PI3K/Akt/FoxO3a信号通路对人鼻咽癌CNE-1、CNE-2细胞增殖及凋亡的影响

FoxO3a drives proliferation and apoptosis through PI3K/Akt signaling pathway in human nasopharyngeal carcinoma CNE-1 and CNE-2 cells

目的探讨FoxO3a对体外培养的人鼻咽癌CNE-1、CNE-2细胞增殖及凋亡的影响是否是通过PI3K/Akt信号通路。方法通过使用LY294002特异性抑制PI3K的活性,免疫印迹法检测FoxO3a及p-Akt蛋白在人鼻咽癌CNE-1、CNE-2细胞的表达,免疫荧光化学检测FoxO3a在鼻咽癌细胞中的亚细胞定位,实时荧光定量PCR检测FoxO3a的mRNA表达水平,MTT法检测鼻咽癌细胞的增殖抑制率,流式细胞术检测鼻咽癌细胞的凋亡率。结果通过使用PI3K特异性抑制剂LY294002,FoxO3a在实验组人鼻咽癌CNE-1、CNE-2细胞中的蛋白和mRNA表达水平均高于对照组(P<0.05),且在CNE-1(P=0.004)、CNE-2(P=0.001)细胞核内的表达量高于对照组,FoxO3a的上调可抑制人鼻咽癌CNE-1、CNE-2细胞的增殖(P<0.05),促进其凋亡(P<0.01)。结论通过抑制PI3K/Akt信号通路的活性可上调人鼻咽癌CNE-1、CNE-2细胞FoxO3a基因的表达,抑制细胞增殖并诱导细胞凋亡,其机制可能与其对FoxO3a的调控有关。

Objective To evaluate the effects of FoxO3a activation on the proliferation and apoptosis through PI3K/Akt signaling pathway in human nasopharyngeal carcinoma （NPC） CNE-1 and CNE-2 cell lines. Methods Western blotting was used to test the protein expression of FoxO3a and p-Akt. Immunofluorescence staining was used to test the subcellular localization of FoxO3a in CNE-1 and CNE-2 cells. Real-time quantitative PCR was used to measure the mRNA level of Foxo3a in the NPC cells. MTT assay and flow cytometry were used to investigate the proliferation and apoptosis in the CNE-1 and CNE-2 cells. Results As compared to the control group, the protein and mRNA levels of FoxO3a were increased using PI3K-specific inhibitor LY294002 in CNE-1 and CNE-2 cells （P〈0.05）, while the nuclear accumulation of FoxO3a was increased significantly in CNE-1 cells （P=0.004） and CNE-2 cells （P=0.001）. The activation of FoxO3a could inhibit cell proliferation （P〈0.05） and promote apoptosis （P〈0.01） of CNE-1 and CNE-2 cells. Conclusion PI3K/Akt signaling pathway inhibition reduces cell proliferation and induces apoptosis of CNE-1 and CNE-2 cells, possibly through the regulation of FoxO3a expression.