In contrast, we did not observe a decrease in the viability of A673 (Ewing sarcoma [ES], EWSR1-FLI1+) or RH41 (alveolar rhabdomyosarcoma, PAX3-FOXO1+) cells upon WEE1 KD compared with control (Supplemental Figure 1, A–D). Here, WEE1 is linked to alveolar rhabdomyosarcoma.