RNF8在具有GTF2I/RARA融合的变异型急性早幼粒细胞白血病中导致全反式维甲酸（ATRA）耐药，而抑制泛素-蛋白酶体途径有助于逆转ATRA耐药。
RNF8 is responsible for ATRA resistance in variant acute promyelocytic leukemia with GTF2I/RARA fusion, and inhibition of the ubiquitin-proteasome pathway contributes to the reversion of ATRA resistance.
作者信息
Yan Wenzhe, Li Ji, Zhang Yang, Yin Yafei, Cheng Zhao, Wang Jiayi, Hu Guoyu, Liu Sufang, Wang Yewei, Xu Yunxiao, Peng Hongling, Zhang Guangsen
机构信息
1Department of Hematology, The Secong Xiangya Hospital, Central South University, Changsha, 410011 Hunan China.
2Department of Oncology, The Secong Xiangya Hospital, Central South University, Changsha, 410011 Hunan China.
出版信息
Cancer Cell Int. 2019 Apr 4;19:84. doi: 10.1186/s12935-019-0803-4. eCollection 2019.
BACKGROUND
- is a newly identified fusion gene in variant acute promyelocytic leukemia (APL) patients with t(7;17)(q11;q21). Clinical manifestation in the patient showed that it is a sort of ATRA-insensitive oncogene and is different from the classic - in terms of therapeutic reaction.
METHODS
To reveal the functional characteristics and regulating mechanism of the - fusion gene, we established a --transfected HL60 cell model and examined its sensitivity to ATRA by western blot, MTT assay, flow cytometry, and Wright-Giemsa staining. Coimmunoprecipitation and confocal microscopy were used to examine the binding of GTF2I-RARA and transcriptional corepressors. We also performed ChIP-seq to search for potential target genes. Immunoprecipitation, ubiquitination assay, western blot, luciferase assay, and real-time PCR were used to analyze the effects of RNF8 on RARA. Flow cytometry and Wright-Giemsa staining were used to study the effect of MG132 and ATRA on the --transfected HL60 cell model.
RESULT
We confirmed resistance of GTF2I-RARA to ATRA. Compared with -- has a higher affinity to HDAC3 under ATRA treatment. Using the ChIP-sequencing approach, we identified 221 - binding sites in model cells and found that the RING finger protein 8 (RNF8) is a target gene of -. RNF8 participates in disease progression and therapy resistance in APL with the - transcript. Elevated RNF8 expression promotes the interaction between RARA and RNF8 and induces Lys-48 linkage ubiquitylation and degradation, resulting in attenuated transcriptional activation of .
CONCLUSION
Our results suggest that RNF8 is a key - downstream event. Using the combination of MG132 and ATRA to treat --HL60 cells, a synergistic effect leading to --HL60 cell differentiation was confirmed. Taken together, the targeting of may be an alternative choice for treatment in variant APL with - fusion.
背景
- 是在伴有t(7;17)(q11;q21)的变异型急性早幼粒细胞白血病（APL）患者中新发现的融合基因。该患者的临床表现表明它是一种对全反式维甲酸（ATRA）不敏感的致癌基因，在治疗反应方面与经典的 - 不同。
方法
为揭示 - 融合基因的功能特性和调控机制，我们建立了 - 转染的HL60细胞模型，并通过蛋白质免疫印迹法、MTT法、流式细胞术和瑞氏 - 吉姆萨染色检测其对ATRA的敏感性。采用免疫共沉淀和共聚焦显微镜检测GTF2I - RARA与转录共抑制因子的结合。我们还进行了染色质免疫沉淀测序（ChIP - seq）以寻找潜在的靶基因。采用免疫沉淀、泛素化测定、蛋白质免疫印迹法、荧光素酶测定和实时定量聚合酶链反应（PCR）分析RNF8对RARA的影响。采用流式细胞术和瑞氏 - 吉姆萨染色研究MG132和ATRA对 - 转染的HL60细胞模型的作用。
结果
我们证实了GTF2I - RARA对ATRA耐药。与 - 相比，在ATRA处理下其对组蛋白去乙酰化酶3（HDAC3）具有更高的亲和力。使用ChIP - 测序方法，我们在模型细胞中鉴定出221个 - 结合位点，并发现泛素连接酶8（RNF8）是 - 的一个靶基因。RNF8通过 - 转录本参与APL的疾病进展和治疗耐药。RNF8表达升高促进RARA与RNF8之间的相互作用并诱导赖氨酸48连接的泛素化和降解，导致 - 的转录激活减弱。
结论
我们的结果表明RNF8是 - 的关键下游事件。使用MG132和ATRA联合处理 - HL60细胞，证实了导致 - HL60细胞分化的协同效应。综上所述，靶向 - 可能是治疗伴有 - 融合的变异型APL的一种替代选择。
Zotero 插件