Vikramdeo Kunwar Somesh, Miree Orlandric, Anand Shashi, Sharma Amod, Srivastava Sanjeev Kumar, Singh Seema, Rocconi Rodney P, Singh Ajay Pratap
Cancer Center and Research Institute, University of Mississippi Medical Center, Jackson, MS, USA.
Department of Cell and Molecular Biology, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS, 39216, USA.
J Ovarian Res. 2025 Aug 11;18(1):179. doi: 10.1186/s13048-025-01761-9.
Ovarian cancer (OC) remains the most lethal gynecologic malignancy in the United States due to its late diagnosis, aggressive nature, and poor responsiveness to existing therapies. Dissecting the molecular mechanisms and identifying molecular drivers of aggressiveness and therapy resistance is critical for devising new therapies and improving patient outcomes.
MYB expression was evaluated in a panel of OC cell lines by immunoblotting. Gain and loss of function studies were performed by developing stable control and forced-MYB-expressing and -silenced cell lines, respectively. Functional assays included growth kinetics, clonogenicity, cell cycle, live-dead cell measurements, and annexin-V staining, followed by flow cytometry, migration and invasion assays, and MTT assays following drug treatment. Gene expression profiling was done using the nanoString PanCancer Progression panel. Chromatin immunoprecipitation (ChIP) was performed to confirm MYB binding to the responsive gene promoter, followed by siRNA-mediated silencing to establish the intermediary role in potentiating the downstream effects.
Low to high MYB expression was reported in all OC cell lines, with negligible expression reported in normal ovarian surface epithelial cells. MYB expression was significantly higher in aggressive (SKOV3-ip) and chemoresistant (A2780-CP) OC cell lines compared to the parental (SKOV3 and A2780) cells. Functional assays in MYB-overexpressing and -silenced OC cell lines demonstrated a role of MYB overexpression in increased cell proliferation, survival, migration, invasion, EMT, and chemoresistance. nanoString analysis and comparison of transcriptomic data of MYB-silenced SKOV3-ip and MYB-overexpressing SKOV3 cells with their respective control cells identified MYB-dependent genes. Interestingly, these target genes showed a limited overlap between cell lines, suggesting a cell-specific MYB-regulated gene regulation. AKT3 was consistently identified as a common MYB-regulated gene in multiple OC cell lines and confirmed as a direct transcriptional MYB target through confirmation of MYB binding to its promoter. Pathway analysis using the MYB-regulated transcriptomic data also identified PI3K/Akt signaling to be activated in MYB-overexpressing cells. siRNA-mediated silencing of AKT3 confirmed its role in potentiating the oncogenic actions of MYB in OC cells.
MYB/AKT3 axis drives ovarian cancer growth, aggressiveness, and chemoresistance, highlighting its potential as a therapeutic target in ovarian cancer.
卵巢癌（OC）在美国仍然是最致命的妇科恶性肿瘤，原因在于其诊断较晚、侵袭性强以及对现有疗法反应不佳。剖析分子机制并确定侵袭性和治疗耐药性的分子驱动因素对于设计新疗法和改善患者预后至关重要。
通过免疫印迹法在一组OC细胞系中评估MYB表达。分别构建稳定的对照细胞系以及强制表达MYB和沉默MYB的细胞系，进行功能获得和功能缺失研究。功能检测包括生长动力学、克隆形成能力、细胞周期、活死细胞检测、膜联蛋白-V染色，随后进行流式细胞术、迁移和侵袭检测以及药物处理后的MTT检测。使用nanoString泛癌进展检测板进行基因表达谱分析。进行染色质免疫沉淀（ChIP）以确认MYB与反应性基因启动子的结合，随后通过小干扰RNA（siRNA）介导的沉默来确定其在增强下游效应中的中介作用。
在所有OC细胞系中均报告有低至高的MYB表达，而在正常卵巢表面上皮细胞中报告的表达可忽略不计。与亲代（SKOV3和A2780）细胞相比，侵袭性（SKOV3-ip）和化疗耐药性（A2780-CP）OC细胞系中的MYB表达显著更高。在过表达MYB和沉默MYB的OC细胞系中进行的功能检测表明，MYB过表达在细胞增殖增加、存活、迁移、侵袭、上皮-间质转化（EMT）和化疗耐药性中发挥作用。对沉默MYB的SKOV3-ip和过表达MYB的SKOV3细胞及其各自对照细胞的转录组数据进行nanoString分析和比较，确定了MYB依赖性基因。有趣的是，这些靶基因在细胞系之间显示出有限的重叠，表明存在细胞特异性的MYB调节的基因调控。AKT3在多个OC细胞系中始终被确定为常见的MYB调节基因，并通过确认MYB与其启动子的结合而被确认为直接的转录MYB靶标。使用MYB调节的转录组数据进行的通路分析还确定PI3K/Akt信号通路在过表达MYB的细胞中被激活。siRNA介导的AKT3沉默证实了其在增强MYB在OC细胞中的致癌作用中的作用。
MYB/AKT3轴驱动卵巢癌的生长、侵袭性和化疗耐药性，突出了其作为卵巢癌治疗靶点的潜力。
