自噬抑制剂3-甲基腺嘌呤对结直肠腺癌细胞生长与Notch1蛋白表的影响

目的：探讨自噬抑制剂3-甲基腺嘌呤（3-MA）对人大肠癌SW480细胞生长与Notch1蛋白表达的影响。方法：将3-MA（5 mmol/L）作用于SW480细胞24 h后（以培养相同时间无处理的SW480细胞为对照），分别免疫组化和Western blot法检测细胞Notch1蛋白的表达，用CCK-8法和Annexin/PI双染法检测细胞增殖与凋亡。结果：免疫组化与Western blot结果均显示，3-MA作用后，SW480细胞Notch1蛋白的表达明显下调（均P<0.05）；增殖与凋亡检测结果显示，3-MA作用后，SW480细胞增殖率明显降低，而凋亡率明显增加（均P<0.05）。结论： 3-MA能抑制结直肠癌细胞的增殖并促进其凋亡，该作用可能与3-MA抑制Notch1蛋白表达从而改变细胞自噬水平有关。

Effects of autophagy inhibitor 3-methyladenine on growth and Notch1 protein expression in colorectal cancer cells

Objective: To investigate the effects of autophagy inhibitor 3-methyladenine (3-MA) on growth and Notch1 protein expression in human colon cancer SW480 cells. Methods: In SW480 cells after exposure to 3-MA (5 mmol/L) for 24 h (using untreated SW480 cells cultured for the same time period as control), the Notch1 protein expression was determined by immunohistochemical staining and Western blot analysis, and cell proliferation and apoptosis was detected by CCK8 assay and Annexin/PI double staining, respectively. Results: Both results of immunohistochemical staining and Western blot analysis showed that the Notch1 protein expression was significantly down-regulated in SW480 cells after 3-MA treatment (both P<0.05). Results of cell proliferation and apoptosis assay showed that the proliferation was significantly decreased while apoptosis rate was significantly increased in SW480 cells after 3-MA treatment (both P<0.05). Conclusion: 3-MA can suppress the proliferation and promote apoptosis of colorectal cancer cells, which may probably be associated with its inhibition of notch1 protein expression and thereby altering autophagy level of the cells.