LSD1 去甲基化的 LINC01134 通过 SP1 诱导的 p62 转录赋予 HCC 对奥沙利铂的耐药性。

LSD1-Demethylated LINC01134 Confers Oxaliplatin Resistance Through SP1-Induced p62 Transcription in HCC.

机构信息

Department of Infectious Diseases, the Third Hospital of Hebei Medical University, Shijiazhuang, China.

Department of Genetic Engineering, Beijing Institute of Biotechnology, Beijing, China.

出版信息

Hepatology. 2021 Dec;74(6):3213-3234. doi: 10.1002/hep.32079. Epub 2021 Oct 5.

DOI:10.1002/hep.32079

PMID:34322883

Abstract

BACKGROUND AND AIMS

Oxaliplatin (OXA) is one of the most common chemotherapeutics in advanced hepatocellular carcinoma (HCC), the resistance of which poses a big challenge. Long noncoding RNAs (lncRNAs) play vital roles in chemoresistance. Therefore, elucidating the underlying mechanisms and identifying predictive lncRNAs for OXA resistance is needed urgently.

METHODS

RNA sequencing (RNA-seq) and fluorescence in situ hybridization (FISH) were used to investigate the OXA-resistant (OXA-R) lncRNAs. Survival analysis was performed to determine the clinical significance of homo sapiens long intergenic non-protein-coding RNA 1134 (LINC01134) and p62 expression. Luciferase, RNA immunoprecipitation (RIP), chromatin immunoprecipitation (ChIP), and chromatin isolation by RNA purification (ChIRP) assays were used to explore the mechanisms by which LINC01134 regulates p62 expression. The effects of LINC01134/SP1/p62 axis on OXA resistance were evaluated using cell viability, apoptosis, and mitochondrial function and morphology analysis. Xenografts were used to estimate the in vivo regulation of OXA resistance by LINC01134/SP1/p62 axis. ChIP, cell viability, and xenograft assays were used to identify the demethylase for LINC01134 up-regulation in OXA resistance.

RESULTS

LINC01134 was identified as one of the most up-regulated lncRNAs in OXA-R cells. Higher LINC01134 expression predicted poorer OXA therapeutic efficacy. LINC01134 activates anti-oxidative pathway through p62 by recruiting transcription factor SP1 to the p62 promoter. The LINC01134/SP1/p62 axis regulates OXA resistance by altering cell viability, apoptosis, and mitochondrial homeostasis both in vitro and in vivo. Furthermore, the demethylase, lysine specific demethylase 1 (LSD1) was responsible for LINC01134 up-regulation in OXA-R cells. In patients with HCC, LINC01134 expression was positively correlated with p62 and LSD1 expressions, whereas SP1 expression positively correlated with p62 expression.

CONCLUSIONS

LSD1/LINC01134/SP1/p62 axis is critical for OXA resistance in HCC. Evaluating LINC01134 expression in HCC will be effective in predicting OXA efficacy. In treatment-naive patients, targeting the LINC01134/SP1/p62 axis may be a promising strategy to overcome OXA chemoresistance.

摘要

背景与目的

奥沙利铂（OXA）是晚期肝细胞癌（HCC）中最常用的化疗药物之一，其耐药性是一个巨大的挑战。长链非编码 RNA（lncRNA）在化疗耐药中发挥着重要作用。因此，迫切需要阐明潜在的机制并确定预测 OXA 耐药的 lncRNA。

方法

使用 RNA 测序（RNA-seq）和荧光原位杂交（FISH）来研究奥沙利铂耐药（OXA-R）lncRNAs。进行生存分析以确定人类长非蛋白编码 RNA 1134（LINC01134）和 p62 表达的临床意义。使用荧光素酶报告基因检测、RNA 免疫沉淀（RIP）、染色质免疫沉淀（ChIP）和 RNA 纯化的染色质分离（ChIRP）实验来探讨 LINC01134 调节 p62 表达的机制。使用细胞活力、凋亡、线粒体功能和形态分析评估 LINC01134/SP1/p62 轴对 OXA 耐药的影响。使用异种移植评估 LINC01134/SP1/p62 轴对体内 OXA 耐药的调节作用。使用 ChIP、细胞活力和异种移植实验鉴定 OXA 耐药中 LINC01134 上调的去甲基酶。

结果

LINC01134 被鉴定为 OXA-R 细胞中上调最明显的 lncRNA 之一。较高的 LINC01134 表达预示着 OXA 治疗效果较差。LINC01134 通过招募转录因子 SP1 到 p62 启动子，通过 p62 激活抗氧化途径。LINC01134/SP1/p62 轴通过改变细胞活力、凋亡和线粒体动态平衡，在体外和体内均调节 OXA 耐药。此外，去甲基酶赖氨酸特异性去甲基酶 1（LSD1）负责 OXA-R 细胞中 LINC01134 的上调。在 HCC 患者中，LINC01134 的表达与 p62 和 LSD1 的表达呈正相关，而 SP1 的表达与 p62 的表达呈正相关。