KAI1 overexpression promotes apoptosis and inhibits proliferation, cell cycle, migration, and invasion in nasopharyngeal carcinoma cells.

Objectives: The purpose of this study is to characterize the effect of KAI1 overexpression on the biological behavior of nasopharyngeal carcinoma (NPC) cells. Background: Nasopharyngeal carcinoma is a highly malignant tumor with a high rate of incidence in China. Currently, there are no ideal therapeutic options for patients with NPC, but a targeted therapy would have great potential for treating it. Therefore, there is an urgent need for novel therapeutic targets to provide new options for treating NPC. The KAI1 gene was originally identified as a metastasis suppressor gene for advanced human cancer. In NPC cell lines and tissues, the expression of KAI1 decreased as the metastatic potential of cells increased, but its potential as a therapeutic target has not been elucidated. Methods: Non-transformed nasopharyngeal epithelium cell NP69 and NPC cell line C666-1 were cultured and KAI1 expression in these cells was detected by qRT-PCR and Western blot. After the transfection of KAI1-pCDNA3.1 to NP69 and C666-1, the KAI1 expression in these cells was detected by qRT-PCR and Western blot, the proliferation was performed by MTS, the cell cycle and apoptosis were performed by flow cytometry, the migration and invasion were examined by transwell. Results: Our results showed that KAI1 was significantly upregulated in C666-1 cells compared to that in NP69 cells. In addition, KAI1 overexpression significantly inhibited the proliferation, cell cycle, migration, and invasion, and promoted apoptosis of C666-1 cells, but had no significant effect on NP69 cells. Conclusion: Our findings suggest that KAI1 overexpression promotes apoptosis and inhibits proliferation, cell cycle, migration, and invasion in NPC cells. We hypothesize that KAI1 overexpression could be a potential therapeutic target for NPC. (C) 2016 Elsevier Inc. All rights reserved.