丁酸钠通过调节 ERK 和鞘氨醇激酶 2 诱导人结肠癌细胞凋亡。

Sodium butyrate induces apoptosis of human colon cancer cells by modulating ERK and sphingosine kinase 2.

机构信息

Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou 510515, Guangdong, China; Department of Clinical Laboratory, Affiliated Hospital of Guangdong Medical College, Zhanjiang 524001, Guangdong, China.

Department of Toxicology, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou 510515, Guangdong, China.

出版信息

Biomed Environ Sci. 2014 Mar;27(3):197-203. doi: 10.3967/bes2014.040.

DOI:10.3967/bes2014.040

PMID:24709100

Abstract

OBJECTIVE

To investigate the role of extracellular signal-regulated kinase (ERK) in apoptosis of human colon cancer (HCT116) cells.

METHODS

After the HCT116 cells were pretreated with specific ERK inhibitor (U0126) or specific siRNA and exposed to 10 mmol/L sodium butyrate (NaBT) for 24 h, their apoptosis was detected by flow cytometry, levels of SphK2 and ERK protein were measured by Western blot, and translocation of SphK2 was assayed by immunofluorescence microscopy.

RESULTS

The U0126 and siRNAs specific for SphK2 blocked the export of SphK2 from nuclei to cytoplasm and increased the apoptosis of HCT116 cells following NaBT exposure. Over-expression of PKD decreased NaBT-induced apoptosis of HCT116 cells, which was reversed by U0126. Furthermore, transfection of HCT116 cells with constitutively activated PKD plasmids recovered the U0126-blocked export of SphK2.

CONCLUSION

ERK regulates the export of SphK2 and apoptosis of HCT116 cells by modulating PKD. Modulation of these molecules may help increase the sensitivity of colon cancer cells to the physiologic anti-colon cancer agent, NaBT.

摘要

目的

探讨细胞外信号调节激酶（ERK）在人结肠癌（HCT116）细胞凋亡中的作用。

方法

用特异性 ERK 抑制剂（U0126）或特异性 siRNA 预处理 HCT116 细胞，并用 10mmol/L 丁酸钠（NaBT）处理 24 小时后，通过流式细胞术检测细胞凋亡，Western blot 检测 SphK2 和 ERK 蛋白水平，免疫荧光显微镜检测 SphK2 的易位。

结果

SphK2 的特异性 U0126 和 siRNA 阻断了 SphK2 从细胞核向细胞质的输出，并增加了 NaBT 暴露后 HCT116 细胞的凋亡。过表达 PKD 可降低 HCT116 细胞中 NaBT 诱导的凋亡，而 U0126 可逆转这种作用。此外，用组成性激活的 PKD 质粒转染 HCT116 细胞可恢复 U0126 阻断的 SphK2 输出。