DataSheet_1_CAF-Associated Paracrine Signaling Worsens Outcome and Potentially Contributes to Chemoresistance in Epithelial Ovarian Cancer.docx

BackgroundHigh-grade serous ovarian cancer (HGSOC) is the predominant and deadliest form of ovarian cancer. Some of its histological subtypes can be distinguished by frequent occurrence of cancer-associated myofibroblasts (CAFs) and desmoplastic stroma reaction (DSR). In this study, we want to explore the relationship between therapy outcome and the activity of CAF-associated signaling pathways in a homogeneous HGSOC patient collective. Furthermore, we want to validate these findings in a general Epithelial ovarian cancer (EOC) cohort. MethodsThe investigation cohort consists of 24 HGSOC patients. All of them were treated with platinum-based components and clinical follow-up was available. The validation cohort was comprised of 303 patients. Sequencing data (whole transcriptome) and clinical data were extracted from The Cancer Genome Atlas (TCGA). RNA of HGSOC patients was isolated using a Maxwell RSC instrument and the appropriate RNA isolation kit. For digital expression analysis a custom-designed gene panel was employed. All genes were linked to various DSR- and CAF- associated pathways. Expression analysis was performed on the NanoString nCounter platform. Finally, data were explored using the R programming environment (v. 4.0.3). ResultIn total, 15 CAF-associated genes were associated with patients’ survival. More specifically, 6 genes (MMP13, CGA, EPHA3, PSMD9, PITX2, PHLPP1) were linked to poor therapy outcome. Though a variety of different pathways appeared to be associated with therapy failure, many were related to CAF paracrine signaling, including MAPK, Ras and TGF-β pathways. Similar results were obtained from the validation cohort. DiscussionIn this study, we could successfully link CAF-associated pathways, as shown by increased Ras, MAPK and PI3K-Akt signaling to therapy failure (chemotherapy) in HGSOC and EOCs in general. As platinum-based chemotherapy has been the state-of-the-art therapy to treat HGSOC for decades, it is necessary to unveil the reasons behind resistance developments and poor outcome. In this work, CAF-associated signaling is shown to compromise therapy response. In the validation cohort, CAF-associated signaling is also associated with therapy failure in general EOC, possibly hinting towards a conserved mechanism. Therefore, it may be helpful to stratify HGSOC patients for CAF activity and consider alternative treatment options.研究背景：高级别浆液性卵巢癌（High-grade serous ovarian cancer, HGSOC）是卵巢癌中占比最高且致死性最强的亚型。部分该肿瘤的组织学亚型可通过癌相关成纤维细胞（cancer-associated myofibroblasts, CAFs）的高频出现及促结缔组织增生性间质反应（desmoplastic stroma reaction, DSR）进行区分。本研究旨在探索同质性高级别浆液性卵巢癌患者队列中，治疗结局与癌相关成纤维细胞相关信号通路活性之间的关联，并在整体上皮性卵巢癌（Epithelial ovarian cancer, EOC）队列中验证上述发现。 研究方法：本研究的探索队列共纳入24名高级别浆液性卵巢癌患者，所有患者均接受了以铂类药物为基础的治疗，且均具备完整的临床随访数据。验证队列包含303名患者，其全转录组测序数据与临床资料均从癌症基因组图谱（The Cancer Genome Atlas, TCGA）中获取。高级别浆液性卵巢癌患者的RNA样本通过Maxwell RSC仪器及配套RNA提取试剂盒完成分离。针对数字化基因表达分析，本研究采用了定制化基因面板；所有基因均与多种促结缔组织增生性间质反应及癌相关成纤维细胞相关通路相关联。基因表达分析在NanoString nCounter平台上完成。最终所有数据分析均通过R语言编程环境（版本4.0.3）进行。 研究结果：本研究共鉴定出15个与患者生存相关的癌相关成纤维细胞相关基因。具体而言，6个基因（MMP13、CGA、EPHA3、PSMD9、PITX2、PHLPP1）与不良治疗结局显著相关。尽管多种不同通路均与治疗失败存在关联，但其中多数与癌相关成纤维细胞旁分泌信号通路有关，包括MAPK、Ras及TGF-β通路。验证队列中得到了一致的研究结果。 讨论：本研究成功证实，癌相关成纤维细胞相关信号通路（如Ras、MAPK及PI3K-Akt通路的激活）与高级别浆液性卵巢癌及整体上皮性卵巢癌的化疗治疗失败显著相关。数十年来，铂类化疗始终是高级别浆液性卵巢癌的标准治疗方案，因此阐明其耐药发生与不良预后背后的机制具有重要临床意义。本研究表明，癌相关成纤维细胞相关信号通路会损害肿瘤治疗应答。在验证队列中，癌相关成纤维细胞相关信号通路同样与整体上皮性卵巢癌的治疗失败相关，这提示该机制可能具有保守性。因此，针对高级别浆液性卵巢癌患者的癌相关成纤维细胞活性进行分层，并考虑个体化替代治疗方案，或可具有临床应用价值。