Ito Takahiro, Young Michael J, Li Ruitong, Jain Sidharth, Wernitznig Andreas, Krill-Burger John M, Lemke Christopher T, Monducci Davide, Rodriguez Diego J, Chang Liang, Dutta Sanjukta, Pal Debjani, Paolella Brenton R, Rothberg Michael V, Root David E, Johannessen Cory M, Parida Laxmi, Getz Gad, Vazquez Francisca, Doench John G, Zamanighomi Mahdi, Sellers William R
Broad Institute of Harvard and MIT, Cambridge, MA, USA.
Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.
Nat Genet. 2021 Dec;53(12):1664-1672. doi: 10.1038/s41588-021-00967-z. Epub 2021 Dec 2.
Although single-gene perturbation screens have revealed a number of new targets, vulnerabilities specific to frequently altered drivers have not been uncovered. An important question is whether the compensatory relationship between functionally redundant genes masks potential therapeutic targets in single-gene perturbation studies. To identify digenic dependencies, we developed a CRISPR paralog targeting library to investigate the viability effects of disrupting 3,284 genes, 5,065 paralog pairs and 815 paralog families. We identified that dual inactivation of DUSP4 and DUSP6 selectively impairs growth in NRAS and BRAF mutant cells through the hyperactivation of MAPK signaling. Furthermore, cells resistant to MAPK pathway therapeutics become cross-sensitized to DUSP4 and DUSP6 perturbations such that the mechanisms of resistance to the inhibitors reinforce this mechanism of vulnerability. Together, multigene perturbation technologies unveil previously unrecognized digenic vulnerabilities that may be leveraged as new therapeutic targets in cancer.
尽管单基因扰动筛选已经揭示了一些新的靶点，但尚未发现特定于频繁改变的驱动基因的脆弱性。一个重要的问题是，功能冗余基因之间的补偿关系是否在单基因扰动研究中掩盖了潜在的治疗靶点。为了识别双基因依赖性，我们开发了一个CRISPR旁系同源物靶向文库，以研究破坏3284个基因、5065对旁系同源物和815个旁系同源物家族对细胞活力的影响。我们发现，双特异性磷酸酶4（DUSP4）和双特异性磷酸酶6（DUSP6）的双重失活通过丝裂原活化蛋白激酶（MAPK）信号的过度激活选择性地损害NRAS和BRAF突变细胞的生长。此外，对MAPK途径疗法耐药的细胞对DUSP4和DUSP6扰动变得交叉敏感，因此对抑制剂的耐药机制强化了这种脆弱性机制。总之，多基因扰动技术揭示了以前未被认识的双基因脆弱性，这些脆弱性可能被用作癌症的新治疗靶点。
