ESRP1 and breast cancer: Furthermore, Ashok et al. investigated the mechanism that upregulates ESRP1 expression during breast carcinogenesis and found that elevated levels of the transcriptional activator E2F1 and increased CpG hydroxymethylation at the E2F1 binding site in the ESRP1 promoter enhances ESRP1 expression in breast cancer [81].