Efficacy of the hypoxia-activated prodrug evofosfamide (TH-302) in nasopharyngeal carcinoma in vitro and in vivo

Cancer Communications

Lin Liu¹  Xiaobo He²  Yan Huang³  Ying Tian³  Jianhua Zhan³  Yuanyuan Zhao³  Cong Xue³  Li Zhang³ 

[1] Department of Medical Oncology, The Fifth Affiliated Hospital, Sun Yat-Sen University;Department of Radiation Oncology, The Fifth Affiliated Hospital, Sun Yat-Sen University;State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Sun Yat-sen University Cancer Center;

关键词: Nasopharyngeal carcinoma (NPC);    Hypoxia-induced factor-1α (HIF-1α);    Hypoxia-activated prodrug;    Chemotherapy;    Xenograft tumor models;   

DOI  :  10.1186/s40880-018-0285-0

来源: DOAJ

【 摘 要 】

Abstract Background Tumor hypoxia is considered an important factor in metastasis and disease relapse. Evofosfamide is a hypoxia-activated prodrug that selectively targets the hypoxic regions of solid tumors. As hypoxia-inducible factor-1α (HIF-1α) is overexpressed in nasopharyngeal carcinoma (NPC) tissues, we performed the present study to evaluate the efficacy profile of evofosfamide in NPC. Methods We evaluated the efficacy of evofosfamide as a single agent or combined with cisplatin (DDP) in the NPC cell lines CNE-2, HONE-1 and HNE-1, and in nude mouse xenograft tumor models. Results Evofosfamide exhibited hypoxia-selective cytotoxicity in NPC cell lines, with 50% inhibition concentration (IC50) values of 8.33 ± 0.75, 7.62 ± 0.67, and 0.31 ± 0.07 μmol/L under hypoxia in CNE-2, HONE-1 and HNE-1 cells, respectively. The sensitization ranged from ninefold to greater than 300-fold under hypoxia compared with normoxia controls. The combination of evofosfamide with DDP had a synergistic effect on cytotoxicity in the NPC cell lines by combination index values assessment. Cell cycle G2 phase was arrested after treated with 0.05 μmol/L evofosfamide under hypoxia. Histone H2AX phosphorylation (γH2AX) (a marker of DNA damage) expression increased while HIF-1α expression suppressed after evofosfamide treatment under hypoxic conditions. In the HNE-1 NPC xenograft models, evofosfamide exhibited antitumor activity both as a single agent and combined with DDP. Hypoxic regions in xenograft tissue were reduced after both evofosfamide monotherapy and combined therapy with DDP. Conclusions Our results present preclinical evidence for targeting the selective hypoxic portion of NPC by evofosfamide as a single agent and combined with DDP and provide rationale for the potential clinical application of evofosfamide for the treatment of nasopharyngeal carcinoma.

【 授权许可】

Unknown