DUSP6 and neoplasm: The relationship between the total tumour concentration of RMC-7977 and inhibition of the RAS pathway transcriptional target DUSP6 in tumour lysates yielded an EC50 of 130 nM (Extended Data Fig. 8a), consistent with the measured KRAS(G12V) Kd2 of 85 nM (Extended Data Table 1), and with the model for tri-complex RAS inhibition discussed above.