The Prognostic Significance of Histone Lysine Demethylase JMJD3/KDM6B in Colorectal Cancer

Jumonji-domain containing 3 (JMJD3) affects transcriptional regulation by demethylating lysine 27 residue of histone 3. We investigated its function and prognostic significance in colorectal cancer (CRC). The influence of JMJD3 on cell proliferation was assessed using quantitative RT-PCR and western blot on the downstream target gene of JMJD3, in knock-down (KD) experiments and clinical samples from 151 CRC patients. Cells with KD JMJD3 significantly increased proliferation through cell cycle progression and apoptosis suppression. Expression of P15INK4B was remarkably decreased in KD JMJD3 cells; and JMJD3 expression strongly correlated with p15INK4B expression in clinical CRC samples (P < 0.001, r = 0.566). Low JMJD3 also was an independent predictor of poor prognosis (P = 0.042) in surgically resected CRC patients. JMJD3 has prognostic significance in CRC and mediates p15INK4B expression. These results imply that elucidation of the JMJD3 role may lead to a new therapeutic approach for CRC patients.