目的：探讨人结肠癌细胞中高尔基磷蛋白3（GOLPH3）基因表达与Wnt信号通路活性的关系。方法：用RT-PCR方法检测4种人结肠癌细胞（HCT116、HT29、SW480、SW620）中GOLPH3 mRNA的表达，选取GOLPH3高表达的细胞株行GOLPH3基因干扰，用RT-PCR检测干扰效果，然后用TOPFlash报告基因、平板克隆实验、Western blot法分别检测干扰后细胞Wnt信号通路活性、增殖活性以及GOLPH3与β-catenin表达的变化。结果：4种结肠癌细胞中SW620细胞的GOLPH3mRNA相对表达量最高；SW620细胞转染GOLPH3 siRNA后GOLPH3 mRNA的相对表达量明显降低（P<0.001）；与未处理的SW620细胞比较，转染GOLPH3siRNA的SW620细胞Wnt通路转录活性明显降低（0.342 vs. 1.000，P<0.001）、癌细胞集落形成数明显减少（82.333 vs. 207.333，P<0.001）、GOLPH3与β-catenin蛋白表达均明显降低（0.260 vs. 1.00；0.182 vs. 1.00，均P<0.001）。结论：人结肠癌细胞中GOLPH3的高表达可增加Wnt/β-catenin细胞信号通路活性，从而促进细胞增殖。
Relationship between Golgi phosphoprotein 3 expression and Wnt signaling pathway in human colon cancer cells
Objective: To investigate the relationship between the expression of Golgi phosphoprotein 3 (GOLPH3) gene and the activity of Wnt signaling pathway in human colon cancer cells. Methods: The GOLPH3 mRNA expressions in 4 different human colon cancer cell lines (HCT116, HT29, SW480 and SW620) were detected by RT-PCR, after which, the cell line with highest GOLPH3 mRNA expression was selected and then underwent GOLPH3 gene interference, and the RNA interference effect was examined by RT-PCR. In the colon cancer cells after interference, the changes in the activity of Wnt signaling pathway, proliferative ability and protein expressions of GOLPH3 and β-catenin were detected by TOPFlash reporter gene assay, flat plate colony-forming assay and Western blot analysis, respectively. Results: SW620 cells showed the highest relative GOLPH3 mRNA expression among the 4 types of colon cancer cell lines. The relative GOLPH3 mRNA expression was significantly reduced after GOLPH3 siRNA transfection in SW620 cells (P<0.001). In SW620 cells after GOLPH3 siRNA transfection compared with untreated SW620 cells, the transcriptional activity of Wnt signaling pathway was significantly decreased (0.342 vs. 1.000, P<0.001), the number of cancer cell colon formation was significantly reduced (82.333 vs. 207.333, P<0.001), and both GOLPH3 and β-catenin protein expressions were significantly down-regulated (0.260 vs. 1.00; 0.182 vs. 1.00, both P<0.001). Conclusion: In human colon cancer cells, increased GOLPH3 expression may up-regulate the acitivity of Wnt/β-catenin signaling pathway, and thereby promote cell proliferation.