The recurrence of diffuse large B-cell lymphoma (DLBCL) has been observed in 40% of cases. The standard of care for refractory/relapsed DLBCL (RR-DLBCL) is platinum-based treatment prior to autologous stem cell transplantation; however, the prognosis for RR-DLBCL patients remains poor. Thus, to identify genes affecting the cisplatin response in DLBCL, cisplatin-based whole-genome CRISPR-Cas9 knockout screens were performed in this study. We discovered DNA damage response (DDR) pathways as enriched among identified sensitizing CRISPR-mediated gene knockouts. In line, the knockout of the nucleotide excision repair genesXPAandERCC6sensitized DLBCL cells to platinum drugs irrespective of proliferation rate, thus documenting DDR as essential for cisplatin sensitivity in DLBCL. Functional analysis revealed that the loss ofXPAandERCC6increased DNA damage levels and altered cell cycle distribution. Interestingly, we also identifiedBTK,which is involved in B-cell receptor signaling, to affect cisplatin response. The knockout ofBTKincreased cisplatin sensitivity in DLBCL cells, and combinatory drug screens revealed a synergistic effect of the BTK inhibitor, ibrutinib, with platinum drugs at low concentrations. Applying local and external DLBCL cohorts, we addressed the clinical relevance of the genes identified in the CRISPR screens.BTKwas among the most frequently mutated genes with a frequency of 3–5%, andXPAandERCC6were also mutated, albeit at lower frequencies. Furthermore, 27–54% of diagnostic DLBCL samples had mutations in pathways that can sensitize cells to cisplatin. In conclusion, this study shows thatXPAandERCC6, in addition toBTK, are essential for the response to platinum-based drugs in DLBCL.
弥漫性大B细胞淋巴瘤（DLBCL）的复发率约为40%。对于难治性/复发性DLBCL（RR-DLBCL），标准治疗方案是在自体干细胞移植前进行铂类药物治疗，但RR-DLBCL患者的预后仍然较差。因此，为识别影响DLBCL中顺铂反应的基因，本研究进行了基于顺铂的全基因组CRISPR-Cas9敲除筛选。我们发现，在已鉴定的增敏性CRISPR介导的基因敲除中，DNA损伤应答（DDR）通路显著富集。相应地，核苷酸切除修复基因XPA和ERCC6的敲除使DLBCL细胞对铂类药物敏感，且与增殖速率无关，从而证实DDR对DLBCL的顺铂敏感性至关重要。功能分析显示，XPA和ERCC6的缺失增加了DNA损伤水平并改变了细胞周期分布。有趣的是，我们还发现参与B细胞受体信号转导的BTK基因影响顺铂反应。BTK的敲除增加了DLBCL细胞对顺铂的敏感性，联合药物筛选显示BTK抑制剂伊布替尼在低浓度下与铂类药物具有协同效应。通过分析本地及外部DLBCL队列，我们评估了CRISPR筛选中鉴定基因的临床相关性。BTK是最常见的突变基因之一，突变频率为3-5%，XPA和ERCC6也存在突变，但频率较低。此外，27-54%的诊断性DLBCL样本在可增强细胞对顺铂敏感性的通路中存在突变。总之，本研究表明，除BTK外，XPA和ERCC6对DLBCL中铂类药物的反应也至关重要。
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