Objective Intrahepatic cholangiocarcinoma (iCCA) is the second most common primary liver cancer with limited therapeutic options. KRAS mutations are among the most abundant genetic alterations in iCCA associated with poor clinical outcome and treatment response. Recent findings indicate that Poly(ADP-ribose)polymerase1 (PARP-1) is implicated in KRAS -driven cancers, but its exact role in cholangiocarcinogenesis remains undefined. Design PARP-1 inhibition was performed in patient-derived and established iCCA cells using RNAi, CRISPR/Cas9 and pharmacological inhibition in KRAS -mutant, non-mutant cells. In addition, Parp-1 knockout mice were combined with iCCA induction by hydrodynamic tail vein injection to evaluate an impact on phenotypic and molecular features of Kras -driven and Kras -wildtype iCCA. Clinical implications were confirmed in authentic human iCCA. Results PARP-1 was significantly enhanced in KRAS -mutant human iCCA. PARP-1-based interventions preferentially impaired cell viability and tumourigenicity in human KRAS -mutant cell lines. Consistently, loss of Parp-1 provoked distinct phenotype in Kras/Tp53- induced versus Akt/Nicd- induced iCCA and abolished Kras -dependent cholangiocarcinogenesis. Transcriptome analyses confirmed preferential impairment of DNA damage response pathways and replicative stress response mediated by CHK1. Consistently, inhibition of CHK1 effectively reversed PARP-1 mediated effects. Finally, Parp-1 depletion induced molecular switch of KRAS -mutant iCCA recapitulating good prognostic human iCCA patients. Conclusion Our findings identify the novel prognostic and therapeutic role of PARP-1 in iCCA patients with activation of oncogenic KRAS signalling. All data relevant to the study are included in the article or uploaded as online supplemental information.

中文翻译：

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PARP-1 选择性损害肝内胆管癌中 KRAS 驱动的表型和分子特征


目的 肝内胆管癌 （iCCA） 是第二常见的原发性肝癌，治疗选择有限。KRAS 突变是 iCCA 中最丰富的基因改变之一，与不良临床结果和治疗反应相关。最近的研究结果表明，Poly（ADP-ribose）polymerase1 （PARP-1） 与 KRAS 驱动的癌症有关，但其在胆管癌发生中的确切作用仍未确定。设计 使用 RNAi 、 CRISPR/Cas9 在患者来源和已建立的 iCCA 细胞中进行 PARP-1 抑制，并在 KRAS 突变、非突变细胞中进行药理学抑制。此外，Parp-1 敲除小鼠与流体动力学尾静脉注射 iCCA 诱导相结合，以评估对 Kras 驱动和 Kras 野生型 iCCA 表型和分子特征的影响。临床意义在真实的人类 iCCA 中得到证实。结果 PARP-1 在 KRAS 突变人 iCCA 中显著增强。基于 PARP-1 的干预措施优先损害人 KRAS 突变细胞系中的细胞活力和致瘤性。始终如一地，Parp-1 的缺失在 Kras/Tp53 诱导的与 Akt/Nicd 诱导的 iCCA 中引起不同的表型，并消除了 Kras 依赖性胆管癌生成。转录组分析证实了 CHK1 介导的 DNA 损伤反应途径和复制应激反应的优先损伤。一致地，抑制 CHK1 有效地逆转了 PARP-1 介导的作用。最后，Parp-1 耗竭诱导 KRAS 突变型 iCCA 的分子转换概括了预后良好的人类 iCCA 患者。结论 我们的研究结果确定了 PARP-1 在致癌 KRAS 信号激活的 iCCA 患者中的新预后和治疗作用。 与研究相关的所有数据都包含在文章中或作为在线补充信息上传。