RBM15 and breast cancer: While ectopic expression of wild-type (WT) RBM15 increased the stability of SSP mRNAs and the protein expression level of SSP, ΔRRM-RBM15 did not show these effects (Fig. 6f, g) in BC cells, suggesting that RBM15 specifically recognizes SSP mRNAs and influences their m6A levels and stability.