The results showed that RBM4 knockout by Cas9/sgRNA or knockdown by siRNA also led to the flattened and enlarged morphology of ESCC cells and elevated the percentage of SA-β-gal positive cells (Fig. 1h, j and Supplementary 2c, d), which is in line with the results of RBM4 shRNAs, supporting the conclusion that RBM4 knockdown induced ESCC cellular senescence. This evidence concerns the gene RBM4 and esophageal squamous cell carcinoma.