C9orf50 and cancer: To further investigate whether C9orf50 knockout affects the growth of other cancer types, we knocked out C9orf50 in Hepa1‐6 (Hepatoma), Pan02 (pancreatic cancer), E0771 (triple‐negative breast cancer), and B16F10 (melanoma), and transplanted these cells into C57BL/6 mice (Figure S3K).