Isoliquiritigenin suppresses the proliferation and induced apoptosis via miR-32/LATS2/Wnt in nasopharyngeal carcinoma

Abstract

Nasopharyngeal Carcinoma is limited by the various severe side-effects and surgery is rarely performed. Iosliquiritigenin has a series of biological activities, such as antiviral, anti-free radical and antitumor. However, the role and underlying mechanism of isoliquiritigenin in nasopharyngeal carcinoma have not been understood yet. Herein, the results revealed that isoliquiritigenin could inhibit cell proliferation in nasopharyngeal carcinoma cell lines, including C666-1 and CNE2, in both Cell Counting Kit-8 (CCK-8) and 5-Ethynyl-2'-deoxyuridine (EdU) assay. In addition, isoliquiritigenin promoted nasopharyngeal carcinoma cell apoptosis, with the up-regulations of Bax, Caspase-3 and Caspase-9 and the down-regulation of Bcl-2. Meanwhile, isoliquiritigenin suppressed nasopharyngeal carcinoma cells migration and invasion with the down-regulation of matrix metalloproteinases (MMP)-2 and MMP-9. Furthermore, the expression of miR-32 was up-regulated in the nasopharyngeal carcinoma tissues, while isoliquiritigenin could significantly down-regulate the expression of miR-32. And over-expression of miR-32 promoted the nasopharyngeal carcinoma cells growth, migration and invasion, and suppressed apoptosis. However, isoliquiritigenin treatment dramatically inhibited the effect of miR-32. Besides, luciferase reporter assay confirmed that large tumor suppressor 2 (LATS2) was a direct target of miR-32. And isoliquiritigenin increased the expression of LATS2, while silencing of LATS2 promoted the nasopharyngeal carcinoma cells growth. Moreover, western blotting discovered that isoliquiritigenin inhibited nasopharyngeal carcinoma cells growth via Wnt signaling pathway. Finally, CNE2 cells transplanted xenografts tumor model in nude mice were performed and it suggested that isoliquiritigenin could inhibit the development of xenografts nude mice, along with the decrease of tumor volume and the expression of miR-32 and LATS2. Overall, isoliquiritigenin was confirmed to be a potent anti-nasopharyngeal carcinoma compound both in vitro and in vivo, and accomplished by regulation of miR-32/LATS2/Wnt.

Keywords: Cell proliferation; Isoliquiritigenin; LATS2; Nasopharyngeal carcinoma; Wnt; microRNA-32.