顺铂为基础的化疗是治疗生殖细胞肿瘤高效的标准护理四十年，然而，由于缺乏新药物治疗选择除化疗和手术外，经常出现难治病例以残留（耐药）性黄体囊细胞瘤（YST(-R)）成分导致预后不良。本研究的目的是通过解密治疗耐受的分子机制，确定治疗YST的新靶点。此外，我们筛选了一个新型抗体药物偶联物CLDN6（CLDN6-ADC）的细胞毒性疗效，以及针对YST的药理学抑制剂。通过流式细胞术、免疫组织化学染色、固定在福尔马林包埋组织的质谱、磷酸激酶阵列或qRT-PCR测量潜在靶点的蛋白和mRNA水平。使用XTT细胞存活性检测或Annexin V / propidium iodide流式细胞术对GCT和非癌细胞进行细胞存活性、凋亡和细胞周期分析。使用TrueSight Oncology 500检测YST（-R）组织的可药用基因改变。我们证明了CLDN6-ADC治疗增强了CLDN6+ GCT细胞特异性凋亡诱导，与非癌细胞对照相比。根据突变和蛋白质组分析，该研究确定了针对FGF、VGF、PDGF、mTOR、CHEK1、AURKA或PARP信号通路的药物作为治疗YST的有前途的方法。此外，我们确定了与MAPK信号传导、翻译启动和RNA结合有关的因素、细胞外基质相关过程以及氧化应激和免疫反应涉及治疗耐受。总之，本研究提供了一个新的CLDN6-ADC以治疗GCT。此外，本研究提出了新型药理学抑制剂，用于治疗（难治）YST患者，包括FGF、VGF、PDGF、mTOR、CHEK1、AURKA或PARP信号通路阻断剂。最后，本研究阐明了YST治疗耐受的机制。 © 2023年作者（S）。

Being the standard-of-care for four decades, cisplatin-based chemotherapy is highly efficient in treating germ cell tumors (GCT). However, often refractory patients present with a remaining (resistant) yolk-sac tumor (YST(-R)) component, resulting in poor prognosis due to lack of novel treatment options besides chemotherapy and surgery. The aim of this study was to identify novel targets for the treatment of YST by deciphering the molecular mechanisms of therapy resistance. Additionally, we screened the cytotoxic efficacy of a novel antibody-drug-conjugate targeting CLDN6 (CLDN6-ADC), as well as pharmacological inhibitors to target specifically YST.Protein and mRNA levels of putative targets were measured by flow cytometry, immunohistochemical stainings, mass spectrometry of formalin-fixed paraffin-embedded tissues, phospho-kinase arrays, or qRT-PCR. Cell viability, apoptosis and cell cycle assays of GCT and non-cancerous cells were performed using XTT cell viability assays or Annexin V / propidium iodide flow cytometry, respectively. Druggable genomic alterations of YST(-R) tissues were identified by the TrueSight Oncology 500 assay.We demonstrated that treatment with a CLDN6-ADC enhanced apoptosis induction specifically in CLDN6+ GCT cells in comparison with non-cancerous controls. In a cell line-dependent manner, either an accumulation in the G2 / M cell cycle phase or a mitotic catastrophe was observed. Based on mutational and proteome profiling, this study identified drugs targeting the FGF, VGF, PDGF, mTOR, CHEK1, AURKA, or PARP signaling pathways as promising approaches to target YST. Further, we identified factors relevant for MAPK signaling, translational initiation and RNA binding, extracellular matrix-related processes as well as oxidative stress and immune response to be involved in therapy resistance.In summary, this study offers a novel CLDN6-ADC to target GCT. Additionally, this study presents novel pharmacological inhibitors blocking FGF, VGF, PDGF, mTOR, CHEK1, AURKA, or PARP signaling for the treatment of (refractory) YST patients. Finally, this study shed light on the mechanisms of therapy resistance in YST.© 2023. The Author(s).