CCDC33激活经典Wnt信号通路促进乳腺癌细胞获得恶性表型

CCDC33 enhances malignant phonotypes of breast cancer cells via activating canonical Wnt signaling pathway

目的探讨CCDC33在乳腺癌中的表达及其与Wnt信号通路的关系。方法免疫组化的方法检测117例乳腺癌和48例癌旁正常乳腺组织中CCDC33中的表达及定位,统计学分析其表达与临床病理因素的关系;Western blot和免疫荧光验证CCDC33在乳腺癌细胞系中的表达水平及亚细胞定位;CCDC33特异性siRNA干扰其在乳腺癌细胞系中的表达,MTT和Transwell实验分别验证CCDC33表达下调对细胞增殖和侵袭能力的调控;Western blot和荧光素酶报告基因检测CCDC33表达下调对Wnt信号转导通路的调控。结果CCDC33在乳腺癌组织细胞浆高表达,其阳性率为64.1%(75/117)明显高于相对应的癌旁组织14.6%(7/48,P<0.001),其高表达与乳腺癌的高TNM分期(P=0.025)、淋巴结转移(P=0.011)及不良预后(P=0.025)明显相关。干扰CCDC33活化的β-catenin及其下游蛋白MMP-7和CyclinD1的表达水平下降,乳腺癌细胞的侵袭和增殖能力也明显下降。结论CCDC33通过激活经典Wnt通路促进乳腺癌的侵袭和增殖能力。

Objective To study the correlation between the expression of CCDC33 and activity of canonical Wnt signaling pathway.Methods The expression and localization of CCDC33 in 117 cases of breast cancer and 48 cases of adjacent normal breast tissue were examined by immunohistochemistry,and the relationship between its expression and clinicopathological factors was analyzed.Western blot and immunofluorescence were performed to verify the expression and subcellular localization of CCDC33 in breast cancer cell lines.CCDC33-specific siRNA was adopted to knockdown CCDC33,and MTT and Transwell were performed to verify the regulation of CCDC33 on cell proliferation and invasion abilities,Western blot and luciferase reporter gene detection were adopted to test the function of CCDC33 in Wnt signaling pathway.Results CCDC33 was highly expressed in the cytoplasm of breast cancer cells(64.1%,75/117),compared to the adjacent normal lung tissues(14.6%,7/48,P<0.001),correlated to high TNM staging(P=0.025),lymph node metastasis(P=0.011)and poor prognosis(P=0.025).knockdown CCDC33 by siRNA significantly down-regulated the expression levels of active-β-catenin and its downstream factors MMP-7 and CyclinD1,decreased the invasion and proliferation abilities of breast cancer cells.Conclusion CCDC33 enhances the invasion and proliferation of breast cancer cells via canonical Wnt signaling pathway.