Open Access

ARTICLE

Icotinib Enhanced Radiosensitization of Nasopharyngeal Carcinoma by Inhibiting the Expression of Epidermal Growth Factor Receptor

by Bo Wu^1,#, Huacai Xiong^2,#, Yong Wang¹, Shankun Zhao¹, Hongsheng Lu¹, Wei Hu^3,*

1 Department of Radiotherapy, Taizhou Central Hospital (Taizhou University Hospital), Taizhou, China
2 Department of Radiotherapy, Ningbo Medical Center Lihuili Hospital, Ningbo, China
3 WeiMai Technology Limited Company, Hangzhou, China

* Corresponding Author: Wei Hu. Email:
# These authors contributed equally to this work

Oncologie 2022, 24(3), 553-563. https://doi.org/10.32604/oncologie.2022.023025

Received 06 April 2022; Accepted 21 June 2022; Issue published 19 September 2022

Abstract

Epidermal growth factor receptor (EGFR) is frequently overexpressed in multiple malignancies. Icotinib (IH), a new EGFR tyrosine kinase inhibitor, enhances radiosensitivity in various types of cancer, but its effect on nasopharyngeal carcinoma (NPC) remains unclear. Total 115 NPC tissue sections and 30 nasopharyngitis tissue sections were enrolled. The correlation of EGFR expression and clinicopathologic features of NPC was analyzed. Survival analysis was calculated by using univariate and multivariate regression analysis. A radioresistant NPC cell line, CNE-2R, was established with a gradient irradiation schedule. Cell viability, colony formation and EGFR expression of CNE-2/2R cells were examined. Significant higher expression of EGFR was observed in NPC tissues than chronic nasopharyngitis lesions. EGFR expression was significantly correlated with both tumor stage (P < 0.001) and tumor-node-metastasis stage of NPC (P = 0.006). EGFR expression was an independent prognostic factor of disease-free survival (P = 0.047) and the overall survival of NPC (P = 0.016). Cell viability was higher in CNE-2R than CNE-2 on days 1, 2, 4, and 6 after radiation of 4 Gy. The colony number of CNE-2R was significantly higher than that of CNE-2 (P < 0.05), while IH enhanced the radiosensitizing effect of CNE-2R with lower survival fraction (P < 0.05). EGFR mRNA and protein expression levels were significantly higher in CNE-2R cells compared to CNE-2 cells, but significantly decreased after IH treatment (all P < 0.05). In conclusion, high EGFR expression is a poor prognostic factor for NPC patients. IH enhances the radiosensitivity of CNE-2R cells and reduce EGFR expression.

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Keywords

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