MIR888: MIR888 is a microRNA located on Xq27.3 and is one of the nine genes mapped in this region. It has been described as a body fluid-specific microRNA, only detected in semen and epididymal tissue [PMC4254261]. In a patient cohort, there was an inverse correlation between the expression of MIR888 and MYCBP [PMC7762311]. The methylation status of the MIR888 promoter was monitored, as gene methylation is dysregulated in bladder cancer [PMC6615232]. E2F1 was found to upregulate miR-888 by accessing the hypomethylated promoter of MIR888, which is normally epigenetically silent [PMC6615232]. The expression of miR-888-5p is normally low and restricted to a few tissues, including testis, cerebellum, heart, and kidney [PMC6615232]. In urothelial bladder cancer (BC), MIR888 is hypomethylated compared to normal tissue [PMC6615232]. Knockdown of MIR888 in BC cells improved DNA double-strand break repair and reduced invasiveness by rescuing APLF levels [PMC6615232]. The expression pattern of MIR888 in normal human tissues is testis-specific [PMC6615232]. Treatment with 5-aza-2-deoxycytidine induced demethylation of the MIR888 CpG island [PMC6615232]. Hypomethylation renders the MIR888 promoter more accessible to its transcription factors [PMC6615232]. In various cancer types, including bladder cancer, upregulation of MIR888 promotes invasive tumor growth [PMC7226545].