CUX1 and cancer: Very recently, by employing K562 cells, which predominantly express the p200 CUX1, Arthur et al. (100) have demonstrated that p200 CUX1 binds distal cis-regulatory elements associated with gene activation, but the coexistence of p200 CUX1 and its short isoforms in many other cancer cells is still a bottleneck in the process to disclose the exact roles of them in tumor development.