Role of FH loss in development of HLRCC heriditary kidney cancer

在2018年，（1）我们证明了在NF 2缺乏的乳头状肾癌中靶向Hippo信号通路丢失的可行性。乳头状肾细胞癌（PRCC）是一组组织学和遗传异质性肿瘤，占所有肾脏肿瘤的15-20%，可能需要不同的治疗方法。在22.5%的PRCC中观察到编码Hippo信号通路的关键调节因子的NF 2肿瘤抑制基因的改变。Hippo信号通路通过调节YAP 1的转录活性来控制细胞增殖。NF 2的缺失导致异常的YAP 1激活。Src家族激酶成员Yes也调节YAP 1的转录活性。当我们在三种NF 2缺陷的PRCC细胞系中研究雅普和Yes活性的重要性时，我们发现NF 2缺陷与YAP 1转录靶点表达增加相关，并且基于siRNA的YAP 1和Yes 1敲低下调了该途径并显著降低了细胞活力。达沙替尼和saracatinib对Yes具有强效抑制作用，用任何一种治疗都会导致YAP 1转录靶点下调，细胞活力降低和G 0-G1细胞周期停滞。NF 2缺陷型PRCC的异种移植模型也显示了对达沙替尼的响应的肿瘤生长减少。因此，抑制YAP 1的Yes和随后的转录活性在体外和体内都具有显著的抗肿瘤细胞作用，并可能为NF 2缺陷型PRCC患者提供可行的治疗方法。(2)为了更好地靶向糖酵解癌细胞中的糖酵解，我们参与开发了一种新型的、有效的、细胞活性的基于吡唑的乳酸脱氢酶（LDH）抑制剂。利用定量高通量筛选范式促进命中识别，而基于结构的设计和多参数优化使得能够开发具有有效的生化和基于细胞的LDH酶活性抑制的化合物。先导化合物在MiaPaCa 2胰腺癌和A673尤因肉瘤细胞中表现出LDHA和LDHB的低nM抑制、细胞乳酸产生的亚微摩尔抑制和糖酵解的抑制。此外，使用细胞热位移测定（CETSA）证明了先导化合物对LDHA的稳健靶向接合，并且通过SPR确定药物-靶向停留时间。这些数据的分析表明，药物-靶标停留时间（解离速率）可能是获得该癌症代谢靶标的有效的基于细胞的和持久的体内抑制所考虑的重要属性。事实上，我们的主要LDH抑制剂显示出有效的体内靶向活性。

In 2018, (1) we demonstrated the feasibility of targeting loss of the Hippo signaling pathway in NF2-deficient papillary kidney cancers. Papillary renal cell carcinomas (PRCC) are a histologically and genetically heterogeneous group of tumors that represent 15-20% of all kidney neoplasms and may require diverse therapeutic approaches. Alteration of the NF2 tumor suppressor gene, encoding a key regulator of the Hippo signaling pathway, is observed in 22.5% of PRCC. The Hippo signaling pathway controls cell proliferation by regulating the transcriptional activity of Yes-Associated Protein, YAP1. Loss of NF2 results in aberrant YAP1 activation. The Src family kinase member Yes also regulates YAP1 transcriptional activity. When we investigated the importance of YAP and Yes activity in three NF2-deficient PRCC cell lines, we found that NF2-deficiency correlated with increased expression of YAP1 transcriptional targets, and siRNA-based knockdown of YAP1 and Yes1 downregulated this pathway and dramatically reduced cell viability. Dasatinib and saracatinib have potent inhibitory effects on Yes and treatment with either resulted in downregulation of YAP1 transcription targets, reduced cell viability, and G0-G1 cell cycle arrest. Xenograft models for NF2-deficient PRCC also demonstrated reduced tumor growth in response to dasatinib. Thus, inhibiting Yes and the subsequent transcriptional activity of YAP1 had a substantial anti-tumor cell effect both in vitro and in vivo and may provide a viable therapeutic approach for patients with NF2-deficient PRCC. (2) In order to better target glycolysis in glycolytic cancer cells, we participated in developing a novel, potent, cell-active pyrazole-based inhibitor of lactate dehydrogenase (LDH). Utilization of a quantitative high-throughput screening paradigm facilitated hit identification, while structure-based design and multiparameter optimization enabled development of compounds with potent biochemical and cell-based inhibition of LDH enzymatic activity. Lead compounds exhibit low nM inhibition of both LDHA and LDHB, submicromolar inhibition of celular lactate production, and inhibition of glycolysis in MiaPaCa2 pancreatic cancer and A673 Ewing's sarcoma cells. Moreover, robust target engagement of LDHA by lead compounds was demonstrated using the cellular thermal shift assay (CETSA), and drug-target residence time was determined via SPR. Analysis of these data suggests that drug-target residence time (off-rate) may be an important attribute to consider for obtaining potent cell-based and durable in vivo inhibition of this cancer metabolism target. Indeed, our lead LDH inhibitor demonstrates potent in vivo on-target activity.