Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
J Pathol. 2022 Aug;257(5):635-649. doi: 10.1002/path.5910. Epub 2022 May 20.
Clear cell carcinoma (CCC) of the cervix (cCCC) is a rare and aggressive type of human papillomavirus (HPV)-negative cervical cancer with limited effective treatment options for recurrent or metastatic disease. Historically, CCCs of the lower genital tract were associated with in utero diethylstilbestrol exposure; however, the genetic landscape of sporadic cCCCs remains unknown. Here we sought to define the molecular underpinning of cCCCs. Using a combination of whole-exome, targeted capture, and RNA-sequencing, we identified pathogenic genetic alterations in the Hippo signaling pathway in 50% (10/20) of cCCCs, including recurrent WWTR1 S89W somatic mutations in 40% (4/10) of the cases harboring mutations in the Hippo pathway. Irrespective of the presence or absence of Hippo pathway genetic alterations, however, all primary cCCCs analyzed in this study (n = 20) harbored features of Hippo pathway deregulation at the transcriptomic and protein levels. In vitro functional analysis revealed that expression of the WWTR1 S89W mutation leads to reduced binding of TAZ to 14-3-3, promoting constitutive nuclear translocation of TAZ and Hippo pathway repression. WWTR1 S89W expression was found to lead to acquisition of oncogenic behavior, including increased proliferation, migration, and colony formation in vitro as well as increased tumorigenesis in vivo, which could be reversed by targeted inhibition of the TAZ/YAP1 complex with verteporfin. Finally, xenografts expressing WWTR1 S89W displayed a shift in tumor phenotype, becoming more infiltrative as well as less differentiated, and were found to be composed of cells with conspicuous cytoplasmic clearing as compared to controls. Our results demonstrate that Hippo pathway alterations are likely drivers of cCCCs and likely contribute to the clear cell phenotype. Therapies targeting this pathway may constitute a new class of treatment for these rare, aggressive tumors. © 2022 The Pathological Society of Great Britain and Ireland.
宫颈透明细胞癌（CCC）是一种罕见且侵袭性强的人乳头瘤病毒（HPV）阴性宫颈癌，对于复发性或转移性疾病的治疗选择有限。历史上，下生殖道的 CCC 与子宫内己烯雌酚暴露有关；然而，散发性 cCCC 的遗传特征尚不清楚。在这里，我们试图确定 cCCC 的分子基础。我们使用全外显子组、靶向捕获和 RNA 测序的组合，在 50%（10/20）的 cCCC 中发现 Hippo 信号通路的致病性遗传改变，包括 Hippo 通路突变的 40%（4/10）病例中 WWTR1 S89W 体细胞突变。然而，无论是否存在 Hippo 通路遗传改变，本研究分析的所有原发性 cCCC（n=20）在转录组和蛋白质水平上均表现出 Hippo 通路失调的特征。体外功能分析显示，WWTR1 S89W 突变的表达导致 TAZ 与 14-3-3 的结合减少，促进 TAZ 的组成型核转位和 Hippo 通路抑制。发现 WWTR1 S89W 表达导致获得致癌行为，包括体外增殖、迁移和集落形成增加以及体内肿瘤形成增加，用维替泊芬靶向抑制 TAZ/YAP1 复合物可逆转这种情况。最后，表达 WWTR1 S89W 的异种移植物表现出肿瘤表型的转变，变得更具浸润性和低分化，并且与对照相比，发现其由具有明显细胞质透明的细胞组成。我们的结果表明，Hippo 通路改变可能是 cCCC 的驱动因素，并可能导致透明细胞表型。靶向该通路的治疗方法可能构成这些罕见侵袭性肿瘤的一类新的治疗方法。
