1 mutations associate with a lower response to aromatase inhibitors. Mechanistically,Wing2 mutations display increased chromatin binding at ER loci upon estrogen stimulation,and an enhanced ER-mediated transcription without changes in chromatin accessibility.In contrast, SY242CS shows neomorphic properties that include the ability to opendistinct chromatin regions and activate an alternative cistrome and transcriptome.Structural modeling predicts that SY242CS confers a conformational change that mediatesstable binding to a non-canonical DNA motif. Taken together, our results provide insightsinto how FOXA1 mutations perturb its function to dictate cancer progression and therapeutic response.
DOI: 10.1016/j.ccell.2020.08.003
Source: https://www.cell.com/cancer-cell/fulltext/S1535-6108(20)30414-1