Abstract:  Objective To investigate the expression of kinesin family member 20A (KIF20A) in T1 high-grade (T1HG) bladder cancer tissues and its value in predicting postoperative recurrence. Methods A total of  94 tumor tissues and matched adjacent tissues (≥3 cm from the edge of the tumor) were selected from patients who underwent the first transurethral resection of bladder cancer in the department of urology of our hospital from August 2013 to December 2015, and the postoperative pathological diagnosis was T1HG bladder cancer. The expression of KIF20A protein was detected by immunohistochemistry. The recurrence of the tumor was monitored by cystoscopy, and the value of KIF20A protein expression in predicting postoperative recurrence was analyzed by Cox proportional hazard regression analysis. Results The TCGA database analysis showed that the expression of KIF20A mRNA in bladder cancer tissues was higher than that in normal tissues (P<0.05). Moreover, the disease-free progression rate of patients with bladder cancer in the high expression group of KIF20A was significantly lower than that in the low expression group (P=0.012). The analysis of clinical samples showed that the positive rate of KIF20A protein in T1HG bladder cancer tissues was significantly higher than that in adjacent tissues (12.8% vs 64.9%, P<0.001), and the expression level of KIF20A protein was correlated with age, smoking history, tumor diameter, T1 sub-stage and pathological grade (all P<0.05). Patients with KIF20A protein positive expression had shorter recurrence free survival than those with negative expression(log-rank χ²=16.154, P<0.001). The multivariable Cox proportional hazard regression analysis showed that the positive expression of KIF20A protein was an independent risk factor for postoperative recurrence (OR=3.033, 95%CI:1.451-6.339, P=0.003). Conclusions The KIF20A protein is highly expressed in T1HG bladder cancer tissues, and expected to be an effective biological indicator to predict the postoperative recurrence risk of T1HG bladder cancer.

Key words:  KIF20A, T1HG bladder cancer, Tumor recurrence, Cinicopathologic features