PO.ET03.01 · 实验与分子治疗
ARNT2和AhR促进对HIF2a抑制剂belzutifan的耐药
ARNT2 and AhR promote resistance to HIF2a inhibitor belzutifan
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
引言：von Hippel-Lindau（VHL）肿瘤抑制基因在所有VHL病相关肿瘤中以及在超过90%的散发性肾细胞癌和中枢神经系统血管母细胞瘤中失活。VHL缺失的细胞组成性地高水平表达致癌转录因子缺氧诱导因子（HIF1a和HIF2a）。HIF2a属于bHLH-PAS蛋白家族，它是缺氧的感受器，并与多种衔接性bHLH-PAS蛋白形成专性核异二聚体。HIF-ARNT异二聚体与缺氧诱导基因启动子中的HRE序列结合。Belzutifan是一种同类首创的口服药物，可破坏HIF2a与ARNT（HIF1b）的相互作用，并抑制驱动VHL肿瘤生长的HIF2a靶基因的表达。已检测到对该药物的从头耐药和获得性耐药。
实验步骤：在此我们表明，bHLH-PAS蛋白ARNT2的核水平影响RCC对belzutifan的敏感性或耐药性。在人癌细胞系中敲低或敲除ARNT2使细胞对belzutifan产生耐药，而过表达外源性ARNT2则在体外增加细胞对belzutifan抗增殖作用的敏感性。Belzutifan优先破坏ARNT-HIF2a而非ARNT2-HIF2a异二聚体，其作用取决于ARNT-HIF2a的水平。ARNT2敲除细胞的bulk RNA测序的全局基因表达在PCA图分析中与HIF2a过表达细胞聚在一起，并显著诱导了功能上涉及AhR（芳香烃受体）感受器蛋白的解毒信号。用belzutifan或AhR配体处理细胞会根据感受器和衔接分子的核水平重新排列这些程序。我们表明，belzutifan和/或AhR激动剂FICZ处理增加了AhR-Luc活性和CYP1A1（AhR的靶基因）的表达，并影响了对belzutifan的敏感性。
总结：我们的数据提示，提高ARNT2细胞水平的策略可能有助于对抗对belzutifan的从头或获得性耐药。
查看英文原文 English abstract
Introduction: The von Hippel-Lindau ( VHL ) tumor suppressor gene is inactivated in all VHL disease-associated tumors and in more than 90% of sporadic renal cell carcinomas and central nervous system hemangioblastomas. VHL-depleted cells constitutively express high levels of the oncogenic transcription factors Hypoxia-Inducible Factors (HIF1a and HIF2a). HIF2a belongs to the family of bHLH-PAS proteins, it is a sensor of hypoxia and forms nuclear obligatory heterodimers with several adaptor bHLH-PAS protein. HIF-ARNT heterodimers bind HRE sequences in the promoters of hypoxia inducible genes. Belzutifan, a first in class oral medication, disrupt the interaction of HIF2a with ARNT (HIF1b) and suppresses HIF2a target genes expression that drive VHL tumor growth. De novo and acquired resistance to this medication has been detected.
Experimental procedures: Here we show that the nuclear levels of the bHLH-PAS protein ARNT2 contribute to the sensitivity or resistance of RCC to belzutifan. Knock down or knock out of ARNT2 in human cancer cell lines renders the cells resistant to belzutifan, while overexpression of exogenous ARNT2 increases the sensitivity of the cells to the anti-proliferative effect of belzutifan in vitro. Belzutifan disrupts preferentially the ARNT-HIF2a but not the ARNT2-HIF2a heterodimers and its effect depends on levels of ARNT-HIF2a. The global gene expression from bulk RNA sequencing in ARNT2 knock out cells clustered with HIF2a overexpression cells in PCA plot analysis and significantly induced detoxification signaling that functionally involved in AhR (Aryl hydrocarbon Receptor) sensor protein. Treatment of cells with belzutifan or an AhR ligand re-arranges these programs based on the nuclear levels of sensor and adaptor molecules. We show that belzutifan and/or AhR agonist, FICZ treatment increased AhR-Luc activity and CYP1A1 expression, which is a target gene of AhR, and affected to the sensitivity to belzutifan.
Summary: Our data suggest that strategies to increase ARNT2 cellular levels may help in combating de novo or acquired resistance to belzutifan.
利益披露 Disclosure
D. Min, None..
S. Poudel, None..
R. Morris, None..
I. Mitsiades, None..
M. Perez, None..
E. Zaniewski, None..
T. Shioda, None..
E. Rheinbay, None..
M. Motamedi, None..
W. Haas, None..
O. Iliopoulos, None.