Department of Chemistry and Chemical Biology, TU Dortmund University, Dortmund, Germany.
Department of Structural Biochemistry, Max Planck Institute of Molecular Physiology, Dortmund, Germany.
Elife. 2023 Mar 27;12:e82184. doi: 10.7554/eLife.82184.
Mutations within Ras proteins represent major drivers in human cancer. In this study, we report the structure-based design, synthesis, as well as biochemical and cellular evaluation of nucleotide-based covalent inhibitors for KRasG13C, an important oncogenic mutant of Ras that has not been successfully addressed in the past. Mass spectrometry experiments and kinetic studies reveal promising molecular properties of these covalent inhibitors, and X-ray crystallographic analysis has yielded the first reported crystal structures of KRasG13C covalently locked with these GDP analogues. Importantly, KRasG13C covalently modified with these inhibitors can no longer undergo SOS-catalysed nucleotide exchange. As a final proof-of-concept, we show that in contrast to KRasG13C, the covalently locked protein is unable to induce oncogenic signalling in cells, further highlighting the possibility of using nucleotide-based inhibitors with covalent warheads in KRasG13C-driven cancer.
Ras 蛋白内的突变是人类癌症的主要驱动因素。在这项研究中，我们报告了基于结构的设计、合成，以及针对 KRasG13C 的基于核苷酸的共价抑制剂的生化和细胞评估，KRasG13C 是 Ras 的一种重要致癌突变体，过去尚未成功解决。质谱实验和动力学研究揭示了这些共价抑制剂有前景的分子特性，X 射线晶体学分析获得了这些 GDP 类似物与 KRasG13C 共价锁定的首批报告晶体结构。重要的是，用这些抑制剂共价修饰的 KRasG13C 不能再进行 SOS 催化的核苷酸交换。作为最后的概念验证，我们表明与 KRasG13C 相比，共价锁定的蛋白质无法在细胞中诱导致癌信号，这进一步强调了在 KRasG13C 驱动的癌症中使用带有共价弹头的基于核苷酸的抑制剂的可能性。
