Objective: To investigate the expression of DNMT3b in human bladder cancer tissues and its correlation with postoperative survival of patients with bladder cancer.
Methods: Thirty-eight pairs of surgically resected human bladder cancer tissues and adjacent bladder tissues were detected by immunohistochemistry for DNMT3b expression, and the correlations of DNMT3b expression level were analyzed with the patients'age, gender, pathological grade, tumor size, T stage, lymph node metastasis and TNM stages. Kaplan-Meier survival analysis was performed to assess the effect of DNMT3b expression on survival outcomes of the patients.
Results: High DNMT3b protein expression was detected in 63.16% of the bladder cancer tissues and in 13.16% of the adjacent tissues (P < 0.05). The expression level of DNMT3b was associated with the pathological grade (P=0.002), tumor size (P < 0.001), T stage (P < 0.001), lymphatic metastasis (P=0.039) and TNM stage (P < 0.001), but not with gender or age of the patients. Multivariate logistic regression analysis showed that the protein expression level of DNMT3b was correlated with tumor size (P=0.008) and TNM grades of the tumor (P=0.042). Kaplan-Meier analysis showed that the patients with a high DNMT3b expression had a significantly shorter overall survival than those with a low DNMT3b expression (P=0.021).
Conclusions: DNMT3b overexpression in bladder cancer is closely related to such clinicopathological factors as pathological grade, tumor size, T stage, lymphatic metastasis, and TNM stage and a shorter overall survival of the patients, suggesting the potential value of DNMT3b as a prognostic marker and a new therapeutic target for bladder cancer.
目的: 探讨DNMT3b在人膀胱癌组织的表达和意义及与膀胱癌患者术后生存期的相关性。
方法: 采用免疫组织化学技术（IHC）分别检测DNMT3b基因在38例手术切除人膀胱癌组织和38例相应癌旁组织的蛋白表达水平，分析其表达水平与患者年龄、性别、病理分级、肿瘤大小、T分期，淋巴转移和TNM分期临床病理参数的相关性，探讨DNMT3b对患者预后影响。
结果: 在38例膀胱癌组织中，DNMT3b高表达率为63.16%，而在对应的38例癌旁组织中高表达率为13.16%，两者间具有显著差异（P < 0.05）。DNMT3b在膀胱癌组织中高表达与患者病理分级（P=0.002）、肿瘤大小（P < 0.001）、T分期（P < 0.001）、淋巴转移（P=0.039）和TNM分期（P < 0.001）相关，而与性别、年龄无明确相关性。多因素Logistic回归分析发现，DNMT3b的蛋白表达水平与肿瘤大小（P=0.008）和TNM分级（P=0.042）相关。Kaplan-Meier生存分析显示，DNMT3b高表达组患者的总生存期明显缩短，与低表达组相比具有显著差异性（P=0.021）。
结论: DNMT3b在膀胱癌组织中高表达，与病理分级、肿瘤大小、原发肿瘤范围、淋巴转移和临床分期等临床病理特征及总生存期密切相关，结果提示DNMT3b有望成为判断膀胱癌预后的标志物和肿瘤防治的新的靶点。
Keywords: DNMT3b; bladder cancer; prognosis.