Interestingly, we observed a strong synergy between BI2536 and fasudil in BEAS‐2B‐KRAS cells (CI = 0.57; Fa = 0.88), although the two drugs also synergized (CI = 0.93; Fa = 0.51) in inhibiting BEAS‐2B cell proliferation (Fig 1B; Appendix Fig S1C), suggesting that the combinatorial efficacy of fasudil/BI2536 is not restricted to KRAS‐mutant setting and may come along with toxicity for normal tissue, which is in line with a previous report that fasudil potentiates PLK1 inhibition in KRAS‐mutant cancer (Wang et al, 2016). Here, PLK1 is linked to cancer.