USP33 在结直肠癌组织中的表达及与 Wnt/β-catenin 通路的关系

Expression of USP33 in colorectal cancer tissues and its relationship with Wnt/β-catenin pathway

摘要:

目的 探讨泛素特异性蛋白酶33（USP33）在结直肠癌组织中的表达及其与Wnt/β- 连环蛋 白（β-catenin）通路的关系。方法 选取2015 年1 月—2017 年12 月义乌市中心医院肛肠外科结直肠癌组 织标本及对应的癌旁组织标本90 例。采用免疫组织化学染色测定结直肠癌组织和癌旁组织中USP33 表达； Western blotting 测定结直肠癌组织和癌旁组织中USP33、β-catenin 及C-myc 蛋白水平。结果 结直肠癌 组织中USP33 阳性表达率低于癌旁组织（P <0.05），而β-catenin、C-myc 阳性率高于癌旁组织（P <0.05）。 Dukes 分期C、D 期，有淋巴结转移及有肝转移结直肠癌组织中USP33 阳性率低于A、B 期，无淋巴结转移 及无肝转移者（P <0.05）。不同年龄、性别、肿瘤直径、分化程度及浸润深度结直肠癌组织中USP33 阳性 率比较，差异均无统计学意义（P >0.05）。结直肠癌组织中USP33 蛋白水平低于癌旁组织，而β-catenin、 C-myc 蛋白水平高于癌旁组织（P <0.05）。结直肠癌组织中USP33 蛋白与β-catenin、C-myc 蛋白呈负相 关（P <0.05）。结论 结直肠癌组织中USP33 低表达，USP33 可能通过Wnt/β-catenin 信号通路参与结直肠 癌的发生、发展。

Abstract:

Objective To investigate the expression of ubiquitin-specific protease 33 (USP33) in colorectal cancer tissues and its relationship with Wnt/β-catenin pathway. Methods A total of 90 cases of colorectal cancer tissue specimens and corresponding adjacent tissue specimens in the Department of Anorectal Surgery of Yiwu Central Hospital from January 2015 to December 2017 were selected. Immunohistochemical staining was used to determine the USP33 expression in colorectal cancer tissues and adjacent tissues. The levels of USP33, β-catenin and c-myc protein in colorectal cancer tissues and adjacent tissues were determined by western blot. Results The positive expression rate of USP33 in colorectal cancer tissues was lower than that in adjacent tissues (P < 0.05); the positive rate of β-catenin and C-myc were higher than those of adjacent tissues (P < 0.05); the positive rate of USP33 in patients with Dukes stage C-D, lymph node metastasis and liver metastasis colorectal cancer tissues was lower than that in patients with Dukes A-B, no lymph node metastasis and no liver metastasis (P < 0.05). There were no significant differences in the positive rate of USP33 in colorectal cancer tissues with different age, gender, tumor diameter, degree of differentiation and depth of invasion (P > 0.05). The level of USP33 protein in colorectal cancer tissues was lower than that in adjacent tissues(P < 0.05), and the levels of β-catenin and C-myc protein were higher than those in adjacent tissues (P < 0.05). There was negative correlation between USP33 protein and β-catenin and C-myc protein in colorectal cancer tissues (P < 0.05). Conclusion USP33 is down-regulated in colorectal cancer tissues, and USP33 may participate in the development of colorectal cancer through Wnt/β-catenin signaling pathway.