Institute of Biomedical Research of Salamanca (IBSAL), Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca) and CIBERONC, Salamanca, Spain.
Department of Pathology and IBSAL, University Hospital of Salamanca, University of Salamanca, 37007, Salamanca, Spain.
J Exp Clin Cancer Res. 2022 Mar 22;41(1):106. doi: 10.1186/s13046-022-02330-4.
Despite the incorporation of novel therapeutics, advanced triple negative breast cancer (TNBC) still represents a relevant clinical problem. Considering this, as well as the clinical efficacy of antibody-drug conjugates (ADCs), we aimed at identifying novel ADC targets that could be used to treat TNBC.
Transcriptomic analyses were performed on TNBC and normal samples from three different studies. Plasma membrane proteins of three cell lines representative of the TNBC subtype were identified by cell surface biotinylation or plasma membrane isolation, followed by analyses of cell surface proteins using the Surfaceome online tool. Immunofluorescence and western studies were used to characterize the action of a CD98hc-directed ADC, which was prepared by in house coupling of emtansine to an antibody that recognized the ectodomain of CD98hc. Xenografted TNBC cells were used to analyze the antitumoral properties of the anti-CD98hc ADC.
Comparative genomic studies between normal breast and TNBC tissues, together with proteomic and bioinformatic analyses resulted in the elaboration of a catalog of potential ADC targets. One of them, the CD98hc transmembrane protein, was validated as an ADC target. An antibody recognizing the ectodomain of CD98hc efficiently internalized and reached the lysosomal compartment. An emtansine-based ADC derived from such antibody was prepared and showed antitumoral properties in TNBC in vitro and in vivo models. Mechanistically, the anti-CD98hc ADC blocked cell cycle progression, that was followed by cell death caused by mitotic catastrophe.
This work describes a list of potential ADC targets in TNBC and validates one of them, the transmembrane protein CD98hc. The studies presented here also demonstrate the robustness of the multiomic approach herewith described to identify novel potential ADC targets.
尽管新型疗法的应用，晚期三阴性乳腺癌（TNBC）仍然是一个重要的临床问题。鉴于这一点，以及抗体药物偶联物（ADC）的临床疗效，我们旨在确定可用于治疗 TNBC 的新型 ADC 靶点。
对来自三个不同研究的 TNBC 和正常样本进行了转录组分析。通过细胞表面生物素化或质膜分离鉴定三种代表 TNBC 亚型的细胞系的质膜蛋白，然后使用 Surfaceome 在线工具分析细胞表面蛋白。免疫荧光和 Western 研究用于表征一种 CD98hc 定向 ADC 的作用，该 ADC 是通过将emtansine 连接到识别 CD98hc 外显子的抗体中来制备的。用异种移植的 TNBC 细胞分析抗 CD98hc ADC 的抗肿瘤特性。
正常乳腺组织和 TNBC 组织之间的比较基因组研究，以及蛋白质组学和生物信息学分析，导致了潜在 ADC 靶点目录的制定。其中之一，CD98hc 跨膜蛋白，被验证为 ADC 靶点。一种识别 CD98hc 外显子的抗体可有效内化并到达溶酶体区室。从该抗体衍生的基于 emtansine 的 ADC 显示出在体外和体内 TNBC 模型中的抗肿瘤特性。从机制上讲，抗 CD98hc ADC 阻断细胞周期进程，随后导致有丝分裂灾难引起的细胞死亡。
这项工作描述了 TNBC 中潜在 ADC 靶点的列表，并验证了其中之一，跨膜蛋白 CD98hc。本文中的研究还证明了本文所述的多组学方法识别新型潜在 ADC 靶点的稳健性。
