In vivo Radiosensitization of Human Glioma U87 Cells Induced by Upregulated Expression of DUSP-2 after Treatment with Curcumin

Title:In vivo Radiosensitization of Human Glioma U87 Cells Induced by Upregulated Expression of DUSP-2 after Treatment with Curcumin

Volume: 10 Issue: 2

Author(s): Lei Zhang, Xiaopeng Ding, Jin Huang, Chen Jiang, Boqiang Cao, Yu Qian, Chao Cheng, Minchao Dai, Xiaoyi Guo and Junfei Shao

Affiliation:

Keywords: Apoptosis, curcumin, dual specificity phosphatase 2, glioma, radiosensitization.

Abstract: Within the last decade, extensive research has revealed that curcumin can increase the sensitivity of tumor cells to high-energy X-ray radiation in vitro and dual-specificity phosphatase (DUSPs) are implicated in cancer, obesity, diabetes, inflammation and Alzheimer’s disease. To date, the article about the radiosensitizing effect of curcumin via enhancement of the DUSP-2 pathway was rarely reported. Here, we discuss the radiosensitizing effects of curcumin on suppressing glioma vivo growth. BALB-c nude mice bearing subcutaneous U87 xenografts were treated with curcumin and/or local radiation to assess their vivo response. Tumor growth, real-time PCR, western blotting, immunohistochemical assay and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) were performed to explore the possible mechanism involved. Curcumin in combination with irradiation significantly enhanced the tumor-suppressive effect in vivo compared with local radiotherapy alone. Both mRNA and protein levels of DUSP-2 were significantly upregulated in the curcumin in combination with radiation treatment group. Curcumin pretreatment inhibited radiationinduced extracellular signal-regulated kinases (ERK)/c-Jun N-terminal kinases (JNK) phosphorylation and enhanced radiation-induced tumor cell apoptosis in subcutaneous xenografts. In conclusion, curcumin significantly increased the radiosensitivity of U87 human glioma cells in vivo. The radiosensitizing effect of curcumin was found to be closely related to its pro-apoptosis activity via enhancement of the DUSP-2 pathway.

Cite this article as:

Zhang Lei, Ding Xiaopeng, Huang Jin, Jiang Chen, Cao Boqiang, Qian Yu, Cheng Chao, Dai Minchao, Guo Xiaoyi and Shao Junfei, In vivo Radiosensitization of Human Glioma U87 Cells Induced by Upregulated Expression of DUSP-2 after Treatment with Curcumin, Current Signal Transduction Therapy 2015; 10 (2) . https://dx.doi.org/10.2174/1574362410666150109223303