RRM1 and breast cancer: We transfected hnRNPA2B1 full‐length (hnRNPA2B1‐FL) or a deletion mutant lacking the hnRNPA2B1 RRM1 domain (hnRNPA2B1‐del), which displays a binding preference for m6A‐containing RNAs,[28] into PCAT6 knockdown BC cells.