CDKN2A and urinary bladder cancer: ANRIL (antisense non-coding RNA in the INK4A locus) is a long non-coding RNA (lncRNA) that was originally identified in familial melanoma patients with a large germline deletion in the CDKN2A/B (also known as INK4B-ARF-INK4A) gene cluster and is reported to be deregulated in several malignancies such as gastric, breast, lung and bladder cancer [1,2,3,4,5].