Dysregulated MDR1 by PRDM1/Blimp1 Is Involved in the Doxorubicin Resistance of Non-Germinal Center B-Cell-Like Diffuse Large B-Cell Lymphoma
Dysregulated MDR1 by PRDM1/Blimp1 Is Involved in the Doxorubicin Resistance of Non-Germinal Center B-Cell-Like Diffuse Large B-Cell Lymphoma
复制标题
PRDM1/Blimp1 失调的 MDR1 参与非生发中心 B 细胞样弥漫性大 B 细胞淋巴瘤的阿霉素耐药
DOI：
10.1159/000520070
复制
发表时间：
2021-11-29
期刊：
影响因子：
3.3
通讯作者：
Li, Junmin
中科院分区：
文献类型：
--
作者：
Qing, Kai;Jin, Zhen;Li, Junmin
简介：弥漫性大B细胞淋巴瘤（DLBCL）的化疗耐药机制仍知之甚少，患者预后仍不令人满意。本研究旨在探讨非生发中心B细胞样（non-GCB）DLBCL的耐药机制。研究方法：通过在具有逐渐增加的DOX浓度的培养基中长期孵育细胞来产生多柔比星（DOX）抗性OCI-Ly 3细胞。使用功能基因分组聚合酶链反应（PCR）阵列测定药物代谢相关基因的表达水平。利用生物信息学鉴定了耐药蛋白，随后生成了分子关联网络。使用双荧光素酶报告基因分析系统和染色质免疫沉淀（ChIP）来确定关键基因的关联和机制。采用免疫印迹法和免疫组化法检测耐药基因和靶基因的表达。用斯皮尔曼等级相关系数分析基因表达之间的相关性。结果：利用PCR芯片，在非GCB DLBCL细胞系OCI-Ly 3/DOX-A100中，MDR 1被鉴定为调节DOX耐药的关键基因。双荧光素酶报告基因检测系统表明PRDM 1可抑制MDR 1的转录。ChIP结果显示，PRDM 1能够与MDR 1的启动子区域（-1，132至-996）结合。在OCI-Ly 3/DOX细胞中，随着耐药指数的增加，NF-κB活性和PRDM 1表达降低，而MDR 1表达增加。免疫组化分析显示，在人DLBCL组织样本中，MDR 1的相对表达高于PRDM 1。MDR 1与PRDM 1呈负相关。结论：在非GCB DLBCL细胞中，NF-κB下调PRDM 1，从而通过终止PRDM 1诱导的MDR 1转录抑制来促进MDR 1转录。这种机制可以解释R-CHOP或CHOP联合硼替佐米治疗后非GCB DLBCL疾病复发的原因。我们的研究结果可能为减少DLBCL患者的耐药性提供一种潜在的治疗策略。
Introduction: The chemoresistance mechanism of diffuse large B-cell lymphoma (DLBCL) is still poorly understood, and patient prognosis remains unsatisfactory. This study aimed to investigate drug resistance mechanisms in non-germinal center B-cell-like (non-GCB) DLBCL. Methods: Doxorubicin (DOX)-resistant OCI-Ly3 cells were generated through long-term incubation of cells in a medium with gradually increasing DOX concentrations. The expression levels of genes related to drug metabolism were determined using a functional gene grouping polymerase chain reaction (PCR) array. Drug-resistant proteins were identified using bioinformatics, and molecular association networks were subsequently generated. The association and mechanism of key genes were determined using a dual-luciferase reporter assay System and chromatin immunoprecipitation (ChIP). The expression of drug-resistant genes and target genes was then measured using Western blotting and immunohistochemistry. The correlation between gene expressions was analyzed using Spearman’s rank correlation coefficient. Results: Using the PCR array, MDR1 was identified as the key gene that regulates DOX resistance in OCI-Ly3/DOX-A100, a non-GCB DLBCL cell line. The dual-luciferase reporter assay system demonstrated that MDR1 transcription could be inhibited by PRDM1. ChIP results showed that PRDM1 had the ability to bind to the promoter region (−1,132 to −996) of MDR1. In OCI-Ly3/DOX cells, NF-κB activity and PRDM1 expression decreased with an increase in drug-resistant index, whereas MDR1 expression increased with enhanced drug resistance. Immunohistochemical analysis revealed that relative MDR1 expression was higher than that of PRDM1 in human DLBCL tissue samples. A negative correlation was observed between MDR1 and PRDM1. Conclusion: In non-GCB DLBCL cells, NF-κB downregulates PRDM1 and thereby promotes MDR1 transcription by terminating PRDM1-induced transcriptional inhibition of MDR1. Such a mechanism may explain the reason for disease recurrence in non-GCB DLBCL after R-CHOP or combined CHOP with bortezomib treatment. Our findings may provide a potential therapeutic strategy for reducing drug resistance in patients with DLBCL.