SNORD50B and breast cancer: Next, we knocked down SNORD50A and SNORD50B in two p53mt breast cancer cell lines (MDA-MB-231 and HCC1937) and two p53wt breast cancer cell lines (MCF-7 and DU4475) by antisense oligonucleotides (ASOs) targeting SNORD50A and SNORD50B (Supplementary Fig. S2b), and found that SNORD50A and SNORD50B knockdown, either each alone or both, significantly inhibited the proliferation in p53wt breast cancer cells, while promoted the proliferation of p53mt breast cancer cells (Supplementary Fig. S3; Fig. 2a), particularly dual knockdown of SNORD50A and SNORD50B (termed “SNORD50A/B knockdown” hereafter).